The Offshore Voyaging Reference Site

Wind Generators

In recent years, with more people going ‘off-grid’ in yachts, RV’s and remote cabins, micro wind generation has come a long way, largely through the adoption of new materials and technologies such as neodymium permanent magnets. Some of the latest generation of wind turbines can produce really acceptable amounts of output around the clock in the right circumstances. But there are still limitations:

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Paul Mills

Hi Colin,

We have a D400 on Sakari and are very pleased with it, finding it starts producing some power at rather low speeds – when many other boast wind generaters are stationary, and then performing strongly after 10 knots. Compared to many it is very quiet, particularly when running at a constant dpeed with wind below 20 knots. I would echo the weight issue, lifting it up onto its pole above our arch was just doable without a ‘sky hook’. It can vibrate a little and I have traced this to a slightly worn mounting bush at the top of the pole, and the screw that holds it down onto the same.

We do not have an off switch and so have a piece of cord to grab to feather the blades and then loop around to stop it restarting….. I call this process ‘taming the beast’ and when it is turning at full chat I dread to think what it would do to my arm if I lost focus at the crucial moment.

My favourite thing about a generater this size is that when we are sailing anything but downwind it makes enogh electrickery to run all the instruments and the autopilot – perfect.

Best wishes


Colin Speedie

Hi Paul

Sounds like a good report for the D400,

But I’d really want to fit a stop switch. Having to clamber up to grab the tail or cord isn’t easy when conditions demand it. And as I’ve got a scar on my shoulder from the consequences of contact with the blades from doing just that, I should know!

Best wishes


paul mills

indeed it can be a bit edgey, I have a line from the fin that makes a loop round the bottom of the post – much easier to grab….

you can get a stop switch and the manufactures warn that it should only be used to then tie up as in strong winds the blades can still turn and create damaging charge within the generater itself.

Overall the d400 is definitely something I would buy again



Hi Paul
When I tie off my Aerogen I grab the tail & turn it at least 90 degrees; can do 180 degrees. This uses the wind to stop the spinning. Easy.

Geir Ove

There is Silentwind.

Colin Speedie

Hi Geir

This is a new unit to me, but the output (400W) and the weight (6.8kg) look attractive.

Have you, or anyone else out there got one, to let us know what your opinion is?

Best wishes


Matt Boney

We have the DuoGen which has the same regulator and output but of course also folds down into the water as a towing generator. Because the shaft can be dropped down to change the blades it is easy and safe to tie off. It needs a bit of wind to get it going but twice we have had 40 amps output and blown the 35 amp fuse. The manufacturers say put in a 40 amp one. They also say DON’T use a regulator if you are living aboard, just tie it off when you leave the boat. Solar and Wind regulators can and do interfere with each other because the wind genny output is not constant so can turn its own regulator on and off when it is not running fast because it “sees” the battery voltage as being high from the solar regulator. Two of my colleagues have had this problem and disconnected their wind genny regulator. Most of the time you batteries need all the help they can get to reach 100%, so don’t disconnect your potentially best source of charging.

John Harries

Hi Matt,

Sorry, I missed your comments in all the anchoring ones. Interesting and useful first hand experience. Thanks very much.

Ismo Falck

I have tested a Silentwind wind generator. I have used it about a year now. I am very pleased to it. It generates electricity well. Last summer I sailed about 5 weeks without any other source of electricity except motoring in and out from harvour. Blades are amazingly thin and sharp. Work quality is excellent. This unit wont disturb anybody near my boat. In higher winds there is some resonance inside the back cabin. I have to look the vibration dampening more closely. It is nice that in the same regulator I can put solar panels too (when I buy those). In regulator there is wery informative display, where I can read how much unit creates power or has created during longer period. It slows down when batteries are full or if it starts generate too much electricity to batteries. There is also stop button.
So far it looks very promising to me.

John Harries

Hi Ismo,

Thanks for the useful real world experience based review.

