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The Promises and Pitfalls of an All-Electric Yacht

• By Tim Murphy
• Updated: November 8, 2021

This past October, I saw one of the most interesting exhibits in more than 500 new cruising sailboats I’ve reviewed over two decades. It was the Arcona 435Z, built in Sweden and introduced by Graham Balch of Green Yachts in San Francisco. Balch describes his business as “a new brokerage dedicated to the electric revolution on the water,” and it was the “Z” in the boat’s name, which stands for “zero emissions,” that made this boat so interesting. This was the first electric propulsion system—not hybrid but all-electric —I’d ever seen on a cruising sailboat.

Electric propulsion isn’t new. Since 1879, electric motors have propelled boats; a fleet of some four-dozen electric launches transported visitors around the 1893 Colombian Exposition in Chicago. But cruising sailboats are not launches, and the open sea is not a protected canal. When we’re using cruising boats as they’re meant to be used, they seldom end their day plugged into a shore-power outlet. Cruising boats comprise many devices —stove, refrigerator, freezer, windlass, winches, autopilot, radar, lights—whose power typically comes from a tank of fossil fuel. And today’s cruising sailors are accustomed to using diesel auxiliary power to motor through lulls or punch into headwinds and seas.

Starting about 15 years ago, we saw a wave of diesel-electric and hybrid propulsion systems on production and custom cruising boats ( see “Perpetuated Motion,” CW , March 2005 ). Both of those systems ultimately start with an onboard internal-combustion engine. A diesel-electric propulsion system relies on a running genset to directly power the electric motor that turns the propeller. A hybrid system relies on batteries to power the electric motor, plus an internal-combustion genset to recharge the batteries. One of the promises of a hybrid system is the ability to regenerate electrical power. Regeneration means using boatspeed under sail to turn the propeller, whose spinning shaft sends electrons from the electric motor back through an electronic controller to recharge the batteries. In such a system, the boat’s propeller is both an electrical load (when running under power) and a charging source (when sailing in regeneration mode).

The Arcona 435Z was different from both of these systems: It incorporates no onboard fossil-fuel engine at all. Instead, it has a bank of lithium batteries, several solar panels, and a proprietary propulsion leg that looks like a saildrive. “This boat,” Balch said, “has the very first production unit in the world of Oceanvolt’s newest electric propulsion system, called the ServoProp.”

For our sea trial, Balch was joined by Derek Rupe, CEO of Oceanvolt USA. “If you can sail the boat and you have some solar, you can go anywhere in the world, and you can make all your power underway while you go,” Rupe said. When we spoke in October 2020, he touted three high-profile sailors who were using the Oceanvolt electric propulsion system: Alex Thomson, for his Hugo Boss Open 60 Vendée Globe program; Jimmy Cornell, for his Elcano 500 expedition; and Riley Whitelum and Elayna Carausu, who had been teasing their new boat for months on their popular Sailing La Vagabonde YouTube channel.

The efficiency of Oceanvolt’s ServoProp and the regeneration from it is the promised game-changer in each of these boats. The ServoProp is a leg with a ­feathering propeller that can be set for optimal pitch in three modes: forward, reverse and regeneration.

“You don’t need fuel,” Rupe said. “You don’t need to dock; you can go anywhere you want to go and always have the power for living and propulsion.”

That’s the promise. But are there also pitfalls?

Innovation and Risk

Marine electric propulsion is an emerging technology. Compared with the mature and settled technology of diesel engines and lead-acid batteries, electric-propulsion systems—with their electronic controllers and lithium batteries—are in a stage of development best described as adolescent. Every sailor has his or her own tolerance for technical innovation. For the promise of fewer ­seconds per mile, grand-prix-racing sailors willingly trade a high risk of expensive damage to the sails, rig or the boat’s structure itself; cruising sailors, by contrast, tend to favor yearslong reliability in their equipment as they seek miles per day.

Folks who identify as early adopters take special joy in the first-wave discoveries of a new technology; if they’re clear-eyed about supporting an ongoing experiment, they see themselves as partners with the developers, accepting failures as opportunities for learning. Sailors motivated primarily by changing the trajectory of climate change might be especially willing to modify their behavior to limit their own output of greenhouse gases. Investing in any emerging technology asks you to start with a clear assessment of your own risk tolerance. We’ll return to this theme with one or two real-life examples.

The American Boat and Yacht Council, founded in 1954, sets recommended standards for systems installed on recreational boats. For decades, ABYC has published standards related to installations of diesel and gasoline engines, as well as electrical systems based around lead-acid batteries. By contrast, it was only three years ago that ABYC came out with its first electric-propulsion standard (revised July 2021). And only last year it published its first technical-information report on lithium batteries (a technical-information report is an early step toward a future standard). The takeaway is that if you need help servicing your diesel engine or electrical system built around lead-acid batteries, you can pull into any reasonable-size port and find competent technicians to help you. With electric propulsion and lithium batteries, that pool of skilled talent is significantly scarcer.

To say that a technology is mature simply means that we’ve learned to live with it, warts and all, but that it holds few remaining surprises. Certainly, diesel-propulsion and lead-acid-battery technologies each leave plenty of room for improvement. When a charge of fuel ignites in the combustion ­chamber of a diesel engine, some three-quarters of the energy is lost in heat and the mechanical inefficiencies of converting reciprocating motion to rotation. Lead-acid batteries become damaged if we routinely discharge more than half of their capacity. During charging, they’re slow to take the electrons we could deliver.

Lithium batteries are comparatively full of promise. Their power density is far greater than that of lead-acid batteries, meaning they’re much lighter for a given capacity. They’re capable of being deeply discharged, which means you can use far more of the bank’s capacity, not merely the first half. And they accept a charge much more quickly; compare that to several hours a day running an engine to keep the beers iced down.

But the pitfalls? Let’s start with ABYC TE-13, Lithium Ion Batteries. Some of its language is bracing. “Lithium ion batteries are unlike lead-acid batteries in two important respects,” the report says. “1) The electrolyte within most lithium ion batteries is flammable. 2) Under certain fault conditions, lithium ion batteries can enter a condition known as thermal runaway, which results in rapid internal heating. Once initiated, it is a self-perpetuating and exothermic reaction that can be difficult to halt.”

Thermal runaway? Difficult to halt? Self-perpetuating?

“Typically, the best approach is to remove heat as fast as possible, which is most effectively done by flooding the battery with water,” TE-13 continues, “although this may have serious consequences for the boat’s electrical systems, machinery, buoyancy, etc.”

If you were following the news in January 2013, you might remember the ­story of Japan Airlines Flight 008. Shortly after landing at Boston’s Logan Airport, a mechanic opened the aft ­electronic equipment bay of the Boeing 787-8 to find smoke and flames billowing from the auxiliary-power unit. The fire extinguisher he used didn’t put out the flames. Eventually Boston firefighters put out the fire with Halotron, but when removing the still-hissing batteries from the plane, one of the ­firefighters was burned through his ­professional protective gear.

Samsung Galaxy cellphones, MacBook Pro laptops, powered skateboards—in the past decade, these and other devices have been recalled after their lithium batteries burned up. In that period, several high-end custom boats were declared a total loss following failures from lithium batteries. In March 2021, a 78-foot Norwegian hybrid-powered tour boat, built in 2019 with a 790 kW capacity battery bank, experienced thermal runaway that kept firefighters on watch for several days after the crew safely abandoned the ship.

Yes, experts are learning a lot about how to mitigate the risks around lithium batteries. But we’re still on the learning curve.

ABYC’s TE-13 “System Design” section starts, “All lithium-ion battery ­systems should have a battery ­management system (BMS) installed to prevent damage to the battery and provide for battery shutoff if potentially dangerous conditions exist.” It defines a bank’s “safe operating envelope” according to such parameters as high- and low-voltage limits, charging and discharging temperature limits, and charging and ­discharging current limits.

Graham Balch takes these safety recommendations a step further: “To our knowledge, the BMS has to monitor at the cell level. With most batteries, the BMS monitors at the module level.” The difference? “Let’s say you have 24 cells inside the battery module, and three of them stop working. Well, the other 21 have to work harder to compensate for those three. And that’s where thermal events occur.”

Balch followed the story of the Norwegian tour boat this past spring. He believes that the battery installation in that case didn’t meet waterproofing standards: “The hypothesis is that due to water intrusion, there was reverse polarity in one or more of the cells, which is worse than cells simply not working. It means that they’re actively working against the other cells. But if the BMS is monitoring only at the module level, you wouldn’t know it.”

On the Green Yachts website, Graham lists five battery manufacturers whose BMS regimes monitor at the cell level. “If I were sailing on an electric boat, whether it be commercial or recreational, I would feel comfortable with having batteries from these five companies and no other,” he said.

The broader takeaway for today’s sailors is that lithium batteries bring their own sets of problems and solutions, which are different from those of conventional propulsion and power-supply technologies. A reasonably skilled sailor could be expected to change fuel filters or bleed a diesel engine if it shuts down in rough conditions. With lithium-ion batteries aboard, an operator needs to understand the causes and remedies of thermal runaway, and be ready to respond if the BMS shuts down the boat’s power.

Real-World Electric Cruising Boats

When we met Oceanvolt’s Derek Rupe a year ago, he and his wife had taken their all-electric boat to the Bahamas and back the previous season. Before that, he’d been installing electric-propulsion packages for six years on new Alerion 41s and other refit projects. “My real passion is on the technical side of things—installations, really getting that right. That’s half the picture. The technology is there, but it needs to be installed correctly.”

When talking to Rupe, I immediately encountered my first learning curve. I posed questions about the Oceanvolt system in amps and amp-hours; he responded in watts and kilowatt-hours. This was yet another example of the different mindset sailors of electric boats need to hold. Why? Because most cruising boats have just one or two electrical systems: DC and AC. The AC system might operate at 110 or 220 volts; the DC side might operate at 12 or 24 volts. On your own boat, that voltage is a given. From there we tend to think in terms of amps needed to power a load, and amp-hours of capacity in our battery banks. Going back to basics, the power formula tells us that power (watts) equals electrical potential (volts) times current (amps). If your boat’s electrical system is 12 volts and you know that your windlass is rated at 400 watts, it follows that the windlass is rated to draw 33 amps.

But an all-electric boat might comprise several systems at different voltages. A single battery bank might supply cabin lights at 12 volts DC; winches and windlasses at 24 volts DC; the propulsion motor at 48 volts DC; and an induction stove, microwave and television at 110 volts AC. A DC-to-DC power converter steps the voltage up or down, and an inverter changes DC to AC. Instead of translating through all those systems, the Oceanvolt monitor (and Derek Rupe) simply reports in watts coming in or going out of the bank.

“We keep all our thoughts in watts,” Rupe said. “Watts count in the AC induction. They count in the DC-to-DC converter. They count the solar in. They count the hydrogeneration in. And the ­power-management systems tracks it that way for shore-power in.

“On a boat like this, maybe I have 500 watts coming in the solar panels,” he continued. “So then I can think: ‘Well, my fridge is using 90 watts. My boat has an electric stove. When I cook a big meal, I can see that for every hour we cook, we lose about 10 to 12 minutes of our cruising range.’”

During his Bahamas cruising season, Rupe observed that on days that they were sailing, the combination of solar panels and hydroregeneration supplied all the power he and his wife needed. “When we weren’t sailing,” he said, “we found that we were losing 8 percent each day, in the difference from what the sun gave us to what we were using for the fridge, lights, charging our laptops, and all that stuff.”

Rupe’s solution? “Twice in Eleuthera and once outside Major’s, we went out and sailed laps for a couple of hours because the batteries were below 30 percent of capacity. It was good sailing, and the wind was coming over the shore, so we didn’t have any sea state. We did a couple of hot laps on nice beam reaches, and generated about 700 watts an hour.”

Of the three sailors Rupe touted in October 2020—Alex Thomson, Jimmy Cornell and the Sailing La Vagabonde couple—only Cornell can report back on his all-electric experiences with Oceanvolt. Alex Thomson ended his circumnavigation abruptly last November, just 20 days after the Vendée Globe start, when Hugo Boss collided with an object in the South Atlantic. And at press time in early fall 2021, Riley and Elayna had just recently announced the build of their new Rapido trimaran; keep an eye on their YouTube channel for more about their experiences with the Oceanvolt propulsion system.

As for Cornell—circumnavigator, World Cruising Routes author, creator of the transoceanic rally, and veteran of some 200,000 ocean miles—he suspended his planned Elcano 500 round-the-world expedition solely because of the Oceanvolt system in his new Outremer catamaran. His Aventura Zero Logs on the Cornell Sailing website, particularly the Electric Shock article posted on December 2, 2020, are essential reading for any sailor interested in sailing an electric boat. “Sailing around the world on an electric boat with zero emissions along the route of the first circumnavigation was such a tempting opportunity to do something meaningful and in tune with our concern for protecting the environment that my family agreed I should do it,” Cornell wrote. “What this passage has shown was that in spite of all our efforts to save energy, we were unable to regenerate sufficient electricity to cover consumption and top up the batteries.”

Cornell’s experience in that article is raw, and his tone in that moment bitterly disappointed. We recommend it as essential reading—not as a final rejection of the electric-boat concept or of Oceanvolt’s system, or even as an endorsement of Cornell’s own decision that the system didn’t work. I suspect that I may have arrived at the same conclusion. Yet given the same boat in the same conditions, one imagines that a new breed of sailor—a Graham Balch or a Derek Rupe—may have responded differently to the constraints imposed by an all-electric boat, as nearly every cruising sailor today habitually responds to the inconvenient constraints of diesel engines and lead-acid batteries.

“If you bring electric winches, electric heads and an induction stove, and then sail into a high-pressure system, you’ll set yourself up for failure,” Balch said. “You have to balance your power inputs and your power outputs.

“Sailing an electric boat is a return to the tradition of sailing that the crutch of a diesel engine has gotten us away from,” he added. “Magellan’s fleet got all the way around the world, and they didn’t have a diesel engine.”

Tim Murphy is a Cruising World editor-at-large and ­longtime Boat of the Year judge.

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Frequently Asked Questions

• Quiet and vibration-free operation
• No exhaust fumes or fuel smell
• Seamless shifting between forwards and reverse
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While sailing, our motor systems can harness wind power to recharge your batteries. Our display enables you to optimize energy capture by adjusting the braking level in real-time to match the sailing conditions. The amount of regeneration depends on various factors, with the propeller size being the primary determinant.

The motor size required for your boat depends on several factors, primarily the vessel’s size, weight, and operating conditions (such as currents, open sea, tides). User preference is also a consideration. As a rule of thumb, for displacement vessels, 1kW of electric power can replace approximately 3HP of diesel power. This may seem contradictory, but diesel motors are typically oversized to make up for their inefficiency and limited power delivery. 

To assist you in motor sizing, we have developed an electric power calculator to simulate your vessel’s performance. Additionally, we provide a complimentary electrification report outlining the performance capabilities for your specific boat.

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Electric motors possess comparable power to diesel motors, while offering additional features that make them highly suitable for marine propulsion. They exhibit greater efficiency, typically 2 to 3 times more efficient than diesel motors, enabling an electric motor with one-third the size and weight to match the power output of a diesel motor. Moreover, electric motors can deliver torque across a broader range of speeds and provide full torque from 0 RPM.

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Home » Blog » Gear » Buyers guide to electric boat motors (2023)

Buyers guide to electric boat motors (2023)

By Author Fiona McGlynn

Posted on Last updated: August 3, 2023

Considering making the switch to an electric boat motor? With electric vehicles now commonplace on the roads, it’s no wonder so many boaters are curious about electric boats.

While electric boat motors have been around for a while, in the last several years the technology has taken huge leaps, resulting in more powerful motors, longer-lasting batteries, and ultimately more options for recreational boat owners.

Today, many types of boats can be outfitted with an electric propulsion system including pontoon boats, sailboats, jon boats, powerboats, fishing boats, yachts, and trawlers . If your boat’s combustion engine is in the range of 1 to 135 hp (.75 to 100 kW), you should be able to find an electric substitute.

While electric boating hasn’t gone mainstream—it’s estimated that close to 2% of recreational boats are electric—it’s still a great time to be thinking about making the switch, particularly if you own a tender, sailboat, or boat on a green lake where combustion engines are prohibited.

