sailboat wind generator

Better Sailing

Best Marine Wind Turbine Generators For Boats

Unless you are happy burning endless amounts of fuel, a marine wind turbine is an essential item fr an offshore cruising sailboat. In this article, we will be taking a look at some of the best wind generators for your boat.

Today’s cruisers carry so much electrical equipment that wind turbines, solar PV arrays, and hydro-generators are becoming more and more common. The marine wind turbine has been around for several decades now and has gradually been refined to give a much higher degree of efficiency. Better alternators, CAD-designed blades, life-sealed bearings, and smart charge controllers make the latest devices more reliable, quieter, and safer.

Things To Consider When Shopping For a Marine Wind Generator

Horizontal axis vs. vertical axis wind turbine.

The majority of marine wind turbines are horizontal axis devices, either upwind or downwind driven. These are powerful and, as such, need speed and/or charge output limiters, or they can burn out the batteries and self-destruct in storm-force winds. Vertical axis turbines are more suited to trickle charging – usually connected to one or two batteries up to 200Ah capacity. The blade design means they are unidirectional and thus have no need for a bulky tail fin to point them into the wind. They are also considerably quieter than most horizontal turbines and much easier to mount and install.

What Blade Design Should Your Wind Generator Have?

Modern turbines usually sport a one-piece, cast aluminum body and, commonly, three aerodynamically designed plastic/composite blades. One of the first of these models, the original Air-X, worked exceptionally well, particularly in high winds. However, it was so noisy that neighboring boats frequently complained, leaving the owner the option of turning it off or moving well away from other boats. Since then, CAD-inspired blade design has significantly helped to reduce ambient noise levels, although none could be termed silent.

Once your battery bank is fully charged, additional energy from the turbine needs to be dissipated, or the turbine stopped. Low power vertical-axis models don’t usually produce enough to warrant fitting a regulator, but the more powerful models all need some form of charge limiter to prevent overcharging. The simplest form of regulation is to switch it off when no further charge is needed. If you electrically disconnect the turbine, however, it can either damage the alternator diodes or carry on spinning at an even higher speed, so most are electrically ‘braked’ by shorting out their output wires, and a high-current switch is usually provided for this action.

If you leave a turbine running unattended, you’ll need an automatic regulator, and there are two systems commonly available. The first lets the turbine continue to spin and produce power, diverting any that isn’t needed into ‘dump’ resistors to burn off the excess as heat. While effective, it is pretty rudimentary, and you have to be careful where you mount the bulky resistors, which can get quite hot. Alternatively, some use this unwanted charge to pre-heat the hot water tank via an immersed element. Other turbines incorporate ‘pitch control’, comprising feathering blades that either flatten out or turn edge into the wind to regulate turning speed at high wind speeds.

Charge Controllers

A variety of automatic charge controllers are available, some more sophisticated than others, and you don’t necessarily need to use one from the same manufacturer unless it specifically states that you must. A basic model has a voltage-sensitive on/off switch that will trigger at a pre-set threshold battery voltage. The more useful controllers have a built-in display for monitoring turbine output and battery condition. Some can also accept and distribute charge from other sources, such as solar or hydro generation.

>>Also Read: Best Portable Boat Generators

Here Are Some Of The Best Best Marine Wind Turbine Generators For Sailboats

Auecoor solar wind hybrid system – best marine wind turbine generator on amazon.

The Auecoor Solar Wind Hybrid System is the best system to hook your boat/sailboat with. It is a hybrid system that utilizes both solar and wind power generation. This system is highly efficient, it is designed to withstand heavy wind loads, and it is ready to install on a boat/sailboat. They also produce many models to serve your needs, from 500 Watts all the way up to 2000 Watts in optimal weather conditions. 

All models come with a 400-Watt wind turbine generator, and then you can add as many 120-Watt high-conversion, waterproof and flexible solar panels as you need. This unit is also pretty easy to install. The solar panels are easy to transport, and they come with pre-drilled holes for easy installation. This is my personal favorite kind of setup and the one that I believe is the best for any serious boater. It provides 2 renewable sources of power that guarantee that whether you are making a passage or liveaboard in a nice beach somewhere, you will have dependable power as if you were living connected to the grid.

Air Breeze 200

Although the latest generation Air Breeze, made by Primus Windpower, provides an increased charge output, it is also quieter and should apparently outlast its predecessors. Its low start-up speed (4.2kn) means that, on average, it should be able to produce more energy than some higher-rated turbines over long periods of low-to-moderate wind speeds. Though it only has a maximum output of 200W, its output has been optimized to provide a more constant charge in typical northern European and Mediterranean wind conditions. The new Air Breeze weighs less than 6kg and has an integral electronic charge controller and over-speed regulator, rendering bulky dump resistors unnecessary and making installation considerably quicker and easier.

Leading Edge LE-300 or LE-450

A UK company, Leading Edge supplies wind turbines for both marine and terrestrial installation. The LE-300 and LE-450 are available in 12V, 24V, and 48V versions and are remarkably light, making them ideal for sailing yachts. The output is DC via two wires, and a run/stop switch is supplied that breaks the turbine by shorting the output. The units can also be supplied with charge controllers, a dump load style regulator that allows you to leave the turbine on 24/7 without the batteries overcharging. The three-bladed LE-300 is very light (6kg) and one of the quietest of the three-bladed models. However, its output is poor for a horizontal-axis turbine, although it starts spinning in the gentlest breeze. The five-bladed LE-450 is more powerful (105W at 15-knots) while remaining quiet and stable. Another great feature of this wind turbine is that it is the quietest marine wind generator tested.

Rutland 1200

The latest in the Rutland wind turbine line up, the 1200, is Marlec’s answer to the third generation three-blade, permanent magnet turbine models. More powerful than the 914i, it features a ‘Tri-namic’ blade design, which is said to provide a low start-up speed, very quiet running, and more power towards the top end of the wind scale. With a claimed peak production of 483W (that’s 35.5A at 12V) in 29 knots of wind, the 1200 can also supply a very useful 40W of power in just 10 knots of wind – a more realistic average in most waters.

The 1200’s charge controller has dual outputs for two separate battery banks and can accept up to a 20A solar PV supply. It reduces the turbine speed automatically after winds reach 30 knots, regulating the charge without using dump resistors. It also has an integral start/stop switch and can support a remote display, which connects to the controller via a simple Ethernet cable.

Eco-Worthy Wind Solar Power Kit

What can I say? I just love a good wind-solar hybrid power generator. With this kind of setup, you won’t have any problem charging a 12V or 24V battery bank with this hybrid system throughout the day, in any weather condition. The Eco-Worthy Wind Solar Power Hybrid generator can guarantee enough power for you to remain comfortable on your boat and operate any appliance you need and enjoy your time on the boat. You can purchase any model that fits our needs starting from 400 Watts all the way up to 1,400 Watts. However, always buy a generator that has a higher power output than you think you will need because you almost always won’t be in optimal climate conditions.

The blades on this German-built device are very steeply pitched towards the hub, resulting in an early start-up in lighter airs, and they also incorporate tiny fins along their length, said to quieten them at high speed. The blades have a kinetic rotor pitch control system designed to feather them in very high winds, not unlike the large terrestrial wind turbines. With a charge controller in the circuit, the turbine can therefore be left spinning in all weathers without worry. The output is two-wire 12V or 24V DC, so it could, in theory, be directly connected to a battery bank.

It can also be used with a simple short-circuit stop switch, which will slow it down enough to be tied off. The Superwind 350 can also be supplied with a 40A SCR Marine charge controller, which has two independent, diode-isolated outputs for start and service battery banks and dissipates unwanted energy via two large, wire-wound dump resistors. Nominal power is 350W at 25 knots.

Silentwind 400 Wind Generator

As fitted to all boats in the Volvo Ocean Race and featuring ‘Silent Power Blades’ – hand-laminated carbon blades, successfully tested at hurricane speeds – the latest Silentwind 400+ has improved wind tracking and earlier start-up than its predecessor, the 400. Featuring aerodynamics combined with a three-phase Neodymium-Iron-Boron permanent magnet generator, the 400+ is said to have a start-up speed of only 4.3 knots and a peak output of 420W at 30 percent less rotation speed than other 400W generators. 12V, 24V, and 48V models are available.

The Silentwind has a 3-wire AC output, which connects directly to the matching hybrid multi-stage charge controller that enables trickle charging and the connection of up to 20A of solar PV power. An adjustable boost function increases performance and optimizes the power yield, while the LCD displays all the important charge information. When the batteries are fully charged, the turbine automatically stops or switches to trickle charge mode with a significant reduction in rotation speed. It can also be stopped (braked) manually with the built-in switch on the controller.