Randall Wallace

I know this is an old thread, but it’s like old magazines. Store them out of sight for a few months and they’re new again!? I’ve had a Silentwind for 5 years now and it’s a good unit. Sound is minimal and differs from the D400 in that with the Silentwind you don’t hear the blades at all – only the hum of the rotor. Just the opposite for the D400. But again, both are comparatively quiet, just a bit different. The D400 seems to start with wind just a few knots lower than the Silentwind. But they’re both running at 8 knots. I did have a front bearing go bad, but it was easily replaced in St. Martin with an off the shelf $10 bearing by a technician. He showed me how to fix it myself and provided an extra bearing. Haven’t needed it. The Silentwind comes with an external charger that has a cut off switch and cumulative monitor of output.

Simon Fraser

Hi Colin,
We have a three bladed earlier version of the Air turbine on China Moon, and it certainly can shriek when the wind gets up! I believe that while the peak power output of some generators may be high, that if they don’t start until the wind gets to say 10 knots they are unlikely to produce as much power over the months as a nominally less powerful generator which spends more time generating, at lower wind speeds.
One of the theoretical and practical points about three bladed turbines is that they require all three blades to be present for balance and therefore for rotation, so if one blade fails (or disintegrates at great speed) you have nothing.
The six bladed turbines can be balanced with 6, 4, 3 or maybe even 2 blades, so you have a few opportunities to salvage something by repositioning the remaining blades, which seems like a very robust situation for the Adventure Cruiser.

Colin Speedie

Hi Simon

Those Air X units are so noisy – we have had one near us (100m) at times this year, and when it blows the racket it makes is appalling.

I take your point about some of the lower powered units that start to deliver power at low wind speeds. But I think that in practice the fact that they still don’t deliver appreciable amounts of power once the wind speed climbs means that they still underperform against one of the high output units. The Practical Sailor trial demonstrated this well, I thought.

I do like the look of the new Rutland 914i, though.

Good point re the blades – I hadn’t thought of the useful ability to continue without a damaged blade. We carry our old, original, set as spares, though, which explain that.

Best wishes


C. Dan

This is great – keep it coming!

One thing that would be helpful is to put each part of the system in context of the energy budget – please don’t assume that we already know this.

Maybe a separate post with a couple energy budget scenarios would help?

Colin Speedie

Hi C. Dan

There are so many variables, that it’s not easy – but I’ll do my best as I sum up at the end.

Glad you like the posts so far – thanks for the kind words.

Best wishes


Svein Lamark

I have an Air x 400. I t was very noisy and gave little power at light winds. I have this summer changed the blades to the blue carbon type from Spreco. I got the blades directly on the factory in Portugal to a low price. The result is great, little or no sound from the mill and much more power at weak winds. After the installation of new blades I put the generator on with no shore power and left the sailboat for 5 weeks sailing another boat. When I came back the battery showed 14,2 volts. Almost too good.

Colin Speedie

Hi Svein

Sounds like a good deal – I’m intrigued by the power increase in light winds, though – I wonder how they have managed that?

But anything that makes an Air X quieter is worth having, even if it were to do nothing else!

Best wishes


Matt Marsh

Nice summary Colin, I think you hit all the main points well.

While I’m impressed by the CFD work that has gone into the new near-silent blades, I must admit to being sorely disappointed by the engineering in some modern wind turbines. This is not new or complicated technology; there are plenty of mid-1920s Jacobs units still in use. Yet we still see some flaws in modern units that were solved 90 years ago- runaway speed in a storm, for example, used to be prevented by self-feathering blades on a centrifugal governor. The Superwind still does this, but some others rely purely on the electronics – and, eventually, on the owner wrapping a lasso around the thing.

Regarding vibration: A stiffer mounting structure will often go a long way towards preventing vibration problems, or at least making them mild enough that rubber bushings can take care of the rest. An unsupported 2″ pole is an open invitation to nasty resonances.

Colin Speedie

Hi Matt

It is indeed remarkable that at this stage we’re still the same old faults. Electric switches can fail, and its a lot to ask of them to stall a generator spinning at max revs in a storm. And stopping them manually and lashing them off can be plain dangerous in bad weather.