Table of contents

• 1.1 Benefits
• 1.2 Drawbacks
• 2.1.1 Key features of electric outboard boat motors
• 2.1.2 Electric outboard manufacturers
• 2.2.1 DIY electric inboard boat motor conversion
• 2.2.2 Key features of electric inboard boat motors
• 2.2.3 Electric inboard manufacturers
• 2.3.1 Serial vs. parallel hybrids
• 2.3.2 Key features of marine hybrids
• 2.3.3 Marine hybrid manufacturers
• 2.4.1 Electric pod and sail drive manufacturers
• 3 Batteries
• 4 Ready to catch the electric boating wave?

Benefits and drawbacks of electric boat motors

Electric marine motors offer several advantages over internal combustion engines:

• They’re completely silent .
• No noxious fumes or smelly exhaust gases to deal with.
• Instant torque.  Electric propulsion provides instant torque, giving you better maneuverability and more consistent speeds in choppy conditions.
• Lightweight.  An electric setup (including motor, batteries, and generator) typically weighs less than its diesel counterpart.
• No fuel cost.  Charging an electric boat may cost a couple of dollars per charge.
• Easy to maintain.  Imagine the maintenance on an outboard with no gas, spark plugs, or oil! Electric motors are simple, more reliable, and virtually maintenance-free.
• Renewable power.  Once you’ve gone electric you can get power from renewable sources like wind generators and solar panels.
• Better for the planet.  Electric marine motors don’t produce water pollution or produce harmful emissions like carbon dioxide (CO2), nitrogen oxides (NOx), and hydrocarbon (HC).

• Range.  The greatest drawback of electric boats is their limited range, which is often measured in the 10s of miles. Range is limited because batteries don’t have the same energy density as fuel — they can’t provide the same energy, pound-for-pound as a tank of gas. A good battery monitoring system, one that displays the remaining range in real-time, can help boaters manage energy consumption and ease range anxiety. For those who want to go farther afield, hybrid propulsion may be a better option.
• Upfront cost.  This new technology isn’t cheap. For example, a small electric outboard boat motor may sell for two-and-a-half times the cost of a gas outboard. However, prices are expected to come down as the industry reaches scale.

Types of electric boat motors

Electric outboard boat motors.

Some of the first electric outboards to hit the recreational boating market were smaller electric motors, typically used as trolling motors on fishing boats.

Today,  it’s possible to buy far more powerful electric outboard motors in the 1 to 80 hp (.75 to 60 kW) range , with ever more powerful versions hitting the market each year. In 2022, Norwegian start-up, Evoy launched the world’s most powerful outboard to date, the 225kW Storm, a 300-hp beast of an electric outboard! 

The range on electric outboard boat motors varies dramatically depending on your boat, total weight, propellor, and battery capacity .

The range also depends on how fast you want to travel. If you go slowly you’ll have a much greater range.

For instance, at a slow speed (5 knots) Torqeedo’s Deep Blue 50R , a 50 kW motor (80 hp equivalent) with a 40 kWh battery, has a listed range of 33-100 nm. But at full throttle (20-25 knots), the listed range drops to 16-20 nm.

To get a better sense of what range to expect on your boat (at both low and high speeds), you can look at the manufacturer’s website. See our list of electric outboard brands below.

One of the great things about electric outboards is that they can use renewable power sources. So, for instance, you could plug your boat into a portable solar panel while picnicking and get an extra boost for the trip home.

Some electric outboard boat motors can even generate power! Motors with hydro regeneration capabilities can charge the batteries while the boat is being towed or under sail.

While hydro regeneration is a fairly new feature for electric outboards, some manufacturers, like EPropulsion, are offering it across their outboard product line.

Key features of electric outboard boat motors

Each electric outboard motor brand has slightly different standard offerings and add-on features. Here are some of the key features and options to look for.

• Waterproof.  Some electric outboards are fully sealed and designed to withstand immersion
• Remote controls. Choose between tiller and remote throttle controls
• On-board computers . Some electric outboards come with chartplotter connectivity, navigation functions, sonar, GPS anchoring, and autopilot features
• Built-in or stand-alone batteries.  Some of the smaller motors come with built-in batteries, while the larger ones have separate battery packs
• Battery monitoring and tracking systems  that calculate and display the remaining range in real-time
• Shaft length.  Electric outboards come in both short and long shaft lengths to accommodate a variety of applications.
• Hydro regeneration capabilities 

Electric outboard manufacturers

These electric outboard boat motor manufacturers (listed in alphabetical order) range from small startups to large companies and serve the North American market.

If you’re looking to learn more about what each of these companies offers (and how they compare) I’d highly recommend checking out the  Plugboats’ electric outboard guides and directories . Jeff Butler, the editor at Plugboats has done a great job of compiling motor specifications from across the market.

Headquartered in San Diego, California,  Bixby  makes a small electric motor system for kayaks, inflatable boats, canoes, and paddleboards.

Elco  has been building electric motors for 125 years and counts the likes of Henry Ford and Thomas Edison among their customers. Their award-winning electric marine motors range from 5 to 50 hp. The company is based in Lake George, New York, and its electric motors can be found on boats around the world.

Flux Marine

Flux Marine was founded by mechanical engineering Princeton grads and offers three outboard models—a 40 hp, 70 hp, and 100 hp. In 2021, they won an award for the best new green product at the Newport International Boat Show.

Joe Grez, a consumer product developer from Washington, invented the  EP Carry , a compact, ultralight electric outboard system because he was concerned about exposing his young daughter to the carbon monoxide (CO) emissions produced by gas outboards.

The EP Carry retails for $1,600 and is a great size for small vessels like dinghies, canoes, inflatable boats, and kayaks.

ePropulsion

ePropulsion , based in Guangdong, China, manufactures 3 to 9.9-hp electric motors for sailboats, fishing boats, as well as dinghies and tenders. They all come with hydro regeneration capabilities.

Mercury Marine launched the Avator 7.5 electric outboard (3.5 hp equivalent) in early 2023. The leading outboard manufacturer is currently developing more powerful 20e and 35e models which it plans to release later this year.

In 2023, Newport , a well-known US-based inflatable boat manufacturer, launched three small outboards ranging from 1.8 to 3 hp.

If you’re into fishing, you’re probably familiar with the Minn Kota  name, derived from MINNesota North DaKOTA, prime fishing country where the company has its roots. They introduced their first electric trolling motor back in 1934 and they’ve been making them ever since.

Pure Watercraft

Pure Watercraft  was founded by CEO Andy Rebele in Seattle in 2011. Their 25 kW (50 hp) motor starts at $16,500.

Ray Electric Outboards

Ray Electric Outboards is a 3rd generation family-owned business based in Cape Coral, Fl. They manufacture one outboard model that can be operated at different power ratings ranging from 10 to 22 hp.

Stealth Electric Outboards

The 50 and 75-hp  Stealth electric outboards  were developed by Scott Masterston of Houston, Texas.

German manufacturer,  Torqeedo , has been leading the propulsion industry for years and sells some of the best e outboard motors in the 1 to 80-hp range

Vision Marine Technologies  (formerly The Canadian Electric Boat Company). 

Based in Quebec, Canada,  Vision Marine Technologies  has been in the boating industry for 25 years and produced some very innovative electric boats. In 2021, they launched E-Motion 180E, one of the most powerful electric outboards on the market.

Electric inboard boat motors

Today’s electric inboard motors can provide anywhere from  3- to a whopping 330 hp (2 to 246 kW)  and are used in a range of applications from heavy displacement vessels to fast, planing powerboats.

Similar to outboards, the range on electric inboard engines will vary based on your boat, load, battery capacity, and boat speed (among other things).

However, with an inboard electric boat motor, you have the option of a hybrid motor which can significantly extend your range. We’ll discuss the pros and cons of hybrid boat motors later in this post.

Sailors may also want to consider choosing an inboard electric motor with hydro regeneration capabilities. These electric power motors can charge the battery while the boat is under sail.

DIY electric inboard boat motor conversion

One way to save money on an electric inboard is to do the installation yourself. There are a few DIY electric inboard boat motor conversion kits available on the market.

I’ve spoken with a few sailors who’ve had great success replacing their inboard diesel engines with these electric boat motor conversion kits from  Thunderstruck-EV , an electric drive manufacturer in Santa Rosa, California.

Key features of electric inboard boat motors

Each brand has a slightly different set of electric inboard motor options. Here are some of the key features and options to look for.

• DIY conversion kits
• On-board computers  and touchscreen display
• Waterproof  system components

Electric inboard manufacturers

US manufacturer, Elco Motor Yachts , has been building electric motors for over 125 years, having gotten their start in 1893, supplying electric boats for the Chicago World’s Fair. They have seven inboards ranging from 6 to 200 hp.

Electric Yacht

Electric Yacht  is a US supplier focused on providing plug-and-play electric motors for DIY installations on sailboats. Their electric propulsion systems range from 10 to 30. They’ve had over 450 installs in 10 years of production.

Oceanvolt  is a leader in regenerative systems and their electric inboard motors are popular among sailors. They offer shaft drive systems ranging from 6 to 60 hp.

Torqeedo, a German manufacturer, is the world’s leader in electric boat motors. They have two lines of inboards, one for displacement boats and another for fast planing boats. Their Deep Blue inboard systems range from 25 kW to 100 kW (40 to 135 hp)

Hybrid systems

Hybrid systems combine an electric motor and combustion engine, so you can cruise in silence (but know you’ve got enough gas to get home). These systems offer  many of the benefits of pure electric motors, without the limited range. 

If you want  additional power for onboard luxuries  like air-conditioning, hybrids can also provide a significant increase in house-side fuel efficiency.

The downside to any hybrid solution is that the systems are far more complex . Not only do they require more equipment, but, for an optimized system, you’ll need highly sophisticated software to manage multiple power sources and switch back and forth between diesel and electric.

Unsurprisingly, the increased complexity adds cost, making hybrids less economical than either a conventional or pure electric install.

Serial vs. parallel hybrids

As with cars, there are  two types of hybrid systems: serial and parallel.  A serial hybrid uses a generator to power a large electric motor connected to the drive shaft. Whereas, a parallel hybrid has both a conventional combustion engine and a small electric motor connected to the drive shaft.

There are plenty of factors to consider when choosing between a parallel and serial system. Marine mechanics and electrical expert, Nigel Calder, does a great job of explaining  serial and parallel hybrids  in detail.

In general, serial systems may be a better fit for boats that can get most of their propulsion energy from renewable sources (e.g., a sailing catamaran). Whereas, a parallel system makes more sense on boats that regularly require sustained propulsion (e.g.,  Greenline’s power yachts ).

Key features of marine hybrids

• Parallel and serial hybrid options
• Integrated energy management  systems

Marine hybrid manufacturers

Elco motor yachts.

Elco  manufactures serial, parallel, as well as a combined serial-parallel system. Their systems can be used on sailboats, trawlers, yachts, and boats up to 85′ feet.

Hybrid Marine Ltd.

Hybrid Marine  sells parallel hybrid systems in the 10 to 230 hp range. Beta, John Deere, and Yanmar’s hybrids all incorporate Hybrid Marine technology.

Finnish manufacturer,  Oceanvolt , offers serial hybrid systems for both sailboats and powerboats.

Torqeedo  makes hybrid systems for yachts up to 120 feet as well as powerful motorboats.

Electric pod drive and sail drive

Several manufacturers are now making electric pod and sail drives. These electric drive systems are more efficient and can save space onboard.

Electric pod and sail drive manufacturers

Electric Yacht  produces a range of sail drives that can replace diesel engines up to 75 hp.

propulsion  sells a 3 hp, 6 hp, and 9.9 hp fixed pod drive.

Oceanvolt’s  sail drives range from 6 kW to 15 kW (8 to 20 hp)

Torqeedo  sells a 40 hp and 80 hp equivalent electric sail drive as well as electric pod drives in the 6 to 25 hp range.

While it’s possible to power an electric motor with a conventional lead-acid battery, there are many  good reasons to upgrade to lithium-ion batteries.

Their increased usable  capacity is roughly double  what you can get out similarly sized lead-acid battery. More battery capacity means more range—and hours of fun—on your electric boat.

They also  charge more quickly  and have a  longer life span  than lead-acid batteries. Unlike flooded lead-acid batteries, which need to be watered, lithium-ion batteries are practically maintenance-free.

The downside is that lithium-ion batteries are far  more temperature-sensitive  and can’t be charged much above 113 F (45 C) or below 32 F (0 C).

They  can also present major safety issues . Lithium-ion batteries can go into what’s known as thermal runaway—a self-heating process that can cause the battery to catch fire.

Simply put,  lithium-ion batteries are NOT a drop-in substitute for lead-acid batteries.  They need to be specially designed for the marine environment and paired with a robust battery management system.

Electric motor manufacturers often provide complete solutions (including motor, batteries, and battery management system). It’s a good idea to work with a manufacturer with extensive marine experience and an ABYC-certified technician on any installation.

The other catch is that lithium-ion batteries  cost two to four times   as much as lead-acid  batteries. However, the increased capacity and longer life span may make lithium batteries a better value option over the long run.

Ready to catch the electric boating wave?

With ever more powerful and feature-packed electric options launching each year, it’s an exciting time to be in the market for a new motor or engine. If you have any doubts about whether an electric boat motor is right for you, head to your local boat show and see, first hand, what all the buzz is about.

Fiona McGlynn is an award-winning boating writer who created Waterborne as a place to learn about living aboard and traveling the world by sailboat. She has written for boating magazines including BoatUS, SAIL, Cruising World, and Good Old Boat. She’s also a contributing editor at Good Old Boat and BoatUS Magazine. In 2017, Fiona and her husband completed a 3-year, 13,000-mile voyage from Vancouver to Mexico to Australia on their 35-foot sailboat.

Douglas McQuilken

Sunday 30th of January 2022

Great article!

For those who wish to collaborate with prospective & current electric boaters, highly recommend this forum - https://groups.io/g/electricboats

Thanks for the suggestion, Douglas!

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Inboard Electric Boat Motors: A Comprehensive Guide

With increasingly powerful electric inboard motors released, what are your thoughts? Would you buy one to own a completely green boat?

In the past, many held a skeptical attitude toward inboard electric propulsion. The good news is that the electric boat motor has made a host of breakthroughs with cutting-edge technologies, such as the highly efficient LiFePO4 battery and regeneration for extended running time, etc.

This post will introduce the latest information and insights on the electric inboard boat motor to help you decide whether it’s time for you to invest in an electric inboard motor.

Table of content:

• What is a Boat Inboard Engine

Which Situation Suits Inboard Motor

• What is the Advantage of Inboards
• Inboard Motor Recommendations

What is a Boat Inboard Engine?

In contrast to the outboard motor with a marine engine outside the hull of a boat, an inboard boat motor is an engine housed within the hull of the watercraft.

In other words, an inboard boat motor, whether it’s powered by gas, diesel, or electricity, is mounted inside of a boat permanently and helps power a prop shaft through the hull.

Inboards are more desirable for sailboats, motorboats, commercial boats, workboats, and marine boats for city tours because they’re generally higher displacement engines with broader power ranges vs. the equivalent outboard horsepower ranges and tend to be smoother and quieter.

Actually, inboards are the best thing you can own for just going to watersports. They are also some of the easiest boats to work on since they are such a simple drive train.

For water sports, the inboard is safer because the person in the water would not be as close to the propeller or sharp skeg on an outboard, but a safe captain makes all the difference. You’ll probably get better and stiffer rudder torque and more power to pull multiple people or a huge tube with an inboard.

For sailboats, we highly recommend the electric inboard boat motor too.

Regarding dinghies that sailers bring during sailing, the electric outboard is suitable because it is easier to maneuver for docking and better for leaning on, and our top-selling electric outboards are Spirit 1.0 Plus (comparable to 3hp) with detachable floating batteries and Navy Evo (comparable to 6hp- 9.9hp) with hydrogeneration.

What is the Advantage of Inboards?

Did you get bothered by a variety of problems with gas engines or diesel engines on boats? Then consider switching to the less complex electric inboard boat motor.

Troubles with Traditional Marine Engines

One of the most conspicuous problems with conventional marine propulsion engines is mechanical. The pull-start diesel inboard engine boat that came with many boaters was a nightmare. For instance, the obnoxious low oil pressure beep of diesel, the need to inspect the coolant system, the oil level, the tightness of your belts and pulleys, etc.