Rutland 504 Wind Marine Generator

The Rutland 504 is a small and lightweight (just 3.5kg) mini-horizontal turbine from the UK off-grid power specialist, Marlec. The earlier model (503) has proven to be extremely popular over the years, in both the small leisure craft market and in commercial applications such as remote street lighting and signage, buoy lights, ATON power, etc., and the 504 should prove equally so. Like its predecessor, it is very compact, and its blades are ‘encapsulated’ – i.e., they have a protective ring around them to prevent limbs and clothing from getting caught up in the blades. Its output is better than that of the vertical-axis turbines but nowhere near the more powerful generators listed above. It is, however, notably quieter.

Typical output is around 15 knots of wind is 12W (1A @ 12V), doubling to 24W/2A at 20 knots. It also has a lower start-up speed than the vertical turbines and, although it takes around 10 knots of wind to provide any useful charge, its low-friction alternator compensates for the gusts by ‘smoothing out’ its output. The 504 does require a charge controller if it is to be left unattended.

 Leading Edge Vertical Wind Turbine

The LE-V50 and V150 vertical axis turbines are compact, lightweight, and virtually silent. The V50 measures 270mm dia x 456mm high and is intended for trickle-charging batteries or for running low-power devices. Available in 12V, 24V, or 48V versions, it has a nominal output of 12W but a peak of 70W. In typical waters, this results in an average charge of 0.5-1.0A @ 12Vdc in a fresh breeze. The bigger V150 model has a peak output of 200W but a more typical rating of 24W in wind speeds of 15 knots – double that of the V50. 

Leading Edge wind turbines were originally designed to generate power for industrial data monitoring equipment in very remote areas where there is no other power source; these often supplement solar PV arrays in an off-grid sailing situation.

>>Also Read: How to Charge a Sailboat Battery

Final Thoughts

There you have it; these are the best Best Marine Wind Turbine Generators for your boat or sailboat. Whether you are boating/sailing during your holidays or liveaboard full-time, a reliable power source is necessary. It will always provide you with the necessary power to operate your essential electronics, and depending on the power output you go for, it can fill up your batteries without an issue. Remember that when you are out in the water, it will be near impossible that there won’t be enough wind for a marine wind turbine to generate power, so you will rarely be without power. However, that’s why I always sail with both a wind generator and solar panels on board. 

Peter is the editor of Better Sailing. He has sailed for countless hours and has maintained his own boats and sailboats for years. After years of trial and error, he decided to start this website to share the knowledge.

Related Posts

The Ultimate Guide to Choosing the Best Fishing Line for Trolling

Lagoon Catamaran Review: Are Lagoon Catamarans Good?

Best Inboard Boat Engine Brands

Are O’Day Sailboats Good? A Closer Look at a Classic Brand

• Buyer's Guide
• Destinations
• Maintenance
• Sailing Info

Hit enter to search or ESC to close.

My Cruiser Life Magazine

Choosing a Wind Generator for a Sailboat – Complete GUIDE

Nothing denotes a salty off-the-grid ready yacht more than the sight of a wind generator mounted on the stern. Once, these were the main component of a sailor’s renewable energy arsenal. 

But today, as is the case with wind generators for RVs , the technology has fallen behind the fantastic strides that solar panels have made. Today’s solar panels are less expensive and more efficient than ever before, while wind generator technology hasn’t progressed much in the last 50 years.

Still, there are limited times when wind generators make the most sense on sailboats. Here’s a look at who could benefit from one and five of the best options on the market.

Table of Contents

Is a wind generator right for me, how much power do i need, alternatives to wind power, things to look for in a marine wind generator, 5 great marine wind generators.

Before you dive into the whirlwind of information out there about marine wind generators, take a step back for a reality check. Wind generators were the standard-bearer for years onboard sailboats, but in the 21st century, their usefulness has all but been replaced by solar panels. Solar is efficient, silent, and completely maintenance-free. 

As a result, the usefulness of a wind generator is now much more limited. There are many pros for wind generators—but most of them can be negated by one simple fact–the amount of usable power they produce is significantly less and more expensive than solar. 

Furthermore, the two times when a wind generator does make sense are not conditions typically encountered by most cruisers. Wind generators are only effective for significant power when the apparent wind speed on deck is more than 15 knots. That’s apparent wind speed on deck—meaning most downwind sailing in winds less than 22 knots true or so would be out. 

And then there are anchorages, where sailors hope that a wind generator will help them live off-the-grid to avoid a generator or engine recharge. How many anchorages have you recently sat in that had a constant 15 to 20 knots of undisturbed wind blowing through them? Most of the time, we’re trying to get out of conditions like that, not anchor in them. 

There are some parts of the world where these conditions are the norm. Caribbean trade winds and high latitude winds make wind generators more attractive. Those sailors stuck in the “horse latitudes” in between will find their wind generators silent and motionless most of the year. 

The other time that adding a wind generator makes sense is when there is simply no other renewable energy option available. A wind generator can mount in many ways on nearly any type of sailboat. It has a tiny footprint, unlike a large solar array. 

The bottom line is this—only add wind power when you have absolutely no space left for solar. If you’re maxed out on solar, a wind generator can give you a little boost. But another solar panel will consistently outperform a wind generator—unless you’re that rare sailor whose anchorages of choice feature steady and uninterrupted 20-25 knot winds.

Pros and Cons of Wind Power for Boats

• 24-hour per day operation (as long as it’s windy)
• Small installation footprint, compatible with most sailboats
• Good options when solar panels cannot be used due to mounting problems or shading (especially on ketches)
• Very low power generation in most conditions
• Ugly and bulky, mast and mount included
• Not effective when sailing downwind (like most tradewind sailing)
• Not effective in protected anchorages
• Maintenance intensive, moving parts and bearings wear out
• Limited controller options, many not compatible with LiFePO4 battery systems
• Expensive compared to solar

When calculating your requirements for off-the-grid living, the math does not lie. The problem is not lying when you do the math. You can find many calculators and spreadsheets online to help you make the basic calculations.

First, you need to know precisely how much power every electrical consumer on the boat will use and how long it will run each day. These items are often variable—refrigerators will have to run longer in hot climates and the summer, and lights will burn longer during the dark winter months. For everything that uses electricity, calculate the watts used per day (24-hour period).

Next, you’ll want to take into account how much power is being generated. It’s impossible to get accurate numbers for your setup until you’re out there doing it. In general, solar can be counted on for its maximum output for three or four hours a day. How many sunny days a year depends on your location. Again, there are many calculators online.

The wind is good for 24 hours a day, of course, but the wind is seldom that constant. So when calculating the math for a wind generator , it’s very easy to feel good about the choice. But practice has routinely shown that even a small solar array will outperform it in nearly every location.

As already mentioned, the number one choice for most sailboats for renewable power is solar. Solar panels are inexpensive and last for decades with zero maintenance. The downside is that they require a lot of shade-free space to work best.

For boats looking to make power during offshore passages, hydrogenerators are another solution. As long as the boat is cruising at six knots or more, the water passing by has enough potential energy to run electronics and charge batteries. The Watt & Sea Hydro generator is one of the best options out there, but there are also towable generators that do not require permanent installation. Some boats even have the option to use the free-spinning propulsion propeller to create electricity. Of course, these options only help charge the batteries when the boat is moving under sail, and only then at fast speeds. 

Power Output

The first thing to realize is that you must take manufacturer’s ratings for their units with a grain of salt. The numbers are engineering calculations for ideal conditions. That is to say, conditions that a marine wind generator will likely never get to experience. 

Of all of the performance numbers worth considering, perhaps the most interesting numbers are those at the low end on the scale – when does the unit start producing power, and how much. Most of us boat in places with 15 knots of wind or less most of the time, so this is the range your wind generator will sit in for most of its serviceable life.

Noise Level

First and foremost – do not be fooled by online reviews. Every wind generator on the market produces noise. Since the noise is generated from multiple sources, it can be hard to compare apples to apples when shopping for a generator. 

Blade design has a significant effect on noise – some blades are simply noisier than others. Not only does the blade’s aerodynamics make noise, but they can also cause vibrations. All wind generators will require occasional rebalancing and adjustment to minimize vibrations from the blades. 

The moving parts inside the generator can also cause noise. Most are mounted with standard ball bearings that can and do go bad. Many manufacturers advertise these as maintenance-free, but that’s simply unrealistic in the marine environment.

Finally, the mount on the boat is a significant source of noise because it transmits the blade’s vibrations, no matter how minor, into the boat’s structure. Proper mounts have rubber dampening pads built-in, but even still, some noise will get through. This can sound like a buzz, hum, or even a thumping noise.

Quality of construction plays a huge part in how much noise a wind generator makes. As a result, you get what you pay for with wind generators. Unfortunately, the inexpensive hardware store models built for residential use are typically the noisiest. 