The other main problem with internal combustion engines is greenhouse gas emissions. In order to achieve zero-emissions shipping, some countries have released regulations banning the use of conventional boat motors. So it’s wise to choose the electric boat motor for your watercraft from the beginning.

Note: CO2 emissions from energy combustion and industrial processes, 1900-2021

Source: www.iea.org

Source: www.climatecentral.org

Comforts with Electric Inboard Boat Motors

How fantastic it would be if we were just able to sail and not have to worry about being a diesel mechanic. A green boat with an electric inboard motor can make this come true.

As opposed to complex gas motor boats, an electric inboard motor has dramatically fewer moving parts to break, much less vibration from the propeller, no fuel filters, no oil leaks, no water contamination, no service headaches, and no rusting exhaust elbows or diesel bugs to be concerned about.

Electric Inboard Motor is so quiet that sometimes you don’t even notice its existence. While you take pleasure in journeys on the water with electric drives, like fishing, skiing, cleaning, cruising, and so on, what you can hear is peaceful, soothing, and gentle ocean waves, birdsongs, and gulls rather than bothersome noise that may scare off fishes and birds.

If you would like more power, in addition to having high-quality batteries, you can also convert the motor to create hydro-power, which is turned on by a switch, or just charge it with solar power. ePropulsion I-Series features hydrogeneration to collect electricity from wind and water.

Multifunctions of Battery Power

Electric propulsion is ideal for daysailers. One of the advantages is just having the opportunity for massive electric loads, such as those for electronic and cooking purposes (daysailors just need to bring kitchen appliances).

Inboard Recommendations

Whether offering propulsion for a newly built boat or for retrofitting a vessel, I-Series and H-100 electric inboard motors are a great option for sailboats, motorboats, fast yacht tenders, vessels for city tours, and so on.

ePropulsion clearly understands what aspects boat owners care about most and what they have complained about with their existing electric inboard motors: large and very complex to deploy, lack smart and user-friendly control system, unstable batteries, etc. With a mission to create a better sailing experience, we strive to develop I-series and H-100 electric inboard motors. The following two sections will elaborate on them.

I-Series Electric Inboard for 15-60ft Boats

With integrated modules, the I20 inboard boat motor takes up 60% less space and is more than 65% lighter than traditional internal combustion engines, and 30% lighter than other brands of electric inboard boat motors of a similar range. (Under same input power).

Smart System Architecture (eSSA) features a complete fault diagnosis system, so it can detect equipment failures to automatically shield and protect the continuous operation of the boat.

The Built-in IoT (ePropulsion Connectivity) is industry-leading, allowing boat owners to access cloud-based connectivity services without adding additional accessories.

As to the performance of speed and duration of ePropulsion I series electric inboard motors, we listed specific data for your reference.

• I10 Inboard Motor with a 10kWh Battery
• I20 Inboard Motor with a 20kWh Battery
• I40 Inboard Motor with a 40kWh Battery

Note: Depends on the type of boat, load, propeller, and conditions. Speed and range indications do not represent a legal guarantee.

H Series Electric Inboard for 30-120ft Boats

The H-100 (60-140kW) is an electric inboard motor with a full displacement of up to 200 tons, designed for large sailboats, catamarans, small passenger and cruise boats, commercial workboats, along with large cruisers or dinghies in fresh water.

The new H series electric boat motor will be suitable for various scenarios, including transportation, tourism, rescue, and patrol, as well as cleaning, fishing, and commercial markets, and it can also be applied to self-driving boats.

The complete solution for powerful electric drive systems

With the outstanding capacity of customizing the electric propulsion system of the whole boat, we have accumulated some successful cases of retrofitting boats and marine vessels in Europe already. The solution is modular, scalable, and flexible. According to different uses scenes, the H-60, H-85, H-100, and H-140 marine engines can easily expand their running range and running time by adopting a combination of various powers and batteries.

Larger torque

The H series electric boat motor inboard is equipped with a much larger torque, which helps the ship accelerate, gets out of danger during boating and leaves enough power to withstand the wind and waves.

Easier to use/operate

The response of starting the electric drive system is very fast, and you can switch from low power to high power in a short time.

Innovative electric boat motors are renowned for their instant torque deliveries. This will be a massive advantage to control the location and direction of the boat. The immediate response to electric boat drives makes transporting to shore so easy, especially suitable for ports with narrow berthing positions.

Shared Feature- LiFePO4 Batteries

It’s time to switch to our LiFePO4 battery from your lead-acid one.

The chemistry of both E-Series battery packs (10240 Wh / 96 V) and G102-100 battery packs (2 kWh – 9 kWh/ 48 V) is LiFePO4, which is 30% lighter but offers about 50% more usable capacity than AGM lead-acid batteries. In addition, AGM batteries can only endure for 300–500 cycles, whereas LiFePO4 batteries can last up to 3000 cycles.

The greatest significant benefit is that LiFePO4 is much safer than most other types of lithium in that it won’t catch fire when the cells are damaged.

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Everything electric boats and boating

Electric Saildrive and Pod Boat Motors

Plugboats Guides Motors News Motors For Sale

Welcome to what we believe is the most complete guide to electric saildrive and pod boat motors. It provides top line details for more than 150 individual motors sorted by power range, style and usage. It has been assembled to provide a single place where someone interested in electric marine propulsion can find comparative information for motors made all over the world.

You may also be interested in our other guides »» Guide to Electric Outboards Under 5kW »»  Guide to Electric Outboards Over 5kW »» Guide to Electric Inboards »» Guide to Electric Trolling Motors »» Guide to Electric Boat Batteries

»» Plugboats also has the world’s largest and most complete Directories of over 600 elect ric boats, motors, batteries, accessories, solar panels and rental/charter companies

Information on using this Plugboats Guide

The top of this web page is the Illustrated Guide with photos of the motors and specifications to the right.

Sortable/Searchable Table

At the bottom of the page is a table that can be searched if you know you are looking for a certain type of motor (i.e. pod or saildrive), a certain power range, or for a specific weight/length of boat. If you are going to use the table, the page is best viewed on a computer rather than mobile or tablet.

Illustrated Guide

The motors are organized in alphabetical order by manufacturer, then by style of motor, i.e. fixed pod, steerable pod, saildrive and then by power of motor within those listing. For many styles there are multiple powers of motor available and where that is the case we have made it as easy as possible to line up the motor with its specifications. i.e. if there are three power of motor with different weights, it will be noted as kW: 2kw, 2kw, 3kw • Weight: 10kg, 12kg, 15kg. For some manufacturers the variations are more complicated and we have done our best to make it simple and understandable.

There is a lot of variety in the way manufacturers detail the technical attributes of their products. We have tried to take the most common measurements and assemble an ‘apples to apples’ comparison. See the notes below in ‘Measurements’

The photographs and drawings are from the manufacturers’ websites and are not shown in any consistent scale.

kW • Voltage • Current • HP: Not all manufacturers list all of these specifications. We have included the specifications available and where not available have used the notation N/A.

kW is the kW rating provided by the manufacturer. Most websites do not indicate whether it is input or output kW. When it is indicated, we took the output.

Voltage is most often referred on the sites as ‘Voltage’. Some indicate nominal or peak, we have used nominal and indicated if peak is also referenced.

Current Is noted when the manufacturer supplies the information. Generally it is measured in amperes: A. In some cases the manufacturer uses Amp Hours: Ah and we have noted it where that is used.

HP : is ‘HorsePower equivalent’ so that you can get an idea of the power of the motor in comparison to a HP rating you might be more familiar with. Where available, these measurements come from the manufacturer’s website, and different manufacturers measure the HP in different ways. Some even use metric horsepower, which is slightly different from imperial horsepower. Again, we have tried to make it as apples to apples as possible. (For general guidance, 1kW is round one and a third HP 1kW=1.3HP, or the reverse is that 1HP is around three quarters of a kW: 1 HP = .75kW).

Static Thrust. Torque, Efficiency: This is probably the specification that has the most variability. We have simply given whatever information the manufacturer has published on their website, when available.

Range and Running Time : We have not included estimates of range or running time because it depends on too many factors: battery size (sometimes type also), water conditions, speed, etc. The exceptions are for the ePropulsion and Torqeedo models which have batteries from the manufacturers specifically matched to the motors and therefore provide estimates on their websites.

General : If a manufacturer publishes a specification, we have tried to include it here, even tough other manufacturers may not include the same type of measurement.

Information on this page updated February 4, 2024

You may also want to check our Directory of Electric Boat Motor manufacturers, dealers and distributors around the world, or the Plugboats Marketplace of electric boat motors for sale.

Manufacturers in this Buying Guide: Aquamot • Bellmarine • Combi • Electric Yacht • ELECTRINE • EP Technologies • ePropulsion • E-TECH • Fischer Panda • Gardenergy • Kräutler • Navigaflex • Oceanvolt • Piktronik • Rim Drive Technology • Seadrive • TEMA • Torqeedo

Aquamot was founded in 2003 by engineer Siegmund Hammerstrom and has grown to be a leading manufacturer of electric motors and accessories, including outboards inboards, chargers and batteries. They have two lines of fixed pod motors: Trend and Professional, as well as a line of steerable pods that line up with the power ranges of the Professional line.

Aquamot Trend Fixed Pod 1.1FM and 1.6FM

• Recommended Boat Size: <1.8 tons
• kW : 1.1 / 1.6 • Voltage : N/A • Current : N/A • HP : 3.5 / 5 • Static thrust : 89lbs
• Motor Type : Brushless AC asynchronous • Passive water cooled (motor underwater)
• Weight (kg) : 10.2 / 11.3
• Propeller/RPM : 3 blade fixed, folding optional • RPM : N/A
• Other : Includes: Integrated/removable lithium battery (0.64kWh), charger, display, emergency kill switch. Optional: spare battery, customized compensation wedge, folding propeller ($US 835). Warranty: 2 year limited
• Country of Manufacture : Austria
• Price (MSRP) : $US 2,200 / $2,600

Aquamot Trend Fixed Pod 2.2FM and 4.3FM

• Recommended Boat Size: <4 tons kW : 2.2 / 4.3 • Voltage : 24 / 48 • Current : N/A • HP : 6.4 / 11 • Static thrust : 124 lbs / 197 lbs
• Motor Type : Brushless AC asynchronous• Passive water cooled (motor underwater) Weight (kg) : 12.2 / 13.9
• Other : Includes: Controller, display, basic cables, emergency kill switch. Optional: customized compensation wedge, folding propeller ($US 835). Two year limited warranty.
• Price (MSRP) : $US 3,300 / $3,750

Aquamot Trend Fixed Pod 11.0FM to 25.0FM

• Recommended Boat Size: N/A
• kW : 11 – 25 • Voltage : 48 – 96 • Current : N/A • HP : 28 – 45 • Static thrust : n/a
• Motor Type : Brushless AC asynchronous• Passive water cooled (motor underwater)
• Weight (kg) : 44.3 – 48.9
• Propeller/RPM : 3 blade fixed • RPM : N/A
• Other : Includes: Controller, display, basic cables, emergency kill switch. Optional: customized compensation wedge. Warranty: 2 year limited
• Price (MSRP) : $US 7,150 / $9,915

Aquamot Professional Fixed Pod F10e to F250e

• kW : 1 – 25 • Voltage : 24 – 96 • Current : N/A • HP : 45 – 339 • Static thrust : n/a
• Motor Type : Sensor-less AC asynchronous • Passive water cooled (motor underwater) • Efficiency : 92%
• Weight (kg) : 12 – 50
• Propeller/RPM : 2 blade fixed, folding/feathering optional • RPM : N/A
• Other : Integrated anode, permanently usable for salt or fresh water, maintenance free. Operating efficiency 92%, Included: Custom-made compensation wedge, Controller, throttle, battery monitor, cables, Optional: display, folding/feathering propeller. Warranty: 2 year limited
• Price : N/A

Aquamot Trend Steerable Pod UF10e to UF250e

• Other : Optimized cavitation plate. Permanently usable for salt or fresh water, maintenance free. Operating efficiency 92%, Included: Custom-made compensation wedge, Controller, throttle, battery monitor, cables, Optional: display. Warranty: 2 year limited

»» Bellmarine website

Bellmarine is a very well established electric boat motor company with a history going back to 1999. Along the way they merged with a battery accessory manufacturer and have now been purchased by Transfluid, a large scale industrial motor manufacturer. Bellmarine offers a wide range of electric boat motor configurations, with their saildrive system consisting of their own motor combined with Yanmar drive mechanics. They range from 2kW to 20kW in power with either air or liquid cooling. They also offer a regeneration option. You may want to download the full Bellmarine catalogue

Bellmarine SailMaster Air Cooled Models 2A, 5A, 7A, 10A, 15A, 20A Download .pdf brochure

• kW : Bellmarine uses Nominal and Intermittent kW measurements. These are the intermittent figures: 2, 5, 7, 8, 10, 15, 20 • Voltage : 48V except for the 8A, 15A and 20A models which are 96V • Current : N/A • HP : 2.5, 6.5, 9, 10.5, 13, 20, 25
• Motor Type : Permanent Magnet AC • Air cooled
• Weight (kg) : N/A
• Propeller/RPM : propeller not supplied • RPM : Motor: 1500, Propeller 750 except for 20kW which is Motor 3000, Propeller 1500
• Other : Includes Yanmar SD25 Sail drive leg with 2:1 reduction, motor, controller, , stainless steel motor support brackets.
• Country of Manufacture : Netherlands

Bellmarine SailMaster Liquid Cooled Models 3W, 7W, 10W, 15W, 20W Download .pdf brochure

• kW : Bellmarine uses Nominal and Intermittent kW measurements. These are the intermittent figures: 3, 7, 10, 15, 20 • Voltage : 48V: for all models except 8A, 15A and 20A   –   96V:  Models 8A, 15A, 20A • Current : N/A • HP : 4, 9, 13, 20, 25
• Motor Type : Permanent Magnet AC • Liquid cooled
• RPM : 1500: Models 2A, 5A, 7A, 8A, 10A, 15A   –  3000: Model 20A 

»» Combi website

Combi Outboards was founded in 1979 in Giethoorn (‘the Dutch Venice’) to supply rental boats with clean electric power. It is now a leading international supplier of electric propulsion solutions for the maritime market. Combi manufactures inboards, pods, hybrids and outboards. There are six pods ranging in power from 1kW to 3.5 kW: 1, 1.5, 2, 2.5, 3 and 3.5kW. They are available both as fixed pod or steerable pods.

Combi Nautic Fixed Pod/Saildrive Download .pdf brochure

• kW : 1.0 – 3.5 • Voltage : 24 (1.0kW + 1.5kW), 48 (2.0kW – 3.5kW) • Current : 42A – 73A • HP : 4 – 9
• Motor Type : Asynchronous AC • passive water cooled Weight (kg) : N/A
• Propeller/RPM : 3 blade fixed – 220mm or 230mm • RPM : 1050 (3.5kW 1300) Other : “Easy Connect” system delivered Plug & Play for owner installation. 

Combi Nautic Steerable Pod Download .pdf brochure

The Steerable Pod Nautic models have the same specifications as the Saildrive models above.

• Motor Type : Asynchronous AC • passive water cooled
• Propeller/RPM : 3 blade fixed – 220mm or 230mm • RPM : 1050 (3.5kW 1300)
• Other : “Easy Connect” system delivered Plug & Play for owner installation. 

Electric Yacht

Electric Yacht is one of the premier US suppliers of saildrives. They have developed a Plug-n-Play system that has been engineered for quick, simplified installation as well as long term durability. Their systems offer regenerative power while under the sail. 10 years of proven production with over 450 installs. 3 Year Warranty

Electric Yacht QuietTorque™ 10.0 Sail Drive

• Recommended Boat Size: <6 tons – 34’ (10m)
• kW : 10 • Voltage : 48 • Current : 200A • HP : 10.5
• Motor Type : Brushless PMAC
• Weight (kg) : 45
• Propeller/RPM : 2 or 3 blade, fixed or folding, 12”  – 16” • RPM : N/A
• Other :  Installs through 9” hole, Anodized aluminum frame and waterproof throttle,Digital Display of: State of Charge (SOC, Voltage, Current, Power, Motor RPM, time to discharge based on current power consumption, updated in real time, Programmable regeneration. 3 Year Warranty. 
• Country of Manufacture : USA
• Price (MSRP): $US 11,995

Electric Yacht QuietTorque™ 20.0 Sail Drive

The Electric Yacht Quiet Torque 20 is essentially the 10.0 with twin motors

• Recommended Boat Size: <12 tons – 45’ (14m), catamarans 40’-46’ (12-15m)
• kW : 20 • Voltage : 48 • Current : 400A • HP : 21
• Motor Type : Brushless PMAC X 2
• Weight (kg) : 77 Propeller/RPM : 2 or 3 blade, fixed or folding, 12”  – 18” • RPM : N/A
• Other :  Installs through 9” hole, Anodized aluminum frame and waterproof throttle,Digital Display of: State of Charge (SOC, Voltage, Current, Power, Motor RPM, time to discharge based on current power consumption, updated in real time, Programmable regeneration. 3 Year
• Warranty. 
• Price (MSRP): $US 14,695

Also: Electric Yacht QuietTorque™ 30.0 Sail Drive (boats <14 tons) Electric Yacht QuietTorque™ LC 45 Sail Drive (boats <17 tons) Electric Yacht QuietTorque™ LC 60.0 Sail Drive (boats <22 tons)

• Recommended Boat Size: 14 tons – 22 tons, 45’- 60′ (15-18m)
• kW : 30 – 60 • Voltage : 48 – 96 • Current : 300Ah – 600Ah • HP : 48 – 65
• Motor Type : Brushless PMAC X 2 • liquid cooled
• Weight (kg) : 100 – 106
• Propeller/RPM : N/A
• Other :  Installs through 9” hole, Anodized aluminum frame and waterproof throttle, Digital Display of: State of Charge (SOC, Voltage, Current, Power, Motor RPM, time to discharge based on current power consumption, updated in real time, Programmable regeneration. 3 Year Warranty. 
• Price (MSRP): $US 19,995 – 23,495

»» ELECTRINE website

ELECTRINE is a Korean manufacturer which has focused on maritime electrification since 2010, when the idea of electric mobility was still relatively uncommon. The company was known as LGM until 2020 and has had a consistent R&D effort for many years. They manufacture electric outboards, inboards and saildrives as well as accessories and Lithium-ion batteries using a Carbon Nano Tube heat exchanger technology. Ther are 6 motors in their eSaildrive line, ranging from 8 kW to 110 kW.

ELECTRINE eSaildrive line: S-8, S-16, S-25 (shown), S-40, S-80, S-110

• Recommended Boat Size: Daysailer / Racing / Monohull /Multihull
• kW : (Max) 8, 16, 25, 40, 90, 110 • Voltage (Vdc): 48, 48, 96, 96, 345.6, 345.6
• Motor Type : N/A
• Weight (kg) : 40.5, 46.5, 50.5, 172, 198, 218
• Other : Hydrogeneration on 8kW and 16kW models. ELECTRINE also makes batteries customized for the motors
• Country of Manufacture : Korea
• Price (MSRP): N/A

EP Technologies

»» ep technologies website.

EPTechnologies is a complete marine propulsion provider for electric and hybrid vessels. The company specializes in custom electric and hybrid systems, but also has ‘off the shelf’ motors, including a range of saildrives. Their Electric Turnable Saildrive offers 360-degree rotation, the key advantage being that no additional thruster is required behind the boat. Other saildrives (SD-25, SD-60, SD-15) have a fixed lower unit. All saildrives are include a complete system utilizing batteries designed and built by EP Technologies.

EP Technologies Turnable Saildrive

• kW : 25 – 60
• Voltage (VDC): 100 – 800
• RPM : 500 – 2000
• Other : 360° Rotatable, Electric servo motor, Joystick Control
• Country of Manufacture : Denmark
• Price : Contact EP Technologies

EP Technologies Saildrives: SD-25, SD-50, SD-15

• kW : SD-25: SD-60: 25, 39, 60, SD-15: 65, 95
• Voltage (VDC): SD-25: 48, SD-60: 100 – 800, SD-15: 400 – 800
• RPM : SD-25: 1000 – 2000, SD-60: 500 – 2000, SD-15: 500 – 2000

ePropulsion

»» epropulsion website.

ePropulsion was  founded in 2012 by three engineers from the Hong Kong University of Science and Technology (HKUST).  The company continues to have a strong engineering culture where each engineer is individually responsible for creating as much value for users as possible. ePropulsion offer two pod models based on their outboards: the 1kW Spirit and 3kW Navy.

Click here to view motors from ePropulsion dealers in the Plugboats Marketplace

ePropulsion Pod Drive Evo 1.0 , 3.0, 6.0

• kW : 1, 3, 6 • Voltage : 40.7, 48 • Current : 25A, 62.5A • HP : 3, 6, 9.9 Static Thrust : 71, 132.6
• Weight (kg) : (Including integrated battery) 14.1, 15.6
• Propeller/RPM : Spirit: 2 blade, 28 × 14.7 cm (11′ × 5.8″), Navy: 2 blade, 26 × 17.1 cm (10.2″ × 6.7″), RPM: Spirit 1200, Navy 2300
• Other : Hydrogeneration, Includes battery and wireless remote controller (cable option also), Spirit has 1.1 kWh lithium battery, Navy has 3.0 kWh
• Country of Manufacture : Hong Kong/China

»» E-TECH website

E-TECH is a subsidiary of boatbuilder Starboats that was started in 2008 because they were dissatisfied with other electric motor offerings in the market at the time. The company has developed fixed pods, steerable pods and outboard motors that all utilize an in-water BLDC (BrushLess DC permanent magnet) pod motor in a watertight aluminum casing. There are 5 pod models available in both fixed pod and steerable pod configuration. All of these are equipped with the ruddershaft, tube and steering lever. There are also 4 models of high torque pods available only in fixed pod format.

Click here to view motors from E-TECH dealers in the Plugboats Marketplace

E-TECH 4 POD, 7 POD, 10 POD, 15 POD, 20 POD Link to Fixed Pod Motors • Link to Steerable Pod Motors Download .pdf brochure

• kW : 4.3, 7.5, 10.9, 16.6, 19.5 • Voltage : 48, 48, 48, 72, 96 • HP : ≈ 6, 10, 15, 22, 27 • RPM : 1350, 1350, 1470, 2240, 2200
• Motor Type : Brushless PMDC • water cooled
• Other :  Includes controller, display with battery monitor, joystick (side- or top mounting), 2m steering cable, 5m connecting cables between controller and steering position (standard 5 meter).
• Country of Manufacture : Poland

The four High Torque E-TECH PODH engines are designed for those applications where a very high torque is needed.

E-Tech High Torque PODH: 13 POD, 18 POD, 23 POD, 35 POD Download .pdf brochure

• kW : 11.9, 16.7, 21.5, 33.7 • Voltage : 48, 72, 96, 144 • HP : ≈ 16, 23, 29, 45 • RPM : 760, 1140, 1520, 2500

Fischer Panda

»» Fischer Panda

Fischer Panda is one of the world’s best known manufacturers of marine generators but are also manufacturers of high quality electric boat motors, sometimes marketed under the ‘Whisperprop’ name. They have an “EasyBox” system that is intended to take the guesswork and complication out of purchasing electric boat motors.

Fischer Panda 48V Underwater Drive System (Easybox) Download .pdf brochure

• kW : 3.8 – 20.0 • Voltage : 48 • Current : N/A • HP : 5 – 25
• Motor Type : Brushless Permanent Magnet (PMAC)
• Weight (kg) : 18.7 – 120
• Propeller/RPM/Torque : Propeller not included • RPM : 600 – 2500 Torque (nM) : 28 – 320
• Other :  Includes: Fischer Panda EasyBox control unit, control panel, throttle Options: Propeller, propeller protector, battery bank, charger, shore power connection.  
• Country of Manufacture : Germany

Fischer Panda EasyBox HV High Voltage System Fischer Panda Download Centre

• Recommended Boat Size: <40 tons
• kW : 50, 80, 100 • Voltage : 360 – 420 • Current : N/A • HP : 65 – 125
• Weight (kg) : 42
• Propeller/RPM/Torque : 5 blade fixed • RPM : 1200 / 1900 Torque (nM) : 398 – 400
• Other :  These motors are generally designed for use by small public transportation ferries, commercial working vessels and privately owned leisure yachts. Systems should be customized.

»» Gardenergyy website

Gardenergy is an Italian company established to offer ‘a simple and reliable product featuring cutting-edge technology’. They use the same motors in a variety of ways, cleverly configuring them for outboard, inboard shaft drives, and either fixed pods or steerable pods.

Gardenergy Pod

To see options and download .pdf brochures, go the Gardenergy site and click on ‘Links’. A pop up will appear with options. There is also an option for price list and a Configurator which can help with system assembly and pricing.

There are five Gardenergy pods with power input of: 2kW, 4.3 kw, 6kW, 8kw, 10kW. They are available as fixed or steerable pods.

• kW : 2, 4.3, 6, 8, 10 • Voltage : 48 except for 2kW which is 24V • Current : N/A • HP : 2.5, 5.5, 7.5, 10, 13
• Motor Type : PMAC
• Propeller/RPM/Torque : 3 blade fixed, folding available • RPM : 2kW: N/A, 4.3kW: 1450, 6kw: 1600, 8kW: 1750, 10kW: 1950
• Country of Manufacture : Italy
• Price (MSRP): Download MSRP Price List $US 3,975 – 6,625

»» Kräutler website

Kräutler is a long-established Austrian manufacturer of industrial electric motors. They began construction of electric boat motors in the 80’s mainly because they could not find a product that would live up to the standards of founder Oswald Kräutler. They make motors for industrial and ship use as well as recreational boats and probably offer the widest range of sailpods and saildrives on this page with everything from small .5kW steerable pods to electrically rotatable saildrives with power up to 30kW.

An explanation about the Kräutler section of this guide: The Kräutler fixed pods are available with AC motors (ACV) or DC motors (GPV). The AC are for smaller boats. They also come in two different configurations: fixed propeller and folding propeller. In the interests of making this page shorter, we have divided them in to the motor types for the written descriptions but have shown you the fixed and folding options in the images. In the table each of the motors has a separate listing. NOTE: The GPV motors are only suitable for short use in salt water.

Krautler Submersible Flange Motor Pods with D C motors Download .pdf brochure

• MOTOR TYPE: GPV
• Recommended Boat Size: <1.9 tons
• kW : 0.5, 0.8, 1.6, 2.2 • Voltage : 24 except for 2.2kW which is 36V • Current : 21, 34, 67, 61 • HP : 0.5, 1.0, 1.8, 2.5
• Motor Type : GPV: DC motor with permanent magnets, continuous control 
• Weight (kg) : 14, 15, 20, 20
• Propeller/RPM/Torque : 3 blade fixed or folding (see intro note above) • RPM : N/A • Torque : N/A
• Other :  ATTENTION: GP motors are only suitable for short use in salt water. Includes: Motor, bracket, electric regulation system, throttle, status display monitor, battery monitor, cables, battery master switcher & fuse, propeller, anode. Operating efficiency 85%
• Price (MSRP):

Krautler Submersible Flange Motor Pods with AC Motors Download .pdf brochure

• MOTOR TYPE: ACV
• Recommended Boat Size: <10 tons
• kW : 1.8, 2.0, 4, 8, 10 • Voltage : 24 (1.8, 2.0kW) 48 (4, 8, 10kw) • Current : 100, 107, 104, 202, 250 • HP : 2.3, 2.5, 5, 10, 13
• Motor Type : ACV: AC brushless three phase asynchronous motor  
• Weight (kg) : 21, 29, 29, 40, 50
• Other :  Includes: Motor, bracket, electric regulation system, throttle, status display monitor, battery monitor, cables, battery master switcher & fuse, propeller, anode. Operating efficiency 75% – 83%

Krautler Submersible Pod with Tiller Handle Download .pdf brochure

• MOTOR TYPE: ACV or GP
• Recommended Boat Size: Sailboat: <10 tons, Powerboat: <6 tons
• kW : 0.5 – 10 • Voltage : 24, 48 • Current : 21 – 250 • HP : 0.5 – 13
• Motor Type : ACV: AC brushless three phase asynchronous motor • GP:  permanent magnet with continuous control 
• Weight (kg) : 15 – 54
• Propeller/RPM/Torque : 3 blade fixed • RPM : N/A • Torque : N/A
• Other :  Includes: Motor, bracket, electric regulation system, throttle, status display monitor, battery monitor, cables, battery master switcher & fuse, propeller, anode. Tubes/diaphragms available for installation. Standard shaft length: 450mm. Operating efficiency 75% – 85%

Krautler Saildrive Compact Download .pdf brochure

• Recommended Boat Size: <4 tons
• kW : 2.0, 3.0, 4.0 • Voltage : 24, 36, 48 • Current : 104, 100, 99 – 250 • HP : 0.5 – 13
• Motor Type : AC brushless three phase asynchronous motor with continuous control 
• Weight (kg) : 42, 42, 42,
• Propeller/RPM/Torque : Propeller not included • RPM : N/A • Torque : N/A
• Other :  ATTENTION: SDK drives are only suitable for short use in salt water. Includes: Motor, saildrive gear, base plate for lamination (depending on motor size), electric regulation system, throttle, status display monitor, battery monitor, cables, battery master switcher & fuse. Operating efficiency 80%, 83%, 84%

Krautler Saildrive Fixed Download .pdf brochure

• Recommended Boat Size: Sailboat: <30 tons, Powerboat <12 tons
• kW : 2.5 – 30.0 • Voltage : 24 – 144 • Current : 104 – 370 • HP : 3.5 – 40
• Motor Type : AC brushless three phase asynchronous motor with continuous control. MOTORS 15.0 – 30.0kW are water cooled.
• Weight (kg) : 45 – 91
• Other :  ATTENTION: Water cooled drives are only useable in seawater with 2-circle water cooling. ATTENTION: SDK drives are only suitable for short use in salt water. Includes: Motor, saildrive gear, base plate for lamination (depending on motor size), electric regulation system, throttle, status display monitor, battery monitor, cables, battery master switcher & fuse. Operating efficiency 85% – 88%

Krautler Saildrive Mechanical Rotatable: 2 x 45° Download .pdf brochure

All of the Krautler motors with specs shown in the fixed saildrives above can be installed with a mechanical rotatable option shown here or electric rotatable option shown below. The Sail-Drive is supplied with a fiberglass foundation base, which can be laminated to the hull (depending on motor size). For existing Volvo and Yanmar foundations the Sail-Drive is equipped with an adapter plate and can be screwed directly on the existing foundation.

Krautler Saildrive Electric Rotable: 2 x 90° or 360° Download .pdf brochure

All of the Krautler motors with specs shown in the fixed saildrives above can be installed with an electric rotatable option shown here. The Sail-Drive is supplied with a fiberglass foundation base, which can be laminated to the hull (depending on motor size). For existing Volvo and Yanmar foundations the Sail-Drive is equipped with an adapter plate and can be screwed directly on the existing foundation. The electrical rotating mechanism includes an actuating drive with gearbox, electric regulation system for the drive, a steering lever and display.monitor indicating propeller position

»» Navigaflex website

The innovative Navigaflex motor has a Patent Pending design in which the motor itself retracts and pivots and can attached to the boat as an outboard or inboard motor. The motor is made with a minimum of parts, a light construction and is adaptable to all boat hulls. The standard motor can also be ordered with a “booster” to double the power for up to 2 minutes.