You can compare the noise output of various wind generators by taking a stroll around the marina docks or a dinghy ride around the anchorage. Bad or poorly-maintained wind generators can be heard from many boat lengths distance. On the other hand, a high-quality unit will be difficult to hear when you’re standing under it, much less on another vessel.

Correct Voltage

Wind generators should be matched to your primary battery bank—the one that you’ll be charging. Most boats will be 12 volts, and a few will be 24. 48-volt systems are becoming more popular on electric yachts and those using the battery bank for big consumers like air conditioning. These are the exceptions to the rule, however. 

Charge Controller Functions

Unlike solar, wind generators are typically matched to the charge controller that the manufacturer packages with the unit. There are simply a lot more factors that go into regulating a wind generator, including the generation technology it uses and how it brakes or diverts its load. 

Charge controllers are either PWM (pulse width modulation) or MPPT (maximum power point tracking). PWM is a less expensive technology, while MPPT controllers are more expensive. In the world of wind generators, which one a controller features is a bit of a toss-up. Some manufacturers swear by MPPT, while others say there is no benefit to the added cost. 

Most solar chargers accept a solar input, usually only about 100 watts, though. It’s probably more efficient to run your solar array on its own MPPT charge controller. But if you’re only planning on installing a small array and don’t want the hassle of programming separate charge controllers, having the option with your wind controller is a very nice feature. 

Finally, the programmability of the charge controller is a significant factor. Very few of the older PWM charge controllers allow you to input charging profiles. Again, this is less of a problem with wind power than with solar. But if you’re planning to use less forgiving battery chemistries like lithium, you’ll want as much control as you can get from your controller. 

Brake and Automatic Cut-Off

Being able to cut a wind generator off in an over-power or over-speed scenario is extremely important. All wind generators come with some form of braking system. The brake needs to be used when the system reaches a full charge, or the wind speed goes beyond the wind generator’s limits. 

Remember that the generator’s not simply limited by what the blades and bearings can handle. There is also the strength of its mounts to consider. For example, a 60-knot gust on a free-spinning generator will impose an unbelievable force on its mounts.

Then there are wiring considerations. The wind generator is only designed to output so much power, and during your installation, you must use wire sized for the maximum output. What happens if more than that amount of current goes through wires due to a brake failure? Heat and possible battery damage will result, but hopefully, the circuit breaker or fuse will cut it off before then. 

Some have aerodynamic brakes that turn the generator as wind speed increases. This theoretically means that it can never go over its designed limits.

Others feature a brake that is automatically or manually activated. It’s designed to come on when the current reaches a maximum, such as during powerful wind gusts. It also breaks the unit to a stop when the batteries are fully charged. 

An alternative plan is to have a diversionary load. Some wind generators will come with dump loads, which are nothing more than ceramic heating elements. When the wind generator produces too much power, power is redirected from the batteries into these heating elements. They’re also used when the generator produces too much power for the system during storms. 

Mounting and Unit Weight

The mounting mast used to secure the wind generator is sometimes more complicated than the wind generator itself. It must be strong and stayed from all angles. Stainless tubes with two supports are commonly used to mount them to the back of yachts. 

The construction and position of the wind generator are essential to reduce vibrations and noise within the boat. Don’t mount a wind generator over someone’s bunk! All proper mounts have sound-deadening materials like rubber grommets built in to make them as quiet as possible.

The blades of a wind generator must be positioned so that they can’t catch any lines, canvas, or flags from other parts of the boat. This makes stern-rail mounting almost impossible on ketches and yawls. On these boats, mizzen mast mounts are often the best alternative. 

Keep in mind as well that the spinning blades of a wind turbine are like spinning knives. Sailors have lost fingers trying to secure wind generators during storms. Therefore, they should be mounted high enough that it is impossible to accidentally come in contact with the blades during normal operations. 

As mentioned before, another critical component of the mounting is calculating the correct wire size. This is calculated from the unit’s maximum output, the round-trip length of the wire run, and the unit’s charge voltage.

Finally, the positioning of the wind generator should supply it with uninterrupted airflow. If the wind is blocked, even slightly, but a mast, sail pack, or hardtop, the wind generator’s efficiency will be negatively affected. These items could also induce turbulence into the air being supplied to the turbine, which could result in vibrations and noisy operation.

When shopping around for wind generators , notice that power output is not one of our main criteria. This might seem odd, but all of the wind generators on this list produce more or less the same amount of power in a given wind. Some start producing at lower speeds, and some keep producing at high speeds, but in general, these occurrences are so minor and so rare that they don’t calculate into the shopping process.

Eclectic Energy D400

The D400 has a legendary reputation among cruising sailors as the wind generator of choice. It is nearly silent to the point of being very difficult to hear. It is built by Eclectic Energy in the UK, and you can spot its distinctive shape and five-blade design on yachts worldwide. 

For all the pluses, there are some detractors from the D400. For one, it is pretty much the most expensive option. It is also the heaviest—it requires a much beefier mount than other options do. 

SilentWind Pro

The SilentWind has a few advantages over many other wind generators. For one thing, the included MPPT charge controller features Bluetooth programming via a smartphone or tablet. In addition, you can set many parameters for the charge profile—meaning that it is one of the few wind generators that are at least somewhat compatible with the next generation of lithium marine battery systems. 

Compared to the D400, the SilentWind has a more lightweight and compact body. It’s a three-blade design that features blue composite fiber blades. The SilentWind is made in Portugal. 

Rutland 1200

Rutland is the wind power branch of the Marlec renewable power company from the UK. Rutland makes a wind range of wind generators for yachts of all sizes. The 1200 is a three-blade generator that features an MPPT controller with a solar input. At 10 knots of wind, it produces about 40 watts of power. 

Primus Air Silent X

Primus makes a variety of wind generators from their facility in Colorado. The “top-of-the-line,” so to speak, is the Air Silent X. It’s an upgraded version of their Air X that comes supplied with quieter blades made of distinctive blue carbon fiber.

Superwind 350

The German-made Superwind has a unique overspeed and overcharge protection system—the units feature feathering blades. This is undeniably more complex than many other options on the market. These generators are designed to be installed in grueling conditions where a damaged generator cannot be repaired quickly. Their primary market is aimed at remote telecommunication equipment stations and offshore sailors.

Matt has been boating around Florida for over 25 years in everything from small powerboats to large cruising catamarans. He currently lives aboard a 38-foot Cabo Rico sailboat with his wife Lucy and adventure dog Chelsea. Together, they cruise between winters in The Bahamas and summers in the Chesapeake Bay.

• Gift Certificate
• --> Login or Sign Up

Shop by Category

• All LED Replacement Bulbs
• BA15S/BA15D Bayonets (1141/1142/1156)
• BAY15D Indexed Bayonet (1157)
• BA9S Miniature Bayonet
• Edison - Screw-Type
• Festoon (SV8.5)
• Fluorescent Style
• MR11 & MR16
• PAR 36 Sealed-Beams
• Socket Adapters
• Boat Specific LEDs
• All LED Fixtures
• Interior LED Fixtures
• Exterior LED Fixtures
• All Navigation Lights
• Nav Lights By Function
• Economy Series LED Navigation Lights
• USCG Certified Navigation Lights
• LED Retrofit Bulbs for Nav Lights
• Portable LEDs & Flashlights
• All Cruising Necessities
• Comfortable Cruising Accessories
• Wireless Headset Communicators
• Chemicals and Compounds
• All Marine Wind Generators
• MarineKinetix MK4+ Wind Generator
• Wind Generator Installation Accessories
• Spare & Replacement Parts
• Marine Energy Products
• All Wiring & Electrical
• Marine Wire & Accessories
• Power Supplies & Voltage Converters
• LED Dimmers & Switches
• Wireless Remote Controls
• Dusk-to-Dawn Photocells
• 12VDC Device Chargers
• All Cristec / Scheiber OEM
• Cristec Products
• Scheiber Products
• Mantus Anchors

Shop by Brand

• MarineKinetix
• Cruising Solutions
• Sirius Signal
• View all Brands
• Marine Wind Generators

MarineKinetix MK4+ Marine Wind Generator

Bulk discount rates

Below are the available bulk discount rates for each individual item when you purchase a certain amount

• Buy 2 or above and get $75.00 off
• Create New Wish List
• Similar Products

Product Description

The marine industry’s highest rated wind generator.

MarineKinetix MK4+Wind Generator, including Controller - For Lead Acid, AGM, Gel and Lithium Batteries. 

The marine wind generator with a 100% satisfaction guarantee, and the industry's best 3-year limited warranty.   

Double click on the large picture above to scroll through scores of pictures of fellow bluewater cruisers worldwide relying on power from their MarineKinetix wind generator.  See a recent blog from a seasoned bluewater cruiser and Salty Dawg Rally organizer who solved his large energy demands using a combination green energy, including an MK4+ wind generator  here .