Navigaflex Motor

• Recommended Boat Size:  2 tons / 8m – 16 tons / 18m kW : 6kW, 8kW, 10kw, 15KW • Voltage : 48 (nominal) • HP : 8, 11, 13.5, 20
• Motor Type : Brushless Permanent Magnet (PMAC) • Water cooled (10kW and 15KW)
• Weight (kg) : 54 (4KW) – 68 (15KW)
• Propeller/RPM : 2 blade fixed •  RPM : N/A
• Other : Retractable motor, Option to regenerate the current under sails, Digital motor controller with touch screen and mobile phone connected remotely.
• Country of Manufacture : Switzerland
• Price : $US 8,000 – 16,000

»» Oceanvolt website

Oceanvolt is one of the best known names in saildrives and its ServoProp regenerating system is regarded as one of the first and best. It is difficult to provide full information about their systems because their website encourages customers to provide information for customized solutions. These are some basics

Click »» here to see Oceanvolt motors for sale from vendors in the Plugboats Market

Oceanvolt SD Saildrive See more detailed information

• Recommended Boat Size:  < 80 ft / 25m
• kW : 6, 8, 10, 15 • Voltage : 48 • HP : 8, 11, 13.5, 20
• Motor Type : Synchronous permanent magnet • Closed circulation liquid cooling provides cooling and lubrication
• Weight (kg) : 42.5, 42., 46.5, 46.5
• Propeller/RPM : Propeller not included •  RPM : 2200 • Gear Reduction Ratio : 1.93: 1
• Other : Includes: Battery communication kit, hydrogeneration feature • Sold separately: Batteries, Charger, Propeller • Sail Drive with 1.93:1 reduction. Closed circulation liquid cooling provides cooling and lubrication. 10kW and 15kW systems include 15.2kWh Li-ion battery bank, charger
• Country of Manufacture : Finland
• Price : $US 13,500 – 45,000

Oceanvolt Servoprop Saildrive

The Oceanvolt ServoProp is a patented variable pitch sail drive that ‘combines a high efficiency sail drive with the most powerful hydro generator on the market’. Unique feature is the possibility to turn the propeller blades more than 180 degrees. The software controlled variable pitch sail drive adjusts the pitch of the propeller blades automatically so that the power generation and power output are optimal. The blades are designed to give the system maximum efficiency in forward, reverse and regeneration. With the blades set to the neutral sailing position, the propeller creates extremely low drag similar to the drag of a feathering propeller. ServoProp is capable of generating more than 1 kW at 7-8 knots & 3 kW at 11-12 knots.

»» Piktronik website

Piktronik is an Austrian-Slovenian company working on the research, development and production of components for electrical vehicles (EV) and boats. Their pods are available in a variety of configurations that vary by the power output. We have noted that below. They also sell motors as complete systems with batteries and chargers.

Piktronik UWM1 – UMW10 On arriving at the linked page, there are links for each motor to download more information

• kW : 1, 2, 5, 6.5, 10 • Voltage : 16, 17, 30, 30, 30 • Current : 50, 92, 120, 150, 200 • HP : 1.4, 2.7, 6.8, 8.8, 13.6
• Motor Type : PMSM (permanent-magnet synchronous)
• Weight (kg) : 18, 23, 25, 51, 95
• Propeller/RPM/Torque : 2 blade fixed – 4 blade fixed • RPM : 1100, 1200, 1850, 1200, 1000 • Torque (nM) : 7, 14, 27, 51, 95
• Other :  Aside from the complete system detailed below the motors alone come in different configurations: 1kW and 2kW: steerable pod or fixed pod, 5kW: steerable pod, fixed pod, transom mount, 6.5kW: steerable pod or transom mount, 10kW: steerable pod or transom mount
• Country of Manufacture : Slovenia

Piktronik SYS Systems 1kW – 10kW On arriving at the linked page, there are links for each motor to download more information

Piktronic sells their motors in complete system kits for each of the motor sizes detailed above. Complete system includes: motor, motor controller, display monitor, cables, siwthces, fuses, battery charger, remote comtrol, steering arm, installation tube, tiller handle, propeller

Rim Drive Technology

Click here to view RIM Drive Technology motors for sale in the Plugboats Marketplace

»» Rim Drive Technology website

Rim Drive technology is a Netherlands company with a line of rim motors in which the propeller blades are affixed to a rim rather than a central hub. There are no wearing parts within the motor and much reduced chance of weeds or other debris snagging or clogging. The motors are available as outboards, pods, azimuths and thrusters. The company offers complete systems or standalone batteries, controllers, monitors and other accessories. The pods in the Guide are sorted as 24V, 48V and 48V+. All pods are available with extended shaft options to reduce hull effects on the rim drive water flow for quieter and smoother operation.

24V Pods POD 3.0, POD 5.0

• kW : 3.0, 5.0 •  Voltage : 24 •  HP : 6.5, 11.0 • Thrust (kg) : – 31, 62
• Battery : Sold separately, recommended LiFePO4 available from Rim Drive
• Running Time : Suggested 4-5 hours with recommended Rim Drive battery pack
• Shaft Length (cm) : N/A extended shaft length available
• Propeller Diameter (mm) : 86, 133
• Weight (motor only) (kg) : 3.5, 5.0
• Other : One year warranty for non-commercial use, Completely waterproof (IP68), Efficiency 90+, Includes 2m cable set
• Price : €3,340, €4,000

48V Pods: 5 motors POD 0.5, POD 3.0, POD 5.0, POD 11.0, POD 15.0

• kW : 0.5, 3.0, 5.0, 9, 11, 16 •  Voltage : 48 •  HP : 1, 6.5, 10, 20, 28 • Thrust (kg) : – 7, 31, 62, 156, 250
• Running Time : Up to 7 hours with suggested Rim Drive battery pack
• Propeller Diameter (mm) : 65, 86, 133, 212, 341
• Weight (motor only) (kg) : 2.5, 3.5, 5.0, 14.0, 70.0
• Price : €3,300, €3,400, €4,000, €6,850, €18,000

96V, 110V, 400V Pods POD 25.0, POD 30.0, POD 50.0

• kW : 25, 30, 50 •  Voltage : 96, 110, 400 •  HP : 42, 52, 74 • Thrust (kg) : – 380, 400, 750
• Running Time : Average 3 hours with suggested Rim Drive battery pack
• Propeller Diameter (mm) : 341, 341, 341
• Weight (motor only) (kg) : 70, 70, 75
• Price : €25,000, €25,000, €48,000

Steerable Pods (8 models) Steerable POD 3.0, 5.0, 8.0, 11.0, 15.0, 25.0, 30.0, 50.0

• kW : 3, 5, 8, 11, 15, 25, 30, 50 •  Voltage : 48, 48, 48, 48, 48, 96, 110, 400-550 •  HP : 42, 52 • Thrust (kg) : 31, 62, 120, 156, 195, 350, 400, 750
• Weight (kg) : 21.5, 23, 32, 32, 37, 110, 110, 110
• Other : Rotatable up to 200 degrees, Waterproof hull passthrough, Stainless steel or glass fibre seal available, Salt water resistant (IP68), Motor controller included, Joystick, steering wheel or CAN controlled
• Price : €7,350, €8,225, €12,075, €12,375, €14,900, €31,995, €31,995, €55,500

»» SeaDrive website

SeaDrive is a Norwegian manufacturer that has an innovative approach to pods, saildrives and all electric boat motors for which they received a nomination for a 2019 DAME Award. The concept is that the basic motors can be configured: fixed pods, steerable pod, a saildrive or lift-up azimuth side pod – also with the ability to have the propellers arranged for push propulsion or pull propulsion.  There are also regenerative versions available. The pod motor systems come in three power ratings: 7.5, 15 and 30.

SeaDrive Modular Pods/Saildrives/Lift-Up Azimuths

• kW : 5-7.5, 10-15, 20-30 • Voltage : 48, 96, 144 • Current : NA • HP : 7.5, 15, 32 • Static Thrust: 90, 160, 300
• Weight (kg) : Motor Weight: Aluminum: 20, Bronze 23. Total Weight differs by configuration
• Propeller/RPM/Torque : Fixed or folding • RPM : N/A • Torque N/A
• Other :  re-generative versions and TABLET/PC control.
• Country of Manufacture : Norway

»» TEMA website

TEMA is a Croatian company that makes highly regarded electric motors that can be purchased alone or in systems for marine, industrial and power generation applications. Their saildrive system uses their SPM132 series of very efficient compact permanent magnet motors. The motors operate on either DC or AC voltages and can be powered from battery systems (48 96Vdc) or generators.

TEMA SYS Systems 1kW – 10kW Download .pdf of Systems configuration Download .pdf of SPM Motors

• kW : For each of their models TEMA has dual figures – kW output at 1800/3600 RPM. The 5 models range in listed power from 12/19kW to 35/57kW • Voltage : There 48 and 96 Voltage availble for all models. • Current : 50, 92, 120, 150, 200 • HP : At 1800/3600 RPM they range from 25/39 to 47/76
• Motor Type : PMAC (Permanent Magnet AC), PMS (Permanent Magnet Synchronous) • Air cooled
• Weight (kg) : 73, 93, 110, 130, 148
• Propeller/RPM/Torque : Propeller not supplied • RPM : 1800/3600 across all motors • Torque (nM) : Maximum: 70, 111, 145, 178, 205
• Other :  Includes all components: e-motor, motor controller, saildrive, marine throttle, display, plug and play wiring. Efficiency: 95%.
• Country of Manufacture : Croatia

»» Torqeedo website

Torqeedo is the world’s leading manufacturer of electric outboards. The company was founded in 2004 by Dr Christoph Ballin and Dr Friedrich Böbel when they decided they could build a better electric motor than the one on the boat Dr. Ballin had just purchased. The company offers trolling motors, inboards, outboards and pod motors and works with BMW’s battery division as well as partnering with many of the world’s premier boat designers and manufacturers. It may be useful to download the full Torqeedo Catalogue

Torqeedo Cruze FP Pod 2.0 – 4.0 Operating instruction .pdfs can be downloaded from link above

• kW : 2, 4 • Voltage : 2kW: 24, 4kW: 48 • Current : N/A • HP : 6, 9.9 • Static Thrust 155 lbs, 189 lbs
• Motor Type : Brushless External Rotor Motors with Rare-earth Magnets • Operating efficiency 56%.
• Weight (kg) : 15.4, 15.8 Propeller/RPM/Torque : 3 blade fixed or folding • RPM : 1300
• Other :  GPS on-board computer & display: Real-time speed, input power. Operates with lithium or AGM/lead-gel batteries, exact battery status and remaining range available when using Torqeedo battery. Emergency magnetic kill switch.
• Price (MSRP): $US 4,549, 4,999

Torqeedo Cruze FP Pod 10.0 Operating instruction .pdfs can be downloaded from link above

• Recommended Boat Size: <10 tons kW : 10 • Voltage : 48 • Current : N/A • HP : 20 • Static Thrust ≤ 405 lbs
• Weight (kg) : 33.5
• Propeller/RPM/Torque : 5 blade fixed or folding • RPM : 1400
• Other :  Includes: Remote throttle, integrated on-board computer with GPS-based range calculation, 70 mm² cable set (3 m) including fuse and main switch, plug connector. 2 year warranty.
• Price (MSRP): $8,999

Torqeedo Cruze FP Saildrive 10.0 Operating instruction .pdfs can be downloaded from link above

• kW : 10 • Voltage : 48 • Current : N/A • HP : 20 • Static Thrust ≤ 405 lbs
• Weight (kg) : 37

Torqeedo Deep Blue 25 Saildrive

• Recommended Boat Size: <50 tons
• kW : 25 continuous, 33 peak • Voltage : 345 • Current : N/A • HP : 40 • Static Thrust ≤ 405 lbs
• Motor Type : Brushless External Rotor Motors with Rare-earth Magnets • Operating efficiency 55%.
• Weight (kg) : 125, 314 total system including 1 battery
• Propeller/RPM : Propeller : not included • RPM : 1200
• Price (MSRP): On Request with requirements input

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OCEANVOLT SYSTEMS

Oceanvolt power and propulsion systems consist of several key components; a powerful regenerating motor, an ergonomically designed control lever,  a propulsion battery bank, a charger and a motor controller.

Oceanvolt offers complete electric power and propulsion systems for either shaft or sail drive configurations.

shaft drive

AXC Modular Shaft Drive Motors

AX Shaft Drive Motors

ServoProp Sail Drives

SD Sail Drive Motors

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Cabo Rico’s Classic Cutter

Bob Perrys Salty Tayana 37-Footer Boat Review

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Preparing Yourself for Solo Sailing

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• Systems & Propulsion

Electric and Hybrid Propulsion for Sailboats

Practical sailor looks at the players in the developing field of electric auxiliary engines.

How soon will electric auxiliary propulsion be available to everyman? That depends on whom you ask. Opinions differ widely not just on what type of drive system might surge to the forefront, but even on whether the concept itself is viable. While a handful of companies forge ahead, notably Glacier Bay and Electric Marine Propulsion on this side of the Atlantic, some expected participants are waiting on the sidelines.

Photos courtesy of Manufacturers

One of the big issues that divides promoters and detractors alike is whether the appropriate way to go in a sailboat is with a pure diesel-electric drive train, with a hybrid electric drive with a diesel generator as back-up, or as a pure electric drive with regeneration capability. We’ll take a look at these and other options later in this article. For now, the short answer is that no single approach suits every sailor all the time.

Simply put, in the diesel-electric system, the electric motor runs only when the diesel-driven generator is running. Such arrangements have long been employed in railway locomotives, submarines, and commercial vessels of many types. In the hybrid system, a large bank of batteries provides the energy for the electric motor and the diesel generator recharges the batteries. On the face of it, the hybrid system offers a certain degree of redundancy in that, assuming the batteries are kept well charged, the boat has a measure of emergency power should the generator fail at an inopportune moment. The hybrid also is capable of recharging its batteries when sailing: Driven by the turning propeller, the motor becomes a generator.

Each of these approaches has its strengths and weaknesses, and while we’ll leave it to their developers to work out the technical issues, we would like to urge anyone contemplating installing an electric drive, or purchasing a boat that has one, to first look very closely at how they expect to use the boat. There’s more entrained in the choice than in picking a flavor at Baskin-Robbins. More on this later.

Among the electric drives currently available in one form or another, or as components, the big variable is operating voltage. Motors are available that run on 24, 36, 48, 72, and 144 volts, and, in the case of Glacier Bay’s diesel-electric system with Ossa Powerlite technology, 240-volt DC. Each supplier will discourse at length on the merits of their voltage choice, but an inconvenient fact haunts the entire field: High-voltage DC is deadly, potentially more so in some circumstances than AC.

While neither form of high-voltage is “safe,” we have a lot more experience with AC aboard recreational vessels than with high-voltage DC. An extensive body of knowledge exists on which to base AC installations so as to make them safe as well as reliable. High-voltage DC is used in a variety of marine and non-marine commercial applications, but these installations are well protected from access by untrained operators.

What voltage constitutes high voltage? That, again, depends on whom you talk to. The American Boat & Yacht Council (ABYC), which sets voluntary standards for the marine industry, defines it as 50 volts and above. Prompted by rapid adoption of high-voltage services in small commercial craft and bigger yachts, though not specifically in propulsion systems, the ABYC is in the process of drawing up guidelines for voltages higher than the 48 volts covered by existing standards.

An absence of standards might not deter individuals from installing an electric drive, but it might impede widespread adoption of the technology. If a surveyor can’t state in an insurance survey that a boat is built according to ABYC standards, that could affect its insurability.

Jim Nolan, who manages the underwriting department for BoatUS, said the company has no clear cut guidance regarding insuring boats with electric propulsion. Each boat is dealt with on a case-by-case basis. A new boat with a factory-installed system would be a good deal easier to underwrite than a one-off or do-it-yourself project, especially in the absence of a standard practice. Lagoon Catamarans’ 72-volt-DC hybrid system, for instance, has qualified for the European standard (CE) certification on the strength of following industrial standards that apply to such applications as fork-lift trucks. Anyone contemplating an electric drive would be well advised to discuss it ahead of time with an insurer and even get a surveyor involved from the outset.

Because of the safety issues surrounding the voltages involved in electric propulsion, Fischer Panda has decided to limit its DC product line to boats weighing 10 tons or less. A company representative we spoke to said that while Fischer Panda currently sells DC generators up to 48 volts in the USA for marine use, it “won’t touch” high-voltage DC because it’s lethal.

A proposed collaboration with Catalina Yachts to fit a diesel-electric system in a Catalina-Morgan 440 never came to fruition due to budget constraints, according to Fischer Panda. But in Europe, Fischer Panda teamed up with Whisperprop to equip a Bavaria 49. (Beyond the fact that one of its boats was used, Bavaria Yachts was not involved in the project.) According to Fischer Panda, after evaluating the Bavaria project, the company decided that the diesel-electric AC system is a niche product that wouldn’t interest their prime market: original equipment builders.

“Although the AC system has some advantages in the improved response of the electric motors … and the quietness of the system, the desired fuel efficiency and weight savings were not evident,” Fischer Panda reported.