The MarineKinetix Wind Turbine has become one of the most popular marine wind generators available due to its advanced technology, superior output, and  super-quiet design.  The MarineKinetix is now considered to be the benchmark among serious cruisers. With a 30% to 50% larger swept area than the most popular marine wind generators, it is simply capable of intercepting more of the available windstream, and capturing more power.  Its sophisticated charge controller displays all the data, including Amps, Watts and Volts, and assures that the power makes it safely and efficiently into your battery bank through a 2-stage smart charging process. No need to buy extra meters , rectifiers, stop switches, or load diverters.  These are integrated into our smart controller. Just add your mounting pole and the wiring to your batteries, and you are ready to start producing green energy.

We are celebrating our 10th year of serial production, and our 6th year producing our latest design, the MK4+ Marine Wind Generator. The MK4+ replaced the popular MarineKinetix MK450.   

The MK4+ includes the following upgrades:

• The Wind Generator body is smaller and even lighter than the original design.  This is accomplished with a shorter, but more upright tail, with a greater surface area, and lower polar moment, for faster, and truer wind-tracking.  This lowers yaw error and improves performance in shifting winds.
• Upgraded asymmetrical pole-shifted rotor with 12 (vs 10) neodymium rare-earth magnets for more power and zero cogging.  Bread-loaf magnet design for optimum air gap.
• Upgraded 36-slot stator with premium heavy-gauge copper windings.
• A new and improved anti-corrosion marine grade finish, which starts with a new high-pressure die-cast magnalium body, which is DACROMET pre-treated, then coated with a high-quality corrosion-resistant thermoset marine powder coating. No other marine wind generator uses this anti-corrosion process.
• New double yaw bearings.  Double bearings provide a larger "wheelbase" for the yaw joint, which reduces any free play, which can contribute to vibration and noise.
• Improved silicone o-rings which are totally weather-proof.
• Improved Aero'coustic 20% carbon-fiber filled injection molded blades, which are 18% more rigid than the previous design.
• All new Hybrid Wind/Solar Charge Controller with LCD display - with integrated battery monitor, stop switch, ammeter and watt meter. (no need for expensive monitoring panels).
• Patented 2-Stage PWM Charge Controller - Increases the efficiency of the charge cycle and tops up the batteries quicker and more fully.
• Improved high-precision hub, with tighter blade fastening tolerances, for perfect blade alignment and whisper-quiet operation.
• Improved molded urethane isolator pad, which fits between the pole and the collar.  Molded in "cap" allows it to stay put during assembly.

The great performance of the original MK450 remains.  The above changes are incremental improvements designed to improve start-up speed, ease assembly, resist corrosion, and improve real-world output. The MK4+ is truly a world-class micro wind generator.

Tired of talking to non-technical vendors that don't understand the nuts-and-bolts of what they are selling?  Give our technical rep, Jeff, a call directly at (864) 275-7837 to answer any questions. Read on to see what really matters when considering wind power for your boat.

Why Consider the MarineKinetix Wind System?

The MarineKinetix Wind Turbine System is simply one of the best performing small wind generator system available for marine use. That is quite a boast, considering all the small turbines out there with catchy names, and bigger advertising budgets, but read on to find out why we believe you'll soon agree.  

The MarineKinetix MK4+ is a simple to install, hands-off, super-quiet wind-energy production system made especially for the marine environment. This high-output, low start-up-speed system utilizes the best of European wind-science in its design. In addition to its leading-edge high-output dual-bearing 3-phase permanent magnet generator, it also features world-class aerodynamic efficiency with its carbon-filled aero'coustic rotor blades, which have been optimized for high torque, low rotational inertia, and exceptionally quiet output. These features, coupled with the included "hands-off" microprocessor-based charge-controller, and its exceptionally low yaw-error, make for what we think is the best marine wind generator system on the market. See why below.

The MarineKinetix MK4+ wind turbine system is a leap forward in wind turbine science. It makes the intelligent compromise between low-speed start-up and high-speed output, all at a realistic and cost-effective price.

• A complete 400 Watt Wind System (includes generator and controller)
• 1330mm Blade Diameter (1.3M) - Swept Area = 1.39 Meter
• Weighs only 17 lbs., about HALF the weight of certain competitive designs, without compromising performance thanks to a magnalium body, an asymmetrical rotor, and high-energy-density Nd2Fe14B rare-earth magnets 
• Lightweight 300g 20% Carbon Fiber Polymer Composite blades
• Available in 12V, 24V and 48V designs
• Compatible with VRLA, Gel, AGM, Lithium, and Lithium Iron Phosphate (LiFePO4)
• Industry Standard Mounting - Mounts to 1.5" Schedule 40 pipe (1,9"OD), or 48-50mm OD tubing
• Double marine thermoset powder-coat finish, over a DACROMET self-healing aluminum-zinc nano coat
• 5.8 knot start-up speed (begins producing power), 6.7 knot cut-in speed (begins charging 12V/24V batteries)
• Aero'coustic 20% Carbon Polymer Blades
• Super-silent - LAeq 35dB at 5M at 10 knots (about the same as a running fridge)
• Direct drive, 3-Phase dual-bearing AC permanent magnet synchronous generator
• Neodymium Iron Boron (Nd2Fe14B) permanent magnet synchronous design
• 12 pole rotor, with bread-loaf magnet profile, and asymmetrical pole-shifted magnet placement, for low cogging torque
• Automatic back-EMF braking at full charge (or 40 knots overspeed protection)
• IU PWM Charge Control Profile with hysteresis braking
• Microprocessor controlled auto set-point for AGM, Gel, VRLA, Flooded,  Lithium, and Lithium Iron Phosphate (LiFePO4)
• Requires no diode packs, diverters or external resistive loads
• Over-charge, over-current, and automatic over-speed protection
• Integrated heavy-duty yaw-axis slip-ring, allowing continued >360° limitless rotation
• Simple installation, and user-serviceable components
• Includes micro-processor charge controller with "at-a-glance" LCD charge, voltage, amperage and wattage status
• Fully compatible with existing solar installations (no conflict with other existing charging sources)
• 3-year limited warranty, and 30-day 100% satisfaction guarantee
• Full lifetime tech support by phone or email with purchase

What is included in the Wind Generator kit?

• MK4+ Wind Generator
• Smart Charge Controller with integrated performance monitor and stop switch
• Blades (x3) with SS blade mounting hardware
• Hub, with mounting nut 
• Snap-on molded plastic nose cone
• SS Hardware to mount clamping collar to your pole
• Silicone rubber isolator (goes between pole and collar)
• Assembly allen key tools
• Instructions

What accessories are available from Marinebeam?

• 50A Resettable Circuit Breaker
• Pole Mounting Hardware Kit
• 3-Piece Pole Mast 
• 10/3 Marine Cable
• Spare Parts

Details About the Unique Marine Kinetix Technology:

Our solution is a systems-approach to wind-energy production on-board. The MK4+ system couples several forward-thinking ideas into one "wind-system" which is easy to install, affordable, and maximizes energy production.  We did this by first starting with a low-friction, high-energy-density 3-phase rare-earth magnet rotor design, which came from concepts and materials used in leading-edge green-energy vehicle research. The Neodymium Iron Boron (Nd2Fe14B) permanent magnet rotor uses patented technology licensed from Sumitomo/Hitachi in Japan.  This is the same type of PM rotor design used in the AC synchronous motors in the Chevy Volt and other electric vehicles.   The rare-earth magnetic rotor is a key to its performance and low noise and vibration.  We now utilize an asymmetrical pole-shifted rotor design, which is a advanced method that replaces the heavy mass and cost of older skewed rotor designs, while providing the same advantage of reducing the cogging torque, and improving low speed performance.  We coupled this super-efficient machine with a biomimicry-inspired carbon-fiber-filled blade set, which makes for super-quiet performance while improving overall aerodynamic power.

The results are a turbine that outperforms others in start-up speed, output, and noise.  While other systems are idle, the MK4+ is generating. While other systems are disturbing the peace, the MK4+ is virtually silent. While other systems are struggling to charge, the MK4+ is topping off.

What are the important factors in wind energy production?

Physics dictates the basic performance of all wind generators.  In fact, the power available to any wind generator is a function of the square of the diameter (swept area of the blades) and the cube of the wind speed.  The ability of any specific wind generator to the capture wind efficiently depends on the length of its blades (its swept area) and its Tip Speed Ratio.   Tip Speed Ratio refers to the speed of the tips relative to the speed of the wind.  If the blades spin too fast relative to the wind, they begin to begin to look like a solid disk to the wind, and air piling up in front of the blades effectively blocks the wind behind it.  On the other hand, if the blades spin too slowly, much of the wind passes through the gaps between the blades, and the energy is lost forever.  So, swept area and blade design are the most important areas which the wind generator manufacturer can control.  While the MK4+'s blades are only 8 to 9 inches longer than the typical blade, they sweep as much as 40% more area than the competition.   With a nearly perfect tip speed ratio due to the computer-modeled and simulated blade design, and the impedance load-source matching of the controller, the MK4+ has a higher energy capture compared to most other designs. 

Because of the cube relationship of wind speed to power production, wind speed is absolutely the most important factor in wind energy .  There is no getting around the physics of that.  There is 27 times more power in a 15 knot wind than a 5 knot wind.  The key takeaway here is that regardless of the technology, you need good wind to get good performance from a wind generator .

What affects the ability to maximize output power capture shown above?

Wind generator power is dependent on wind speed, battery acceptance rate, and applied load , so a variable load and a discharged battery was used to characterize the absolute capture power for the data above.  As the wind increases, your wind generator will already be charging full-time, and the battery bank's acceptance-rate, in amps, will decrease as the battery charges and its voltage increases.  So, it is important to understand that by the time the wind is blowing 20 knots or more it is likely your batteries will not be capable of accepting the full amount of amps that any generator can provide.  This is good.  It means that your batteries are reaching a full state-of-charge, and that you have the headroom in power to cover any other loads as they arrive, without further discharging your batteries.  At the end of the day, it is best to think of a wind generator as a free-energy variable power source, whose output changes day-to-day depending on the available wind and the presence (or absence) of downstream electrical loads that it requires to generate power.

Read the following pages to learn about the MK4+, and view the video below to see how it performs against a much more expensive wind generator at very low wind speeds.

Our Integrated "Wind-System": Many popular marine wind generators are essentially sold in kit form, with the user left to decide what method of control they need to get the power into their batteries effectively.  Alternatively, some turbines have an included charging set-up, but offer what is essentially a simple automotive voltage regulator and a load diverter.  This can be a real problem for those wanting to optimize charging and protect their expensive batteries.  It is not enough to just generate efficient and effective power at the generator head. It is just as important to get that power effectively into our battery bank, and to regulate that power based on the battery's specific demands for voltage and current throughout its charging cycle.  By use of an IU charging profile, the system not only can be more efficient, but can also significantly prolong the life of the batteries by preventing overcharging.  Typical load diverter type controllers can only charge your battery to about 80% State-of-Charge (SOC).  This partial cycling is particularly bad for your batteries. Combining the Low Start-Up Speed "Tortoise Approach" with the High-Power "Hare Approach": Having seen both real-world performance in various anchorages around the world, as well as published performance testing over the years, we realized that the best approach out there on the "real water" was to apply leading-edge technology to each component of the system to find an intelligent compromise between the Tortoise Approach and the Hare Approach to wind energy production. A small wind-system that is capable of making power in low wind speeds can take advantage of a long day with low wind speeds by putting small amounts of power into the battery consistently throughout the day and night (the Tortoise Approach). On the other hand, a larger system can take advantage of big gusts or heavy wind by making tons of power very quickly (the Hare Approach).  The perfect solution for us cruisers would be a two-stage turbine that could be the Tortoise in low wind speeds, or protected anchorages, and could be the Hare in a high-velocity wind environment.   By leveraging leading-edge technologies to make incremental efficiency improvements in each of the discrete components of the wind system, we achieved a "sum of the parts" that meets our goals for an ideal marine wind system in-board.   We believe it is the best marine wind generator on the market for those sailors wanting a high-quality, hands-off, high-output, and super-quiet system.  Our real world data and feedback from our customers backs up that claim.  Read on to see how we did it. The Blade Set: We have found that the practical key to consistent production on-board is to start with a large 1.39 meter swept area, and then to apply leading-edge technology to the blade set to extract the maximum amount of energy.  Swept area is the most critical aspect of energy capture, and the bigger the swept area, the more power, period.  Blade length defines the swept area (Area= π r 2 ), and typically the longer the blades, the stronger and heavier they must be to withstand the exponential increase in torque.  The MK4+ solves this issue by using a unique 20% carbon fiber molded blade that is not only long and rigid, but extremely light as well (<300g).   This allows us to produce a blade that is up to 9" longer than the competition, but it weighs much less, and sweeps up to 40% more area. 

We also focused on the airfoils to get a super-efficient, super-quiet, Aero'coustic blade that gives exceptional power while maintaining low-speed start-up capability.  This way the turbine can take advantage of all-day energy production, but also can generate more serious power when the winds pick up.  It doesn't do much good to have great potential generating capacity if the blades never turn in the real world.  Compare our start-up and output to the competition, and you will see the distinct advantage. Details of the Design: The blade and tail design focuses on several key strategies:

• Low Start-up Speeds
• Very Low Rotational Inertia
• Very Low Noise at Optimum Tip Speeds
• Very Low Yaw Error
• Optimized Tip-Speed Ratio (the ratio of the speed of the tips to the speed of the wind)

While our carbon-fiber reinforced blade set has an extremely low rotational inertia, a strong and lightweight blade is only part of the story.  The starting torque on a wind turbine is generated in the blade area closest to the hub, while the power producing torque is produced in the blade area closer to the tips.  By use of German-engineered computer modeling and simulation, a variable blade profile was produced that can react quickly in low wind speeds, yet produce high torque and optimal tip-speed ratios at high speeds.  The blades are produced in a solid-model-patterned single-cavity injection-molding tool, so that each blade is identical in weight and profile.  Using a 20% carbon-fiber filled polymer makes the blade very light, durable, and repeatable. Lightweight blades have a low rotational inertia, which is critical in wind-energy production in the real world. Low rotational inertia allows the blades to accelerate more quickly, which means they can spin faster in lower wind speeds, therefore keeping the tip-speed-ratio (the speed of the tips vs. the speed of the wind) more constant.  Operating closer to the optimum tip-speed-ratio during gusts also allows the turbine to improve energy capture from these sudden gusts as well. Another way to increase aerodynamic efficiency --and to reduce noise on an airfoil blade-- is to manipulate and control the lateral airflow over the foil.  Of course, some of the best engineering solutions often come from mimicking what is already found in nature. Whales and certain fish have amazing hydrodynamic efficiency and stealth through the use of tubercles , or raised and slotted sections on the leading edges of their fins.  Our blades likewise use biomimicry-inspired riblets along the leading edge of the blades, which help the airfoil to create more power at lower speeds, and to operate more efficiently in turbulent air streams.   These Aero'coustic riblets, also prevent the air from traveling down the blade edge and "vortexing" off the blade tip contributing to tip noise. The noise you hear from most wind turbines is the sound of wasted energy. How quiet is it... really ? The MK4+ is extremely quiet, and we have never heard one quieter.  In fact, it measures only 35dB at 5 meters in 10 knots of wind.   At 15 knots, just a flutter, but no tip noise.  As the wind builds the flutter noise will increase.  Above 30 knots, everything exposed to the wind at that velocity will generate some noise, including the MK4+.  To get an idea of how quiet it really is, just watch the video below.  Note that the video was shot with a CMOS rolling-shutter camera, so the blades appear to be turning slowly, while in actual fact they are turning at several hundred RPM.  Video compliments of customer Hayden Cochran on his Island Packet "Island Spirit":

What is Yaw Error, and why is it so important?

This is quite different from most of the other, and more expensive, 400W generators.  The typical marine wind generator charge controller uses 50 year-old technology, which is simply a load-diverter switch, which, upon reaching a set-point, diverts 100% of the energy to a set of resistive elements (essentially heater coils).   So, when the battery reaches its dumpload set-point it isn't actually fully-charged, and this type of Partial State of Charge (PSOC) cycling damages the battery by reducing its capacity, and sulfating the battery plates.  They can't fully-charge the battery because they have no way to dump only the excess power produced, while continuing to top up the battery.  They can only dump all of it. The best scenario would be to have a way to progressively dump power so that the batteries could be fed with only the power that they need at this final stage of the charging process.   

 The controller is very compact (5-5/8" H x 5-7/8" W x 3-1/4" D), fanless, and is designed to be bulkhead mounted.  

It has the following additional features:

(1) Full monitoring capability (Volts, Watts, Amps), no additional battery monitors, shunts, panels, or displays needed (2) Backlit LCD display with clear graphical readout (3) Manual Brake deployment via keypad, so no additional stop switch is required (4) Battery charge level indicator (5) External load control (for managing lighting, etc)

Unlike some other popular marine wind generators which have internal controllers, there are no on-board electronics in the hot and salty elements, and there is no need for additional rectifiers, heat sinks, stop-switches, large resistive loads, or ammeters.  It all happens automatically and safely within the charge controller. It even protects from over-charging and under-charging. It is truly a hands-off charging solution.