Fischer Panda considers the DC system to be more suitable for its North American customers. Although it’s limited in output due to its limited battery voltage of 48 volts, it is still able to power multihulls up to 10 tons.

Currently, much of the movement toward electric drives is taking place in the catamaran world. This makes sense when you consider that a single diesel generator can, in theory, provide all the boat’s electrical needs and also take the place of two diesel-propulsion engines. Taking the lead in the field, Lagoon Catamarans introduced in 2006 the Lagoon 420. Originally offered only as a hybrid, it now is also available in two diesel versions. Corsair Marine is building the Corsair 50 catamaran around the Glacier Bay diesel-electric drive, but the boat’s launch date—formerly set for this summer—has been postponed.

Dick Vermeulen, president of Maine Cat, tried the Glacier Bay system in a prototype power cat, but it failed to meet performance expectations, so production models will have conventional diesels. A number of other cat builders have announced hybrid or diesel-electric projects, but feedback on how they perform is scan’t.

So much for the mainstream—but backwater sailors will go their own way, as they always have. As more vendors and components enter the market, the options for do-it-yourselfers or custom-boat customers become broader and more attractive. However, before going ahead with an installation, make sure it’s appropriate to how you plan to use your boat, and even then be prepared to adapt the way you sail to take best advantage of the system’s characteristics. Here’s a rundown of the various types.

Electric Drive Only

Duffy Electric Boats has for years been building electric launches and lake boats that have the simple capability of puttering around in sheltered waters for a period of time determined by battery capacity and speed maintained. A battery charger powered by shore power charges the batteries overnight. Transferring that approach to a sailboat up to about 25 feet used for daysailing and kept near an electrical outlet shouldn’t be too difficult. It won’t offer the assurance of diesel when trying to get home against current or wind, but a proven 36- or 48-volt system will keep you out of uncharted standards territory.

For a bigger boat, more power, a greater range, or a combination of these requirements, it will be necessary to install a large battery bank and almost certainly will entail going to a higher voltage to keep the amps and the cabling needed to carry them manageable. The boat’s range under power will be limited by the weight of batteries, and while lighter lithium-based technology is on the horizon, for now the standard is lead/acid. The fast charging, but expensive pure lead thin plate (PLTP) Odyssey batteries have attracted particular interest among propulsion enthusiasts.

Electric Drive with Regeneration

The next level up in complexity is a “reversible” system. When the boat is sailing, the propeller turns the motor, which then becomes a generator. The electricity it makes is used to recharge the batteries. The capability to regenerate extends the boat’s potential range, but the drag on the propeller slows the boat measurably. One hour of regen will not restore the power consumed by one hour of motoring, but if sailing time sufficiently exceeds motoring time, this arrangement offers considerable range.

A regenerating system does have the potential to overcharge the batteries once they become fully charged and the boat continues to sail fast. The solution is, ironically, to give the motor some “throttle,” which reduces the drag on the propeller and consequently the power output. This phenomenon gives rise to a new technique, that of “electro-sailing” in which sails and an electric motor complement each other. At present, the “throttle” must be adjusted by hand, but developers are working on automatic controls. Field trials of existing regen motors such as the Solomon systems suggest that a small regen motor’s ability to match the output of a much higher-rated diesel have been overstated.

Hybrid Electric Drive

A hybrid system adds to the mix an onboard generator, which is used primarily to maintain charge in the batteries, both those for the propulsion motor and for the house services. This arrangement extends the boat’s capability to lie for long periods at anchor, independent of shore power for electricity and without the need to go sailing for the sole purpose of charging the batteries. A hybrid can motor constantly, as long as there is fuel, but it cannot sustain full speed for long periods. This is because the generator is usually rated at a far lower horsepower than that required to drive the boat at full speed.

Diesel-Electric Drive

In a pure diesel-electric, the electric propulsion motor runs only when the generator is running. Storage batteries are not needed for propulsion purposes, and the generator is the source for all onboard electrical power needs. The rationale behind diesel electric lies in the relationship between a diesel engine’s rate of fuel consumption and the load it’s working under. It burns fuel more efficiently when heavily loaded than when lightly loaded. When the diesel engine is disconnected from the propeller, it can be controlled so that it is working in the upper range of its efficiency regardless of how fast the propeller is turning. Nigel Calder’s series of articles in Professional Boatbuilder magazine (www.boatbuilder.com) beginning with the June/July issue delves deeply into the efficiency discussion surrounding these engines. Systems on large vessels are built around multiple generators that switch on or off according to the power demands of the moment. Translating those efficiencies into a smaller boat scenario has proven to be challenging.

Hype vs. Experience

Maine Cat’s Vermeulen, on the company’s website, describes the sea trials he performed in the Maine Cat 45, a power catamaran. He began with a Glacier Bay diesel-electric system with two 25-kW generators, each weighing about 550 pounds.

“With both generators putting out their full power of 25 kW each … our top speed was a disappointing 8.4 knots, and the assumption that electric horsepower was somehow more powerful than conventionally produced horsepower was in serious doubt.”

He replaced the propellers with a pair with less pitch, which allowed the electric motors to reach their full rating of 1,100 rpm, but that only increased the speed to 9.1 knots.

“These are about the same speeds and fuel burns we get on our Maine Cat 41 sailing cat … powered by twin 29-horsepower 3YM30 Yanmar diesels with saildrives and two-bladed, folding propellers.” At the time he installed them, the 25-kW generators were the highest power available from Glacier Bay.

Vermeulen replaced the diesel-electric system with twin 160-horsepower Volvo diesels. At 9.1 knots, they together burned 2.2 gallons per hour, considerably less than the 3 gallons per hour that the Glacier Bay system burned at the same speed. With the twin Volvos maxed out at 3,900 rpm, the boat made 24.5 knots.

Also among the unconvinced is Chris White, well-known designer of ocean-going catamarans. “To date, I’ve not seen any system that makes sense for a cruising boat,” he says, but he might change his mind, “if someone can show me by building one that delivers an advantage in performance, weight, or cost.”

White sees the current bubble of interest in diesel-electric drives as a fad. In the end, he says, you’re getting the horsepower the diesel creates at the crankshaft, which is basically the same whether it’s delivered to the prop via a conventional reduction gearbox or via a generator and an electric motor. Besides, he says, diesel engines and diesel fuel are understood and available anywhere in the world you might take a sailboat. Complex, electronically controlled electric motors are not.

White’s reservations notwithstanding, it’s in the world of catamarans that we’re seeing most of the applications. At first sight, it does seem logical that replacing three diesel engines—two propulsion and one generator—on a fully equipped cruising cat would result in fuel savings. Still, if the generator is big enough to drive the boat at cruising speed (which in a cat is expected to be in the vicinity of 10 knots) and run the air conditioning at the same time, it will be overkill for the times it’s only needed to operate the boat’s services. For this reason, commercial and military diesel-electric systems employ multiple generators that can be switched on and off according to the power demand of the moment.

Corsair Marine hopes that by installing a diesel-electric system in its 50-foot catamaran, it will be able to descend the weight spiral. Where a conventional installation would involve two 75-horsepower saildrives plus a 6-kW genset, it’s fitting a pair of 28-horsepower electric motors, one 25-kW generator, and a 40-amp, 230-volt battery bank. It expects to save about 700 pounds in equipment weight, some of it through the use of high-voltage, low-current systems, which will in turn reduce the rig requirement, thus the structural weight, and so on toward an estimated overall weight savings in the thousands of pounds.

Corsair’s David Renouf estimates that the boat will cruise at 8 knots and be capable of short bursts at 10. He admits that, until the first boat is launched, his information is “based on extrapolation, not proven numbers.” He says that some clients will add a second 25-kW genset to assure longer periods at 10 knots. Currently, the project is running behind schedule, with a launch scheduled before the end of the year.

Cost and Other Benefits

At the present time, there appears to be no reason to install any proprietary electric drive of any description in the expectation of bettering the economics of a standard diesel drive. The motors and their electronic controllers are sophisticated and expensive. A battery bank sufficient to provide a useful motoring range is a big investment in weight, space, and money. When you add a generator and its peripherals, the cost and weight take another upward leap.

Only the simplest system will begin to pay itself off in terms of fuel not burnt, and then only if the boat sees a great deal of use. A diesel-electric system designed to closely dovetail with the way you use the boat may prove to be more efficient over time than a conventional diesel installation, but until enough systems have been installed and used and data from that use compiled and compared, we can’t know that.

So why even consider going electric? Cleanliness and silence of operation are two qualities that make electric propulsion an attractive proposition for a sailboat, but in order to enjoy them, we have to accept the limitations they impose.

A hybrid or a diesel-electric system enables us to have a single fossil-fuel power source for both propulsion and onboard appliances, but whatever fuel we might save as a consequence of motoring more efficiently for a couple of hours will be inconsequential if we run the generator all night to power the air conditioning.

Conclusions

As we go to press, pickings are slim for sailors looking for an electric solution to the diesel problem. Suppliers of components are few, prices are high, and the feedback on long-term reliability is nonexistent. On top of all this is the elephant in the room: the unexplored safety ramifications that accompany high-voltage DC.

However, none of this should deter the dedicated tinkerer who has funds to match his curiosity and who can live within the parameters imposed by electric propulsion.

Practical Sailor encourages our readers to explore the technology, because ultimately, it is the experimenters who bring us the equipment we eventually come to take for granted.

• Pricing Electric Power for a 30-foot Sailboat
• Special Report
• Electric Engines
• Success in the Real World is a Matter of Perspective

RELATED ARTICLES MORE FROM AUTHOR

What your boat and the baltimore super container ship may have in common.

I have gotten excited about repowering my Freedom 30 with an electric motor. A fellow Freedom 30 owner completed his refit about 8 months ago and is very happy with the result, although he wishes he had gone with larger Lipo batteries. He chose a motor from electricyacht.com which sells a 10KW package (quietTorque 10) including motor, performance display, throttle and shaft coupler for $6K. Batteries and charger are extra. The motor does does feature a regen capability. Figure a $10K investment. Big bucks for sure but equivalent to a yard installed diesel repower. I would do the install myself.

I am not a cruiser but have done some lengthy passages from San Francisco to Hawaii. Ideal conditions for regen. I expec between regen and a hundred watts of solar, I could have kept the bank topped up the whole way down despite AP loads, etc. The way back? Not so much. Realistically you would need a small generator and a good stock of gas if you wanted to do much motoring, Having said that, one of the boats that sailed down there with me came home with an outboard as his aux power. I think he had ten gallons of gas.

But I am not planning ocean passages in future, I will be sailing the SF Bay and coastal cruising. When I think about eliminating the engine noise, engine maintenance, fuel tank and tank maintenance, diesel hoses, diesel smell, diesel soot, diesel leaks, r=two boxes of hoses and spares. oil changes, coolant changes, transport and disposal of all the waste to the local recycling facility, lugging fuel jugs down to the boat, storing fuel, filling fuel, buying fuel, worrying about spilling fuel. I mean it just goes on and on.

Frankly, I can’t wait. In terms of range, well, I plan to get a hefty battery bank but I also intend to become a better sailor. I’ll slow down and do more sailing. Gee wiz, what a concept. I’ll be more mindful of time and tide, I’ll take advantage of favorable currents and I’ll be ready to anchor and chill when they are not favorable.

Meanwhile, Elon and his competitors are improving battery technology rapidly. Couple of years from now maybe I double range. But, by then, I won’t be worrying about it because I will be a real sailor.

I look forward to reading an update on the state of electric sailboat propulsion 13 years later…

Most of the time we leave the dock, motor for under half a nautical mile to get out of tiny Wilmette harbor and get the sails up, turn off our much abused Yanmar 3GMF, sail around, turn on the engine, lower the sails, and travel another half a nautical mile back to the dock. Almost all at a very low RPM. But, on occasion we motor or motor sail long distances for hours on end, so a battery only system would not work. But how nice it would be if we had electric propulsion for getting in and out of the harbor.

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Betts Boat Electrics are authorised installers for Oceanvolt systems and can provide sales, installation and service to ensure a  successful  project.

Click here to contact us about our inboard drive solutions.

The AXC  range of shaft  drives has been designed in 10kW modules with a maximum of 40kW

Oceanvolt has a range of sail drives from in SD6kW - 15kW

all capable of regeneration 

The newest edition Servo Prop has the the most efficient regeneration of the saildrive models

See their web site for full details

When you  purchase an Oceanvolt electric boat drive from BBE you get a complete drive train.

Motor,  batteries, master switch board, generators, solar and load management  supplied  as integrated system.

All to AMSA & Australian Standards.

Explore how to integrate the 48V DC electrical system with the lower 12 & 24 voltages that most of marine electrics and electronics utilise

Electric Motor

Please note:.

The following information is in regards to our initial set up. It has been almost 5 years since we wrote this. Many upgrades and improvements have been made since then. All can bee seen on our Youtube Channel. Updated wiring diagrams, specs and photos will be coming soon. In the meantime, much of the below information is still accurate and I’m sure you will find it useful. And the answer to our most asked question is YES, we still love our electric motor!

WHY ELECTRIC?

An electric motor . . .

Is not for everyone..

Lets first take a look back in time when “production” boats became popular in the late 60s early 70s, the intent was to make an inexpensive boat the average family could afford and handle with limited sailing experience and knowledge. As a result, one of their requirements was the ability to move the boat in difficult situations. This is where the “auxiliary engine” was coined. But, for many, it has become the primary means of maneuvering their boat. Yes, there are places in the world you can’t sail, like the Panama Canal. But, there are often alternatives where you CAN sail.

“We have yet to use our motor for more than 30 minutes at a time.”

As of today, November 2016, we have sailed over 3000 miles up the east coast of the United States and through the Bahamas to Haiti. We have yet to use our motor for more than 30 minutes at a time. The majority of use comes when we drop the mainsail and back down on our anchor to set it. Most of our sailing has been offshore. But, we have also sailed on the ICW and recently sailed 25 miles up the Cape Fear River to Wilmington, NC. We have sailed under many bridges, some on set schedules, others open on demand. In all cases, we sailed under. We have found that having a solid plan and the patience to wait for the right weather and tide is the key.After all, we own a sailboat. They are inherently slow. We are not in a rush. We love the idea of being self-sufficient. But, for those who sail with schedules, are short on time, lack the patience to sit out a wind hole, feel the need to power their boat to hull speed, enjoy maintaining a diesel engine, or are just set in their ways, then an electric motor probably isn’t the right choice.

Want to learn even MORE…?

Of course we would love for you to stick around and read this page all the way to the bottom, but, we have tucked in many distractions (i.e. links) along the way. Don’t feel bad if you digress, we know you’ll be back. If you want to just jump feet first into all things “electric sailboat” Electric Seas is a good place to start. It’s a great resources community and features several other electric sailboat stories for you to enjoy.

ANOTHER POTENTIALLY GREAT RESOURCES…. 

“My Electric Boats” by: Charles Mathys. 

Although this book is currently on our Amazon wish list, we have not read it yet. But, it is the only one we could find on the subject and, for only $15, it looks promising. If you read it before we do, let us know what you think!

You don’t need a diesel . . .  

For ocean passages..

Many people have written in and commented that an electric motor is only good for day sailors who weren’t going very far each day, and that you need a reliable diesel engine for long distance cruising. But we feel like the opposite is true. Since we don’t have a dock to tie up to and charge our batteries each night, we rely on sailing to recharge our system. The longer we sail and the more sun we get, the more power we make. Because we don’t have a 9-5 to return to at the end of a fun weekend out on the boat, we have no schedules requiring that we make it back to the dock on time, no matter what the wind is doing. So, we feel that an electric motor, depending on your sailing style, can be adapted to any boat. But, you have to be willing to work around the one major draw back, range.

“We have no schedules requiring that we make it back to the dock on time.”

Range is the one major downside to an electric motor. But, with a sailboat, and some adequate sailing skills, we have found we really don’t need a motor as much as we originally thought. For those who do have schedules, the possibility of a hybrid system may work well. It encompasses all the benefits of an electric system with the added back up of a diesel or gas genset rated to supply adequate power for extended motoring. Some companies even offer an electric motor, like this one, that can be installed in parallel to an existing diesel motor. So the majority of motoring is done with the traditional diesel, however for short periods of time, like moving around the marina, the electric drive can be used instead. This also incorporates the added benefit of capturing power from the spinning prop while sailing, often referred to as “regeneration” or “regen”.

Our conversion to electric . . .  

Started with our motor..

We found the motor on ebay.com, knew it worked and that was about it. We chose this specific motor for three reasons:

• It was rated at 4.8kW at 36v which was adequate for our needs.
• It was overbuilt for an industrial application. This meant it had robust parts and easy to source replacement brushes.
• The motor cost us $125! Since this entire “Electro-Beke” project is just one big experiment, we tried at every corner to keep our expenses minimal.

Our motor weighs 110 pounds, which is quite a bit more than its brushless DC siblings like those used in the existing electric boat market. Although it is probably a little less efficient, its components are much more robust and durable. It is heavy duty, low cost and provides adequate power, with the added bonus of being simple and easy to find parts for. The only parts we will likely ever have to replace are the 8 carbon brushes that transfer electricity to the motor armature (the part that spins on the inside). Depending on use, they can last for many years without wearing out, and for about $80 we can buy a complete replacement set to have onboard. That’s it, virtually maintenance free, with only 1 moving part, the motor itself is relatively simple. On our boat, simplicity is often the defining factor for equipment selection.

This motor happens to be wired with separately excited field and armature (or SEPEX). It just means that we have a lot more control over the motors power output. We can tune it down to have more low end torque, or up to gain high end speed. This will allow us to customize the power output we need for our specific boat. A few other types of motors out there include, Series , and Permanent Magnet that only have one set of coils. Each type has its own benefits and drawbacks. But we won’t get into any of that here. If you would like to know even more about DC motors, click HERE .

we didn’t buy new . . .

Because we received quotes from three different companies:.

• Here’s our quote from OceanVolt for their AX8 motor.
• Here’s our quote from Annapolis Hybrid Marine for a Thoosa 7000HT motor. Read their prediction for power consumption and battery drain.
• Click here to see some data and predictions from Electric Yacht for their Quite Torque 20 motor.

Our entire set up . . .

Cost us just $1,400..

As you can see by the above quotes, The motors and supplementary wiring are all in the $10,000 price range. That doesn’t include a battery bank. Our motor and wiring cost us just under $500. Many of our components were refurbished, used or salvaged from boats being demolished, including some of the wiring. The battery bank and additional tools, like wire crimpers and cutters were another $500. So, for about $1000, we installed our Electro-Beke system. Our charging system ended up costing us only $400 thanks to a few amazing companies who joined our Uma Angels Family and supplied the major components. Find out more about our charging system in the “Charging” section below.

That Breaks down to:

$500 _ for the motor, controller and supplementary wiring. $500 _ for the batteries. $400 _ for the solar charger, panels and bimini modifications.

Power required . . .

To push our boat and yours..

Our motor has an 8hp rating. For those accustomed to gas or diesel engines, this may not seem like much power. But, the rating systems used for gas engines and electric motors are so different that comparing the numbers is almost meaningless. It comes down to the way the two types of motors use their energy and torque curves, which is quite different. According to the research we have done, a 1 hp gas (or diesel) engine can push 500 pounds of displacement to hull speed in calm conditions. Now, the sources disagree a little here, but as a rule of thumb a 1hp electric motor can push about 3 to 3.5 times more displacement than its petrol equivalent. So a 1hp electric motor, drawing 750W, can push about 1500 pounds of displacement.

“Hull speed’ and ‘redundant power’ weren’t something we worried about in our system.”

Our boat displaces 13,500 pounds. so, 13,500 / 1500 = 9hp electric motor., now 1hp (of electric) draws about 750 watts. so, 9hp x 750w = 6.75kw electric motor..

At 48V, our motor should give us 6.3kW, which is slightly less than what we would need to push our boat to hull speed in calm conditions. But that is something we never intend to do. It takes a lot of power to push a displacement boat to hull speed. So the slower you go, the greater your range will be. However, it takes a long time to cover that distance. So, there is a sweet spot right around 4 kts (see graph to the right) where you make good headway, while being conservative with your power consumption. Of course, these are merely suggestions. Real world conditions are rarely perfect and adding 30% redundancy is often recommended by many motor companies. 

We only use our motor for close quarter maneuvering where sailing isn’t an option, like a marina, or tight anchorage, so “hull speed” and “redundant power” weren’t something we worried about when designing our system. We often sail on and off the hook and choose places to anchor with few boats around. 

Power | Speed | Range

Hover over any point to see exact data. For example, it is estimated that at 2.7 kts our motor will draw 600 watts (blue), giving us a range of 65 nautical miles (grey). This graph is based on a 14kW Lithium battery bank and a high end motor/controller combo.

Here are some great companies . . .

That install, sell, or can help answer your questions..

Thunderstruck-EV  and EV-West  are staffed by great people who would love to hear from you and help answer any questions you may have. They both offer DIY kits that will suit the needs of any boat. They can also help source adequate battery banks, help with solar and even find local experts to assist with installations as well. 

If you’re looking for a more “plug and play” set up, check out the companies below. They represent the best in the industry and will gladly customize a set up for your specific needs and provide a detailed quote.

Elco Motors

elcomotoryachts.com

[email protected]

1 (877) 411-3526

Oceanvolt SEA

oceanvolt.com

[email protected]

+358 10 325 5281

clean-e-marine.com

[email protected]

+1 (410) 353-4348

Electric Yacht

electricyachtsocal.com

[email protected]

1 (855) 339-2248

Electroprop

electroprop.com

[email protected]

+1 (805) 455-8444

WANT TO LEARN EVEN MORE…?

Here is another great article about “How much electric power do you really need? !!! !!!

INSTALLATION

Getting down to the Nuts and Bolts

For the complete parts list and wiring diagram, scroll down..

There is a lot to talk about here. Hopefully you can follow along and not fall asleep. Like…I …….am…….right….nowwwww(yawn)www…  SLAP !!! Ok! I’m awake. Where was I. Right, wiring.

With no degrees or formal training in electrical engineering (and no, they didn’t teach us this stuff in architecture school), we had a lot of learning to do. Here we were, with a big heavy electric motor we knew nothing about, a boat it could theoretically push and the dream it would all work in the end. Now all we had to do was figure out how to get the motor to spin the prop. Sounded simple enough…right?

“…all we had to do was figure out how to get the motor to spin the prop.”

This step, of course took the longest. Since all our components were used, refurbished or salvaged, we had to test everything. We then started wiring the system in pieces in the salon and testing those. We then modified, adjusted, replaced and fabricated new systems and tested those. In all, it took us 9 months from motor purchase, to moving boat. Granted, not all of that time was devoted to installing the motor. We did have a few other projects on the side.

There are four main sections to our electric motor installation:

• The motor controller
• The batteries
• The wires that connect it all together

The motor we talked about previously. In all honesty, the main concern when sourcing a motor, is that it has enough power (watts) to push your boat to the speed you would like. The second concern is that it will work with the voltage of the components you choose. 12/24/36/48/72/96V are all common. The general rule, is that the higher the voltage, the fewer amps need to be pushed through the system to attain the same wattage. With this in mind, we have found that 72/96V systems tend to be more expensive than similar 48V set ups and, pushing a boat requires much less power that pushing a car. So, we’re not worried about running hundreds of amps through the system. Although rated at 36V, we run our motor at 48V so we can utilize available golf cart components for the rest of our systems, which are also inexpensive and abundantly available. For our boat, we designed the system to handle 150 amps. This would give us a theoretical output of just over 7kW (48V x 150A = 7.2 kW). If you were paying attention earlier, you might notice that our motor is rated for only 4.8kW at 36V. That is a continuous rating however. It can handle more, but cannot sustain it for long periods of time without some external cooling system. But, because there are times when we need all the power we can get, like stopping or backing down on the anchor, we decided to run our system with a higher amperage rating to accommodate that need.

CHECK OUT THESE PHOTOS OF OUR FINAL INSTALLATION.

(As usual, click to enlarge)

The Motor Controller

This little box is the heart of an electrical conversion. Similar to the head of an ICE (internal combustion engine), it controls the speed at which the electric motor spins. It does this by breaking up the power stream coming in from the batteries into tiny little pulses. This is called Pulse Width Modulation or PWM. There are many different types of controllers out there. In general, if you found a motor with standard voltage range, there is a controller on the market that will work for it. Some are more complex than others. Some offer built in regen capabilities, while other require computer programing and digital displays. 

Our controller is a Curtis 1209B. It is designed to run a series motor, but since we got it for such a good deal, we made it work with ours by only using it to power the armature. See the wiring diagram below for more details. This controller is not fancy. It is weather proof, simple and robust. If you haven’t figured it out by now, we love simple and robust. 

The Batteries

We will explain more below in the “BATTERIES” section. But for now, as long as you can create a battery bank that can be wired to produce the required voltage for the rest of your system, then you’ll be fine. Also keep in mind how much space and weight the bank will require. Ours fit perfectly where our old fuel tank used to be and helped offset all the weight we lost by removing the tank and the old diesel motor. For typical lead acid banks,  at 36V you will need 3 -12v or 6-6V batteries. A 48V bank will require 4 or 8 respectively and so on. Although you can purchase massive deep cycle batteries with equally large aH ratings, we don’t see the value of them since it is very difficult to maneuver them into tight spaces on a boat. Ideally, if you can afford them, a lithium bank would be the best for an electric motor conversion. We’ll talk more about them in the “WHAT”S NEXT” section below. 

All our wires our tinned copper or “Marine Grade”, although, we despise that term since it often just means “more expensive.” The majority of which, we scrapped off of boats that were being demolished at the boatyard. What we couldn’t find for free, we purchased from a local discount marine store that sold surplus marine components. This allowed us to spend very little for all the wiring. 

For the most part it is all oversized, but when it comes to wire, the bigger the better. There are many useful online calculators that can help give an idea of what size wire will be appropriate for a given application. If your wiring is undersized, the system will lose some efficiency. For the most part this is of no concern. However, in extreme circumstances it will heat the wire to the point of melting things. For example, we undersized the cables connecting the motor controller to the armature, after a 15min full power test at the dock, we melted off the heat shrink tubing on the terminal lugs. It was quickly replaced by something much more beefy and hasn’t been a problem since. 

O yeah, One More Thing . . .

The motor mount. .

Oops, almost forgot. Somehow we had to keep the motor inline with the transmission and securely mounted to the boat.  We built and re-built 6 different mounting brackets prior to the one we have now. Each being fabricated after hours of sketches and models were developed. We didn’t have to modify the motor any or the transmission itself. However, we did modify the original transmission adapter plate that was used to attach it to the back of our Westerbeke.  We then securely attached the transmission to the hull of our boat. This allowed the motor to float in front of it, leaving the transmission to absorb any thrust from the prop. 

We fabricated the brackets out of steal since it is easy to work with and weld. Once we settled on a final design, we epoxied and painted the brackets and motor with engine enamel. We’re quite pleased with the final outcome. All the exposed metal is protected from corrosion and it is very securely mounted to the old engine pan.

In tandem to our bracket iterations, were several attempts to connect the motor to the transmission. Our early versions were poorly aligned causing horrible vibrations that in turn produced noise. Noise was something we were trying to avoid by going electric. The final design paired two identical sprockets, connected inline by a #50 double roller chain. This seems to work quite well. It allows for small misalignments and produces the least amount of noise. There are of course many other options out there, and someday we may experiment with them. But, for now, this set up works for us. 

Take a look through our Electro-Beke playlist on Youtube  for video of the installation process. 

WIRING DIAGRAM

Including complete parts list..

Here it is. The schematic you’ve all been requesting. You may notice that it is drawn for a direct drive system, where the motor is used to electronically shift from forward to reverse. We have since installed our motor in front of our old transmission and no longer need the Fwd/Rev circuit. However, since the majority of set ups out there use the motor to achieve Fwd/Rev, we wanted to show our diagram depicting a similar set up. If you end up with a Series or PM motor, you should be able to modify this diagram by excluding the 12V bank to motor connections. However, many of the components, like the contactors, require a 12V supply to operate their solenoids. So you will still need a 12V accessory bank. This is often the house bank of a boat, since many smaller boats run 12V house banks anyway.

Below are the components we used, why we chose them, where to buy them and pictures of them installed in our boat. If you didn’t figure it out already, their letters correspond to the diagram above.

(A) – 10A FUSE 

Buy one HERE .

This is a simple automotive fuse held in an inline fuse holder. It protects the ignition circuit wiring from drawing too much amperage in the event of a short.

(B) – Key Switch

Buy one here . .

The key switch is mainly for security. It can be replaced by a simple on/off switch, but taking the key out will slow down someone trying to leave with your boat, without your permission.

(C) – FWD/REV Switch

This switch is only needed if you are planning a direct drive system. We no longer have need for it, but also have yet to rewire our system after we installed the transmission. It is a basic rocker switch with an on/off/on rocker and 6 pins on the back. This allows both positive and negative wires to be switched. We also wired ours so that it will shut off the contactors if switched accidentally while the throttle was engaged. That way it wouldn’t cause any damage to the motor.

(D) – Throttle

The throttle tells the motor controller how much power to send the motor. We chose this one because it allowed us to keep our existing throttle lever and cable mounted on the steering pedestal. It also has a micro switch that we use to close the secondary contactor (N) on the 48V side and the Fwd/Rev contactor (E) on the 12V side when the throttle is pushed forward. This ensures no voltage is going through the system until the throttle is actually engaged.

(E) – FWD/REV Contactor

This, again, is not needed if you, like us, install the motor with a transmission that handles Fwd/Rev. However, if you are planning a direct drive set up, and the controller you chose doesn’t have a Fwd/Rev circuit, then this is a necessary evil. The one we used, we scrapped off an dead windlass. It works great for the 12V circuit and are easy to find.

(F) – Main Battery Switch

Our boat came with this switch installed already. We simply rewired it slightly to accommodate our systems. For now we only use the “Battery 1” and “off” settings. However, if we eventually install a DC-DC converter to bring our 48V bank down to 12V we could wire it to the “battery 2” position as a back up battery bank.

(G) – Positive Buss Bar

Pretty basic here. A buss bar is used to connect multiple leads to the same source. This one is beefy to handle high amperage on the positive side of the 12V circuit.

(H) – Negative Buss Bar

Same as the Positive buss bar above. However this one is tied into the 48V circuit. 

(J & M) – Shunt

These are pretty standard. They are required to hook up an amp meter and measure how much amperage is running through your system. Often an amp meter will come with its own shunt. They sample the current so that not all 100+ amps are running through a meter. That would be very dangerous. Just make sure the shunt and meter are rated for the same mV, usually 50mV or 100mV.

(K & U) – Main Fuse

These fuses protect the wiring in the system. The closer to the battery bank the better. The fuse on the 48V side is rated for 200A and the 12V fuse is rated for 80A. These are rated for amperage only and can usually take a variety of voltages. Both fuses and holders are identical. They just have different ratings.

(L) – Primary Contactor 

This contactor is wired to the main key switch. It is a bit redundant but shuts off any power from the controller, motor and gauges. It acts more like a battery shut off.

(N) – Secondary Contactor

This contactor supplies the motor controller with the power it needs to run the motor. It is also the one that is bypassed by (T) the pre-charge resistor. Contactors are just big remote activated switches. Like breakers, they activate very fast to eliminate high amperage arching.

(P) – Motor Controller 

The motor controller we chose works for our application, but there are many out there to choose from. Do your own research here before deciding on what motor you will use. We happened to get a sweet deal on ours so we made it work with our motor. Our system would be less complicated if we used a controller designed for a SEPEX motor. The Curtis 1209B that we have is designed for a Series motor, but we make it work.

(Q) – DC Motor (SEPEX)

Sorry, you’ll have to find this one on your own.

Since another motor like ours has yet to show up again for sale online, we can’t really recommend the same one. However, the basic idea is finding a motor with the appropriate wattage to push your boat. Refer to our “Power Requirements” section to get an idea of what that might be. Then just make sure it will produce the desired power at a voltage that you would like to work with. We recommend 48V for most applications for reasons described previously.

(R) –  Amp Meter

These attach to the shunt (J & M) and show you how many amps are running through the system. Depending on where it is placed it can either read the amps being drawn from the battery bank or the amps going to the motor. We decided to read the amps being drawn from our batteries.

(S) – Volt Meter

This meter does not require a shunt. As long as the negative lead makes its way back to the negative buss bar, the positive lead can be attached at any point along the circuit. We chose again to read the battery bank voltage with ours. However, it can also be place on the motor to read the voltage there instead.