Maintenance and Warranty: The MK4+ is designed to provide years of trouble-free service out in the elements, and has a 3-year warranty against defects in materials or workmanship.  We specified a simple and rugged mechanical set that uses very few parts, is easy to maintain, and will stand up to the rigors of the marine environment.  Unlike most single bearing automotive alternator-based designs, our dual low-friction rotor is supported by two low-friction bearings to provide long-life and easy start-up.  The unit is easy to disassemble, understand, and maintain.  The body is made of a lightweight magnesium and aluminum alloy, which is pre-treated with a zinc-aluminum nano-coat, and then a double marine-grade  epoxy powdercoat to resist oxidation and corrosion.   The MK4+ is bluewater tested by full-time cruisers, and like all of the Marinebeam products it is backed by the best technical support and warranty in the business.  Be sure to look at the various customer installation picture above to see some of our installations around the globe.

Interesting Links

Click here for our Frequently Asked Questions (FAQs) document.

Link to download PDF copy of installation manual  (V2.2)

Link to download PDF copy of controller manual  (V2.1)

Should you have further questions, feel free to contact us by phone or email.  Jeff, our resident MK4+ technician can be reached M-F 9-6PM at (864) 275-7837.  Or you can reach him by email at [email protected]

Product Videos

Custom field, product reviews, write a review.

18 Reviews Hide Reviews Show Reviews

Marinekinetix mk4 wind generator - highly recommended.

Posted by David Pollock on 28th Jan 2024

I’ve had my MarineKinetix MK4 Wind Generator for over 10 years and it has performed flawlessly! It is an exceptional product! Produces great power and is super quiet. While I also have solar, in the winter down in the Keys or further south, the daylight hours are reduced. But there is usually a 10+ knot wind. Nothing like waking up in the morning with the batteries fully charged. And quiet - I have had guests on my boat in a mooring field comment on the noise of wind generators on other boats. The MK4 is whisper-quiet, built solid with quality materials and they provide great service! Highly recommended!

Posted by Bob Golembicki on 12th Jun 2023

I replaced our very old two bladed Four Wind mizzen mounted generator this past winter with an MK4+ and are very happy with the output and how quiet and well balanced the new generator is as we’ve been sailing around the Chesapeake Bay this year. We’re running the engine to charge only on very calm days and maybe half as much as we had to with our old generator.

Posted by George Cline on 17th Feb 2023

Love my new wind gen. It’s quiet. Build quality is top notch. Installation is simple. Much happier with it than my previous wind gen from another brand.

Awesome product

Posted by Bob Osborn SV Pandora on 9th Dec 2022

After spending time with fellow Cruisers that had this unit on their boats, I had one installed this year. I had a wind generator years ago that we noisy and didn't put out much power. This one is as good as advertised. Quiet and powerful. I wrote a blog post about our power generating efforts aboard Pandora. Check it out. http://www.sailpandora.com/?p=12803

Recommended

sku: WR-10-3G

Round profile 10/3 marine tinned cable.

sku: CB-50A-42

50 amp manual reset circuit breaker.

sku: MK4-MOUNT

Marine wind generator mounting pole hardware kit.

sku: BL-MK-4+

Replacement blade for marinekinetix mk450 or mk4+ wind generator.

• New Sailboats
• Sailboats 21-30ft
• Sailboats 31-35ft
• Sailboats 36-40ft
• Sailboats Over 40ft
• Sailboats Under 21feet
• used_sailboats
• Apps and Computer Programs
• Communications
• Fishfinders
• Handheld Electronics
• Plotters MFDS Rradar
• Wind, Speed & Depth Instruments
• Anchoring Mooring
• Running Rigging
• Sails Canvas
• Standing Rigging
• Diesel Engines
• Off Grid Energy
• Cleaning Waxing
• DIY Projects
• Repair, Tools & Materials
• Spare Parts
• Tools & Gadgets
• Cabin Comfort
• Ventilation
• Footwear Apparel
• Foul Weather Gear
• Mailport & PS Advisor
• Inside Practical Sailor Blog
• Activate My Web Access
• Reset Password
• Pay My Bill
• Customer Service

• Free Newsletter
• Give a Gift

How to Sell Your Boat

Cal 2-46: A Venerable Lapworth Design Brought Up to Date

Rhumb Lines: Show Highlights from Annapolis

Open Transom Pros and Cons

Leaping Into Lithium

The Importance of Sea State in Weather Planning

Do-it-yourself Electrical System Survey and Inspection

Install a Standalone Sounder Without Drilling

When Should We Retire Dyneema Stays and Running Rigging?

Rethinking MOB Prevention

Top-notch Wind Indicators

The Everlasting Multihull Trampoline

Check Your Shorepower System for Hidden Dangers

How Dangerous is Your Shore Power?

DIY survey of boat solar and wind turbine systems

What’s Involved in Setting Up a Lithium Battery System?

The Scraper-only Approach to Bottom Paint Removal

Can You Recoat Dyneema?

Gonytia Hot Knife Proves its Mettle

How to Handle the Head

The Day Sailor’s First-Aid Kit

Choosing and Securing Seat Cushions

Cockpit Drains on Race Boats

Re-sealing the Seams on Waterproof Fabrics

Safer Sailing: Add Leg Loops to Your Harness

Waxing and Polishing Your Boat

Reducing Engine Room Noise

Tricks and Tips to Forming Do-it-yourself Rigging Terminals

Marine Toilet Maintenance Tips

Learning to Live with Plastic Boat Bits

• Sails, Rigging & Deck Gear

Marine Wind Generator Test

Practical sailors search for the best marine wind generator for cruising sailors unearthed two new units that will give the old guard a run for their money. the german-made superwind 350 and a lightweight prototype of the air breeze from southwest windpower, churned out maximum amps during four days of micro-wind turbine test..

The micro-wind turbines assembled for this comparison include the KISS High Output Wind Generator, the Rutland 913, the Superwind 350, the Ampair 100, and a prototype of the Air Breeze. The four-day test period brought a good mix of light- and strong-wind days, so testers were able to review wind generator output in a variety of conditions. Wind speeds for the 4-day period averaged 12.6 knots, with two blustery days, so were not surprised the high-output, three-bladed wind generators topped the five-bladed ones overall.

                                                    ****

Last month, Part One of Practical Sailor s wind generator test “Choosing a Wind Generator,” examined the various types of marine wind generators on the market today, and discussed what to consider before buying one. That article also previewed some of the key differences between the five wind generators we tested in March on the shores of Chesapeake Bay. This article examines these generators in more detail and presents the results of our field test, which tracked wind speed and output of the five wind generators over the course of four consecutive 24-hour periods.

The turbines assembled for this comparison include the KISS High Output Wind Generator, the Rutland 913, the Superwind 350, the Ampair 100, and a prototype of the Air Breeze. (A sixth unit, the three-bladed Ampair 300, looked promising, but failed on the first day of testing. It has been repaired, and PS will be reviewing it in a future issue.)

The tested units fall into one of two distinct categories: three-bladed wind generators with large-diameter rotors and high maximum outputs (Superwind, KISS, and Air Breeze) and six-bladed wind generators with small-diameter rotors and lower maximum outputs (Ampair 100 and Rutland). As pointed out in last months article, there are key differences between these types of turbines. The six-bladed units generally begin generating power in less wind and run quieter. The three-bladed units deliver significantly more amps as wind speed increases.

Wind generator makers Hamilton Ferris and Four Winds Enterprises were asked to provide products for the comparison, but neither could meet the deadline for the test. We have looked at units from these manufacturers before. The Hamilton Ferris hybrid water/wind was reviewed in our Feb. 15, 2003 issue. The earlier version of the Four Winds II was among several units compared during long-term testing in 1994 and 1995 .

The long-term test (Nov. 15, 1995) evaluated several different wind generators, one at a time, over several weeks and monitored output. Ultimately, Practical Sailor concluded that although wind generators are effective at producing high output in ideal conditions, their output in the winds you can expect in a comfortable harbor is less than stellar when averaged over the long haul. Only one generator in that test, the Wind Baron Neo Plus (no longer available, as far as we know) delivered more than 100 amp hours over 24 hours, and none had an average daily output greater than 10 amp hours, which is less than can be expected from one 80-watt solar panel on a moderately sunny day. Until this year, one obvious question remained unanswered, however: How would various micro turbines fare if exposed to the same variable winds in the same location for a fixed period of time?

Air Breeze (prototype)

Southwest Windpower, makers of the popular AirX Marine line of wind generators, supplied us with a prototype of the Air Breeze, which will soon be sold through West Marine. The unit we tested was essentially the new Air Breeze software and blades housed in an AirX body. Note that

Practical Sailor is withholding any final judgment on the Air Breeze, until we are able to test the final product.