(T) – Pre-charge Resistor 

They look like THIS . 

There is no specific item to show you here. Each controller and each set up is different. But, I can tell you that the pre-charge resistor is very important. It by-passes the main contactors and supplies the motor controller with the power it needs to pre-charge, so its ready when the main contactor is switched on and all that amperage comes rushing in.

Make sure you check out SV Bianka’s page for another detailed blog about his electric motor installation.For another great article about all the other stuff that goes into a motor installation,

you might want to read “Balance of System” . The article is for an electric motorcycle set up, but the basics are similar enough.

One thing we learned very early on was that . . .

Volts (v) x amps (a) = watts (w) or v x a = w.

At first we thought (please don’t laugh we were total newbies)  that if we took 4 – 12V batteries with 125aH, and wired them in series, we would get a 48V bank with 500aH capacity. Obviously we forgot everything we learned in high school algebra. We soon resolved our mistake and learned that this formula is at the heart of everything electrical. As you can see, Watts are the thing you need to pay attention to. Remember high school physics? W=Work. Many appliances in your house, often things that produce heat, are rated in Watts, but marine stuff tends to rate things in Amps. Well, for our sake Watts are king. No matter what boat you have, it requires a certain amount of work (Watts) to push it through the water at any given speed. So, your job is to charge, store and supply to the motor a similar amount of wattage in order for your boat to move. The more watts you can store, the longer you can push your boat.

“The more watts you can store, the longer you can push your boat.”

As mentioned before, our motor is a SEPEX motor. This meant that the field and armature needed 2 separate voltages in order for the motor to spin. The way we solved this problem was with two separate battery banks. The field is powered by the house bank at 12V. This bank consists of two deep cycle batteries wired in parallel giving us about 250Ah at 12V. So far, it has held up great. It powers everything onboard including the inverter and laptops. We use about 30Ah on a slow day at anchor, and around 70Ah when sailing or when we’re both using our laptops all day at anchor. The nice part, is that even on a cloudy day, our 480W solar bank can replenish that before dinnertime. But we’ll talk more about that in the next section, “CHARGING” below. 

The motor bank consists of 4 – 12V deep cycle batteries wired in series giving us about 125Ah @ 48V. This may not seem like much, but in the last month of sailing, we have logged over 1000 miles, including sailing 25 miles up the Cape Fear River, and have never depleted the motor bank more than 35%. That works out to drawing only 44Ah used. We’ll talk more about range and testing below in the “TESTING” section. 

There are many types of lead acid batteries on the market. Don’t get too invested in brand. Most of the batteries on the market today are made by the same two companies. Trojan seems to be the brand of choice for many. We found batteries for sale locally and for $100 each, including delivery, we couldn’t pass them up. We also knew that the flooded lead acid bank we installed is only temporary. Like we’ve said before, this whole “Electro-Beke” thing is really one big experiment. We have plans to install a LiFePO4 bank soon enough. But we’ll tell you all about that in the “WHAT’S NEXT” section below.

There are many inefficiencies in electrical systems, like heat. However, don’t worry about them too much. If you budget 30% power redundancy into your system, it will more than cover any losses from heat, or mechanical friction and so on.

Check out www.batterystuff.com . They have useful calculators for battery banks and solar, along with great information on different types of batteries and what they are used for.

Our Solar System . . .

Also doesn’t include pluto..

We have 480 watts of solar. Broken down into 2 – 240W panels at 24v wired in series to give us a nominal voltage of 48V. Did you get all that? Great! Steven, from Solar EV Systems , gave us a great deal on them, landing him a spot in our Uma Angels Family . There are a several types of solar panels, but as far as we can tell, any modern panel is efficient and well made. None are much more efficient that others, it’s more about the size of your mounting space, and the size of your wallet. The ones we have are made by Trina, They are not expensive, look well made and perform exactly as promised.PV (Photovoltaic, aka solar panel) modules have three different voltage ratings that are handy to understand:

• The nominal voltage of a panel could also be called the “conversational voltage.” When we talk about the voltage of the panels and the other components of the system, we’ll most often use the nominal voltage. Nominal voltage actually refers to the voltage of the battery that the module is best suited to charge; the term is a “leftover” from the days when solar panels were used only to charge batteries. The actual voltage output of the panel changes as lighting and temperature conditions change, so there’s never one specific voltage at which the panel operates. Nominal voltage allows us, at a glance, to make sure the panel is compatible with a given system without having to look at the exact voltage. Our panels have a nominal voltage of 24V. We wired them in series which gives us 48V. It reality, they put out about 75V on a sunny day. But our charge controller allows us to charge a battery bank from 48V all the way down to 12V with the same solar panel set up. We’ll talk more about our charge controller later.
• The second voltage rating is the maximum power voltage (Vmp). This is the highest voltage the panel can produce while connected to a system and operating at peak efficiency. As mentioned above, the max our panels will produce is around 75V, even though we talk about them as a 48V panel system.
• The third voltage is open circuit voltage (Voc). This is the maximum voltage that the panel can produce when not connected to an electrical circuit or system. Voc can be measured with a meter directly contacting the panel’s terminals or the ends of its built-in cables.

Panels also have two different current ratings: current at maximum power (Imp) and short circuit current (Isc), both listed in Amps. The maximum power current is similar to Vmp: it’s the maximum current available when the panel is operating at peak efficiency in a circuit. Ours can produce 35Amps at max efficiency, They consistently produce 30A on a sunny day and we’ve seen as much as 32A. Similar to Voc, the short circuit current is the current measurement your meter would show when in contact with the positive and negative terminals of the panel while not connected to a system or load.All these voltage ratings and current ratings are often found on the back of a panel. Use them to estimate how much power they will be able to produce.

Two rules of thumb:

• 1kW or solar will produce 4kWh/day
• Rated Watts / 3 will get you approximate Ah/d @ 12V.

So, according to this, our 480W panels should give us 160aH on an average day, which we’ve found to be quit accurate. Although, we’ve only ever needed more that 100Ah of charge on one occasion. So usually, our batteries are charged back up before lunch, and we spend the rest of the day on “float” charge.

Types of Panels

Monocrystalline.

These are single silicon cells grown into larger crystals, then cross-section cut into small wafers to form individual cells that are later joined together to form a solar panel. This cell type has high conversion efficiency which means it takes up less space on deck. These cells are generally not shadow protected and are often more expensive per watt.

Multicrystalline (Polycrystalline)

These cells are also single silicon cells constructed by utilizing multiple amounts of smaller crystals to form a cell. This cell type has very high conversion efficiency but is also not shadow protected. Although, you should really be installing any panel so it doesn’t get blocked by shadows throughout the day. It will drastically increase the output if you install them in a proper location.

Amorphous silicon

These are the most inexpensive to manufacture. They are produced by depositing an active silicon material on various substrates like stainless steel sheet. The conversion efficiency is not as good as the single crystal type, but Uni-Solar panels are this type of panel and are shadow protected. Shadow protected means that a panel continues to charge when part of the cells are in a shadow, like a stay, which is a great advantage on a sailboat.

Our Charge Controller . . .

Is at the heart of it all..

The next, and possibly most important component in our charging circuit, is our Midnite Solar KID charge controller. This thing is amazing. Midnite also joined our Uma Angels Family when we asked them to send us a controller and they agreed. We spent a lot of time researching solar charge controllers and learning all about PWM vs MPPT. Bottom line is, if you can afford it, get the MPPT controller. We chose the Kid because it’s just the most efficient at collecting power from your panels. It is also easy to program and understand. We currently run it at 12V and just rewire our motor bank to 12V when we need to charge it. However, we will soon be adding a smaller, simple 12V charger to the “load” circuit of the Kid. This will allow the Kid to be permanently charging the 48V house bank. But, when it is full, switch over to the “load” circuit and charge our house bank through the smaller controller. It may all sound too complicated now, but once it’s installed and working, we’ll be sure to share everything with you in more detail. 

“We have never gone 24hrs without fully charged batteries.”

On a boat, where space is at a premium, you need all the efficiency you can get. Right now, I’m sitting on the boat, it is overcast and raining outside, it’s noon and we’re getting around 100W of power in from our panels (about 8-9A @ 12V). Our house bank will be charged back up by dinnertime, same as the last few days, and we haven’t seen the sun all week. When it is sunny, our house bank is usually charged back up before we wake up in the morning. No we don’t wake up THAT early, usually around 10am, but seriously, if it’s sunny in the morning, we put 30+aH into our batteries before 10am. The charge controller runs silently, however it makes a tiny click when it switches from “resting” to “BulkMPPT”. Since on a boat, we’re attuned to every tiny sound, we usually here it click on and off a few times before the sun even rises. Mind you, it’s only putting in 0.5aH then, but still, the sun isn’t even over the horizon yet and we’re already charging our batteries. 

Check out “Step 26” when we install our solar panels and charge controller. 

The rule of thumb we used when designing our system is that 1 – 100W panel can charge a single deep cycle battery from 50% discharged in a single sunny day. So we have 6 batteries, so ideally we would have 600W of solar. Now, that just wasn’t practical for us, so we settled for 480W and it keeps up just fine. However, if we discharged our motor and house bank down 80% we would need about two sunny days to get them both topped back up fully. Or, about 4 rainy days. For us, this isn’t an issue since we typically use the motor for very short periods of time right before anchoring or when setting off for a multi day passage. So, by the time we need them again, their both fully charged and ready to go. If not, we’ll just hang out and drink a beer. So far it’s never been an issue or even come close to it. We have never gone 24hrs without fully charged batteries.

Many have suggested we have a small generator on board as a back up, just incase there is no sun for many days and our batteries are dead. So far, we have gone a full week without sun and our solar has kept up just fine. Although, we may design a system with the ability to be hooked up to a genset for extending motoring, like say the Panama Canal, so that if we ever needed to, we could just set a generator on deck for a few days and then get rid of it as soon as we’re done. But, for now the whole point was to get away from petrol dependance. 

So far, solar is our only means of power production. We do have plans to get working regeneration from the prop while sailing. The possibility is definitely there, and we have tested for voltage while sailing. But as of today, we haven’t hooked up a charge controller to it. Mainly because we just don’t need it…yet. Our power requirements are so minimal and we use the motor so little, that we haven’t bothered to hook it up yet. But, it is on our short to-do list. So stay tuned for future updates. 

HERE is a link to a great forum talking about solar systems, battery banks and how to balance them. 

How far can you motor? 

Maybe the most asked question we receive..

It’s a valid question for sure, and one that many have asked us. But, we have yet to find out. We are still early on in our testing phase of the experiment. We’ve used the motor many times but rarely for more than 10-15 min and never more than 30. It is also hard to find “ideal conditions” to test in. There either isn’t enough space, time or light. Or the tide and wind aren’t in our favor. Sounds like excuses we know, but it’s the truth. 

“We are in no hurry to go anywhere,  ever.” 

From what we have done, we can tell you this. Our max speed has been right at 4kts. but it was against a slight current, maybe 1kt max. So, that would mean our theoretical top speed is closer to 5kts. 

Here again, we haven’t actually found out. Mostly because without a tow boat right beside us, it would be dangerous to run out of power in the middle of a channel or bay where there are “calm conditions”. But, we’ve motored for 2 nautical miles at 3kts (with a 1kt tide in our favor) and it drained our batteries down to 70%. So, that would mean that in “ideal conditions” we could motor at 2kts for 6 nautical miles. Doesn’t sound like much, we know. But, with a favorable tide and even a slight favorable wind, we can extend that tremendously. We also wait for the wind and tide to be favorable and then just sail to where ever we need to go.

With limited area to mount solar panels and without a genset, we knew if we used more power that we could generate, we would always have dead batteries. So, from the beginning, we focused more on how much power we could consistently generate, and base our system off of that. To us, the meant using less, not necessarily making more. Our solar has kept up great so far, but our power needs have also been minimal. We have autopilot and a chart plotter that are always on when sailing. We also use our laptops constantly and run a small inverter for tools and small cooking appliances like blenders. We have all LED lights too. We don’t have a refrigerator yet or windlass. But they are on the short list. We also have yet to capture any power from the prop while sailing. So there is still room to capture more power if we need it. 

As we continue to sail further and upgrade and modify our system, we will also continue to update you on how it all works here. So keep a look out for updates on our Facebook page and in future videos.  

WHAT’S NEXT

We may have a spinning Motor . . .

But the fun has just begun..

Well, our motor works. It pushes our boat reliably. The Electro-Beke experiment is a success, at least in our eyes. Now the real fun begins. We’ve proven to ourselves that we can sail further that we thought and use the motor less than we originally planned. So, what’s next?

“We have a few more project on the list of upgrades and modifications.”

We have a few more projects on the list of upgrades and modifications. The first thing on the list is to rewire our system and remove the redundant components left over from the direct drive phase. After that, installing some better gauges and monitoring systems would be really nice. There is a “fuel gauge ” we would like to install for the motor bank and house bank. It is simple and relatively smart. It will give us an accurate state of charge in a quick glance. 

Next on the list will be installing a charge controller or developing a similar system to allow us to capture power from the spinning prop while under sail. Technically our motor is capable of it, and early tests have augmented this theory. We are currently working with a few companies to figure out what the best system will be. 

We also need to install a larger heat sink for our motor controller. The one that came with it is designed for air movement across its fins and is therefore undersized for our needs. However, we may be upgrading to a true SEPEX motor controller before long, so it will handle regeneration and would require a different heat sink anyway. 

The big ticket item on the list is to install a large LiFePO4 battery bank. We have our eyes out for a salvaged Nissan Leaf or Chevy Volt that still has its battery bank intact. We’ve seen them for sale before and would love to get our hands on one. LiFePO4s are much more stable than other types of Lithium Ion batteries. But, we’ll talk about that if and when we actually get our hands on some. 

• What's My Car Worth?
• Buyer's Guide

Maserati Tridente Electric Speedboat Revealed, Just in Time for Summer

The Italian automaker casts off for summer by showing the upcoming Tridente, the perfect battery-electric tender for your luxury mega-yacht.

• Produced in partnership with EV marine company VitaPower, the Tridente features two electric motors that make a combined 600 horsepower and offer a cruising range of up to 43 miles.
• We've toured a prototype of the vessel, and it's as luxurious as you'd expect; orders are being accepted, with delivery to take around 10 months.

Imagine zooming to the coast in your Maserati for a day on the sea in a matching powerboat. That fantasy could become your reality, as the Italian automaker has shown a prototype of its new Tridente powerboat. And as if a boat joining the lineup wasn't enough of a twist, consider that the Tridente is entirely electric, making it part of an emerging electric boat segment.

Developed in conjunction with EV marine company VitaPower, the Tridente appears to be based on Vita's Lion powerboat concept but features upgrades that make it a true Maserati. There's a large touchscreen at the helm, seating for eight, and a sundeck bed and swim platform at the stern. The Tridente comes with four batteries, two on the starboard side and the other two on the port side.

The 34-foot speedboat has a sleek look, shown here painted in a matte rose gold finish and topped with a cream-colored interior. Under that paint are a carbon-fiber hull and two electric motors totaling 600 horsepower.

Maserati says that the Tridente is capable of a top speed of up to 40 knots and can cruise at 25 knots for up to around 43 miles (70 km) before needing to be recharged. Recharging, it's said, can happen via a DC connection, and the battery can be replenished in as little as an hour.

Intended to serve as a day boat or a tender for a larger yacht, the Tridente is claimed to have sufficient range to cross Lake Como or to cruise from points of interest along the coastline with none of the emissions or odor of a gas-powered engine. A sun canopy can provide shade during the day, and a small cabin is nestled ahead of the helm and features a small bed, a toilet, and a sink.

One thing the Tridente will not share with its automotive siblings is its seven-figure price. The Tridente is available for order now, with a starting price of $2,660,000 at current exchange rates, and delivery to take around 10 months.

Drew Dorian is a lifelong car enthusiast who has also held a wide variety of consumer-focused positions throughout his career, ranging from financial counselor to auto salesperson. He has dreamed of becoming a Car and Driver editor since he was 11 years old—a dream that was realized when he joined the staff in April 2016. He’s a born-and-raised Michigander and learned to drive on a 1988 Pontiac Grand Am. His automotive interests run the gamut from convertibles and camper vans to sports cars and luxury SUVs.      

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