The specs for our tested model were not readily available, but testers were told that they closely mirror that of the production Air Breeze, described here. The Air Breeze will be available in 12-, 24-, or 48-volt DC models and has a rated power of 200 watts at 19 knots. It uses a three-phase, brushless permanent magnet alternator, which produces AC power that is internally rectified to DC.

Turbine control is via a microprocessor-based smart internal regulator utilizing peak power tracking. However, the Air Breeze also has an internal voltage regulator with a factory set point of 14.1 volts (12-volt turbine) or 28.2 volts (24-volt system). The set point is also field adjustable to suit different charging regimes (an AGM battery, for example). This setup allows the unit to self-regulate in high winds and to automatically stop when the batteries are charged. Normal charging resumes when the battery voltage drops slightly below the fully charged level.

The body of the prototype unit (as well as the Air Breeze) was powder-coated cast aluminum. Construction of the prototype unit was excellent. Like the AirX before it, the Air Breeze has a distinct, downward pointing tail fin with a small cutout. The manufacturer says this allows for better tracking of the wind and better stability in rough seas. Oddly, testers noted this unit had more of a tendency to rotate briefly away from the wind, even in a steady breeze, but this seeking didnt keep it from producing the second highest total output in our test.

The Air Breeze was by far the easiest unit to mount in our test. The base simply slides on and clamps to a 1-inch diameter schedule 40 pipe, providing 360 degrees of continuous operation. The blades were constructed of glass-filled polypropylene. The maker says an improved rotor and blades will be on the production model.

Start-up speed is reported as 6 knots, while maximum or “survival speed” is listed as 96 knots, with over-speed protection provided automatically by electronic torque control, and manually by an optional stop switch. The Air Breeze also uses stall control of the blades. According to the makers, this function is much quieter than it was in previous models (such as the AirX and 403), since the stall mode is activated by the controller before the flutter RPM is reached. The result is a dramatic reduction in RPM in wind speeds above 30 knots, reduced wear on blades and bearings in high winds, and&emdash;most importantly&emdash;protection of the turbine from damage due to high winds. Stall mode is activated at about 19 knots, and will stay in effect until wind speed drops below 19 knots. If the Air Breeze senses wind speeds above 43 knots, it will shut down completely for five minutes.

The Air Breeze finished less than 6 amp hours behind the best recorded output for each 24-hour period.

Bottom Line:

Pluses for the Air Breeze prototype include high output (second overall), light weight (lightest overall), quiet operation, easy installation, excellent construction, and a low price. The unit will soon be available at West Marine for $915, according to the manufacturer. Testers also liked the charge LED display on the bottom of the unit, which gives a visual indication of unit output and can be used as a troubleshooting aid.

The Air Breezes downside is its limited field repair options, unless there have been significant changes from the AirX unit it replaces.

One of two small-rotor units tested was the Ampair 100 manufactured by Boost Energy Systems of Berkshire, U.K. A six-bladed unit, the Ampair 100 has a maximum output of 100 watts and produces AC, which is then converted to 12- or 24-volt DC (selected at time of order) by two bridge rectifiers located in the units lower body. The DC output of the regulators is paralleled and passed to two carbon brushes (also mounted in the lower body) and then to two phosphor-bronze slip rings (mounted on the stationary pivot shaft) allowing the unit to follow the wind 360 degrees without the use of commutator brushes. According to the manual, maximum output current automatically remains at a safe level due to self-inductance of the heavy-duty windings&emdash;it goes on to say that similar sized machines (with low inductance and light-duty windings) have to be protected against burnout by the use of temperature-activated cut-out switches.

The Ampair 100 is built like a tank. The unit consists of a painted, two-part cast aluminum body with attached aluminum tail vane. Fit and finish were excellent, and all other inspected external components were either stainless steel or of composite construction. Internally, there are two six-pole permanent magnet rotors (with poles in line) mounted on a stainless-steel shaft, which runs in two sealed, grease-packed ball bearings. Two six-pole stators (one located in the main body casting, the other in the nose cone) are arranged with their poles staggered at 30 degrees to minimize “cogging,” which can prevent a rotor from starting in light winds.

Although the Ampair 100 produces AC, its bridge rectifiers are located within the unit base (eliminating the need for a separate box), so installation is essentially the same as a unit that produces direct DC. If a blade is damaged, it and its opposing mate will have to be replaced together. However, you can run the unit (at reduced performance) with two blades removed until you get your replacements.

Start-up speed for the Ampair 100 is approximately 7 knots, and while the maker designates no maximum wind speed (only that its designed to survive storms), its manual does state that its a good plan to secure the unit if a severe storm is expected. There is a stop switch option. Without this switch, securing the unit involves these steps: grab the tail fin, swing the unit out of the wind, wait for it to stall, then secure the blades with a rope or bungee cord. The Ampair has a hole in the tail fin so users can grab it with a boat hook or an attached line.

The Ampair 100 is designed so it can be stripped in the field to replace damaged or worn components. The supporting literature is the best of the group&emdash;a well-illustrated manual, exploded views with part numbers, a troubleshooting guide, as well as a suggested list of spare parts for cruising in remote locations.

The Amp Air finished last after each 24-hour test period.

Compared with the entire test group (large- and small-rotor units), the Ampair was very well-constructed and exceptionally quiet. Compared to its nearest competitor, the Rutland, the Ampairs heavier construction and the ability to repair problems in the field give it a slight edge for those cruising in more remote locations. Its downsides are its output (the lowest of all the units tested) and its weight (the heaviest of all units tested).

KISS High Output

Manufactured in Trinidad by KISS Energy Systems and distributed in the U.S. by Hotwire Enterprises, the KISS High Output wind generator is a large-rotor, three-blade unit designed with Caribbean cruisers in mind. The name being an acronym for keeping things simple, the KISS generator uses a low-key, yet effective design to produce a unit that is not only rugged, but also easily serviced “in the wild” with parts readily available throughout the world. Its three-year warranty allows for authorized repair by another facility while youre out cruising.

Available in 12-, 24-, and 32-volt models, the KISS generates AC that is converted to DC by a 30-amp automotive diode pack and then fed directly to the ships electrical system. It uses a brushless, three-phase alternator. As mentioned in our first wind generator article, one advantage to this approach is that theres less voltage drop in AC wiring than in DC, a plus for installations with longer wire runs (such as a mizzen mast installation).

The KISS can be shut down via the provided on-off switch and is also protected from overheating by two thermal-sensitive bimetallic circuit breakers connected to the coils of the stator.

While not as finely finished as the other units tested, the KISS is nonetheless well constructed and pretty much bulletproof. It uses a sealed fiberglass motor housing and weighs only 17 pounds (plus 13 feet of wire at about 6 pounds), making it the second lightest unit we tested. The motor fits directly into its two-piece fiberglass housing, which is bolted together (through the motor) with four stainless-steel bolts and sealed with silicone. (An oil seal on the motor shaft provides additional weatherproofing.)

Other features include an alternator designed specifically to match the low speed characteristics of the rotor blades, epoxy-coated neodymium iron-boron magnets and plastic sealed No. 6203 metric ball bearings (commonly available worldwide) which, as per the manual “ensures that maintenance will be infrequent, simple, and inexpensive.”

The KISS essentially comes in two parts: the generator body and rotor (which the blades are bolted to). The blades are highly cambered with twist, taper, and elliptical tips for maximum torque at relatively low RPMs and reduced blade noise. Each blade is made of five layers of bi-axial glass roving, pressure molded in polyester for strength with minimal flex and very light weight. All three blades are bolted to the rotor, which screws onto the threaded motor shaft.

The three blades are selected at the factory to have similar dynamic weights, however final balancing by the customer is required once installed on the rotor. This is a straightforward process accomplished by trimming a strip of lead tape attached to each blade. The reason given for having the customer balance the blades was so they would be better balanced upon assembly (after shipping). If you don’t want the hassle, Hotwire Enterprises will pre-balance the blades for an additional $25.

As the blades are sold as sets (based on similar weights), the company recommends replacement of all three ($210) should a single blade be damaged. However, you can keep undamaged blades as emergency spares, balancing them with the spare lead tape provided.

The KISS is the only unit tested that did not use some form of rotary contact (a feature that allows multiple, 360-degree rotations). Instead, the unit comes with a tether connecting the tailfin to the mounting post, allowing the unit to turn no more than three revolutions in either direction. The manufacturer states that its rare that the unit will turn 360 degrees. A light spring installed in the mount tends to turn the unit back to the forward position when the wind stops. Optional mercury-contact slip-rings providing infinite 360-degree operation are available from Hotwire for an additional $200.

Start-up speed for the unit we tested was advertised at 7 to 8 knots, and while the KISS is guaranteed to hurricane winds, thermostats in the motor will begin cutting output at around 20 to 25 knots to prevent overheating. The KISS produced noticeably less power than the other three-blade units on the windy Days 2 and 4. The manual states that youll probably want to shut the unit down above 25 knots. This can be accomplished by utilizing the electric stop switch mounted in the control box.

The stop switch will slow the blades to a near stop in winds up to 42 knots (allowing you to secure the blades with a line). You can also manually shut down the unit using the line from its the tail to swing the tail into the wind. The KISS does not use set screws to attach the hub to the shaft, so its very easy to remove the blade assembly and stow below for hurricane preparation. The housing itself presents little windage. The KISS banked the most amp hours on Day 1, and was the only generator that did not record its highest output on Day 4.

The strong points of the KISS include simple, robust construction, excellent output for the tradewind cruising for which it was designed, and last&emdash;but certainly not least&emdash;the ability for the owner to repair virtually all aspects of the unit in the field. Downsides include slightly higher noise levels, the requirement for the customer to balance the blades (not due to difficulty, but as an additional step and potential problem if done incorrectly), and lower overall output than the other large diameter units tested.

Rutland 913

The Rutland 913 is the second six-bladed, small-rotor, wind generator featured in our test. Output of the Rutland 913 is 12 volts DC, and it is manufacturer-rated to deliver up to 250 watts. It is designed to provide power (via a battery or bank of batteries) to 12-volt or 24-volt systems. At $995, it is the least expensive production model we tested.

The Rutland 913 features all marine-grade materials and stainless-steel fittings. Highlights include a high-inertia generator, stator windings developed without an iron core (for low friction and low start-up speed), fiberglass encapsulated stator coils for reduced stator failures, and dual-encapsulated single magnets (eliminating the need for multiple, glued into place magnets).

The Rutland also features automatic thermostat protection (for use during prolonged high winds) and a start-up speed of 5 knots&emdash;the lowest of all the units tested. A shut-off switch is available with the optional HRDX charge controller ($295). The standard HRS charge controller is $149.

The Rutland 913 was not as heavily built as the Ampair, but construction was of a high quality. The Rutland comes pre-assembled with the exception of the blades and nose cone, both of which were very easy to install. The six turbine blades are a glass-reinforced nylon composite.

If a blade is broken, it should be replaced along with the opposing blade to maintain balance. However, until replacements are installed, the 913 can still be operated by removing every other blade, so that it is still in balance.

The Rutland manual doesn’t list a maximum operating wind speed. It does mention that higher winds may trigger the units built-in thermostat to prevent the generator from overheating. If it does, output stops, and the turbine will temporarily speed up until the units internal temperature drops back down to normal, after which it starts charging again. The manual indicates you may see this cycling in prolonged winds (particularly in higher ambient temperatures), and that if storm winds are forecast, you may want to secure the unit to minimize wear and tear.

The 913 “is designed for continuous running to achieve maximum resistance to water ingress,” and if restrained for any extended length of time, it should be covered.

The Rutland 913 does not have a stop-switch option. Stopping is essentially the same procedure as with any wind generator without a braking option: Grab the tail, swing the unit out of the wind (180 degrees), and once the unit stalls, throw a rope around a blade or two and tie to the mounting pole.

Theres a small hole in the lower lobe of the Rutlands tail assembly to make this operation a bit safer by allowing you to grab the tail with a boat hook. You can also install a small tagline through the same hole to make it safer to grab whenever you need to secure the unit&emdash;just be sure it wont tangle in the blades.

The Rutland 913 was the quietest unit in our test group, having a slight edge over the Ampair 100, its closest competitor noise-wise. (Not surprisingly, the two small-rotor units were the quietest of the group). The Rutland was well-constructed, had the lowest start-up speed and the quietest operation. Compared to the other small-rotor unit, the Ampair 100, it produced more and was quieter (although only slightly so). The decision between these two boils down to the Ampairs rugged construction and repairability versus the Rutlands slightly better performance.

The Rutland 913 finished next to last on every day except when the wind was light on Day 3, when it was 0.5 amp hours behind the Superwind.

Superwind 350

The Superwind 350 is a three-bladed, large-rotor unit manufactured by Superwind GmbH located in Bruhl, Germany, who recently signed on U.S. distributor Starboard Sun Corp. of Amherst, N.Y. ( www.starboardsun.com ).

The Superwind is a 350-watt unit that produces DC current and is available in 12- or 24-volt output. Similar to what youd see in larger wind turbines, the Superwinds rotor control system adjusts the pitch angle of the blades for power and for limiting rotor speed, even during extreme wind velocities. In winds over 24 knots, the rotor control system adjusts blade pitch to keep power output constant.

The Superwinds fit and finish were excellent. The generator body, rotor, and tail assembly are powder-coated “sea water-proof aluminum.” Total weight for the assembled unit is approximately 25 pounds. Features include a no-maintenance, permanent magnet design incorporating neodymium magnets in a three-phase generator with an internal rectifier. The Superwind comes with a three-year warranty on parts and workmanship, however, it does have some basic exclusions, such as floods, lightning strikes, fire, etc.

The Superwind is delivered in three easily assembled parts: the generator body, rotor (which the blades are attached to), and the tail, or wind vane. Each carbon fiber-reinforced blade is mounted to the rotor using two flush-mounted, stainless-steel Allen head screws. The blades come balanced from the factory, meaning if one blade is damaged, youll have to replace all three at a cost of about $250, plus shipping. It was the most difficult to install, requiring that you measure, drill, and tap two metric holes in the schedule 40, 1 1/2-inch tube to accept the mounting bolts. An optional adaptor for mounting on 2-inch diameter steel or aluminum pipe is also available.

The Superwind produces DC, so the electrical installation is pretty straightforward and well-documented in the manual. Due to high power output, installation of a battery charge controller and a stop switch is highly recommended. Superwind sells its own controller for $480 and a stop switch for $89.

The Superwind manual has a basic troubleshooting flow chart, but if its anything more complicated than replacing damaged blades, swapping out the carbon brushes or checking for blown fuses, youll likely have to send the unit for repair.

The Superwind edged out the Air Breeze with overall output, and was the top performer in every period, except the first, when it recorded the second lowest output total.

The Superwind was the overall winner with regards to putting amp hours in the proverbial battery bank. It was very well constructed, relatively quiet for a large-rotor unit, and performed well, even on the lowest wind day (relative to the other models). Its downsides include limited field repair options, a hefty price tag, and the fact that it is a newcomer to the U.S. market.

Clearly, we are looking at two different animals here: quiet, lower-output, five-bladed units that deliver power on most days when theres a breeze; and three-bladed units that can bank some serious amp hours when the wind is up. Although the test period was relatively short, it brought a good mix of light- and strong-wind days, so testers were able to monitor output in a variety of conditions. Although isolating each period is instructive, the final average for the four days is, in our view, the most useful number.

Wind speed for the 4-day period averaged 12.6 knots, with two blustery days, so were not surprised the high-output, three-bladed wind generators topped the five-bladed ones overall.

The Superwind did the best on every day, except Day 1, when winds mostly hovered around 10-12 knots. Most striking was the Superwinds superior performance on the mostly light-wind Day 3. More importantly, Superwind was a robustly built unit that ran quietly while it went to work. It is also the second heaviest unit and the most expensive by far.

If there is any concern we about the Superwind (besides the price), its that its new to the U.S. and only recently signed on with a distributor here. Wind generator makers have come and gone over the years, and we hope this one&emdash;started in 2004&emdash;sticks around.

The Air Breeze prototype looks very promising and might even have been the Best Choice, except that we have not tested the actual unit that will be for sale. If youre not in a hurry to buy, you should wait for our update on that model. The KISS, which climbed to the top on Day 1 and placed third in output overall, is our Budget Buy for high-output models, and would be well-suited for tradewind cruising. It suffered in winds less than 10 knots and was slightly noisier, but it is well built, and for DIY types, it is eminently serviceable.

Of the silent running, six-bladed wind generators, the Ampair gets a recommendation for serious cruisers who want “built-like-a-tank” construction, and repairability in the field. The Rutland 913 is our Budget Buy in the five-bladed category. Based on our testing, it is the most affordable route to quiet windpower and superior output in light wind conditions.

RELATED ARTICLES MORE FROM AUTHOR

Leave a reply cancel reply.

Log in to leave a comment

Latest Videos

40-Footer Boat Tours – With Some Big Surprises! | Boat Tour

Electrical Do’s and Don’ts

Bahamas Travel Advisory: Cause for Concern?

Island Packet 370: What You Should Know | Boat Review

• Privacy Policy
• Do Not Sell My Personal Information
• Online Account Activation
• Privacy Manager