In my experience poles can work OK if they are kept short and solidly based – but long poles where there is scope for the pole to move and create wear are a recipe for vibration – and you’ll be switching the unit off……
Best wishes


Paddy Delaney

all are good units , I got so frustrated several ago because most genny’s were not set up for marine enviroments , I went and redesigned my own unit , if you or anyone has any questions regarding wind generators or desalinators please contact me

the main problem with most generators is the bearing they used , they are not radial lip sealed type for high speeds , the next is the motors cant produce constant power as the windings have a lower copper content because they are machine wound , next is the internal lube used in most units have a low melting point so they produce more sound , next is most are not totally sealed units , then there is the blades , they must flex and even carbon composite blades need to be painted to cut down on resistence , and off course the ever present balance , the unit must be completely balance to have all weight centered dead center on top of the mounting bracket which should be powder coated , never look at a unit that doesnt include a controller …….open the controller and make sure it is 100% coated and sealed in at least 1/4 inch to 1/2 inch of resin , braking and supplied on/off switches are a given
as a result and this is straight engineering most are not set up for the harsh marine enviroments …….again if anyone has any question about thier current unit [stopping vibration or reducing operating noise or just making it work more effectively ] just contact me

tks Paddy

Giles Oakley

Dear Colin,

Apologies for resurrecting this thread.

I have just bought a 435 & want to mount a Rutland on the transom arch. Can you buy a bracket or did you have yours made?



Colin Speedie

Hi Giles

Ours is custom made. The top section consists of a base turret with a floor that is the same radius as the arch. The upper part of the turret is a 6″ section of tube with reinforcing webs to stabilise it, which are also welded to the floor which is c. 3 x the diameter of the tube. A tube of suitable length with the same OD as the ID of the turret is then cut to fit the wind generator base fitting.

The turret is through bolted through the upper and lower surfaces of the arch, and a similarly sized and radiused base plate to the turret underneath the arch. All parts (except for the bolts) as in matching 5086 alulimium.

It’s a stiff and detachable set-up, that you should be able to adopt/adapt to the Rutland.

Best wishes



Thanks Colin – very helpful. I will set about finding a metal worker in Bristol.

Denis Moonan

Just a plug for the KISS. Installed in 2006 (mounted on a 8′ ss post) and along with 2 x 130 watt fixed solar panels. Result? I have cruised mostly in the Bahamas and the SW Caribbean since and often go for a week at a time w/o resorting to the portable Honda or the Yanmar auxiliary for meeting our 100 -110 amp hr/ day requirements (mostly refrigeration). I do have a big house bank (860 amp hr deep cycle wet cells which went 7 years before replacement). It is not the quietest, but very reliable and maintenance free. I wonder if the new US built units are improved at all as the old blades on mine are pretty crudely made. We don’t live in a cave but we do not have a TV. Life is good!



Matt McGahran

I’d like to be added to the list

Michael Kornfeld

Would love to hear any more recent experience comparing the D400 with Superwind 350 (with the quitter blades) wind generators. The Practiical Sailor comparison sadly omitted the test on a D400, even though they are widely used.


I just installed a 400 watts permanent magnet triphased wind generator from Newmeil ( The hardest part was to install the tube because of the mechanical requirement of such an installation. Having a metal boat, it was a welding project. The wind generator is now solidly held 10 feet above the deck. Its about noiseless until the wind get to 20 knots. It is at this speed also that is really start generating. Having 800 Amp of battery, anything below 10 A is just tickling the batteries. But at 20-25 knots of wind, the noise outside of the wind through the mast, sail, bimini made the wind generator disapear in the background noise.

Triphased alternators need higher speed than traditionnal brush generator to produce but they are mostly maintenance and worry free. There is only a coil, some magnets and 2 bearings in the housing. All the rectifiers and current management are on the remote box which is installed inside. A benefit is the cable can be gauge 14.

Very satisfied.

John Harries

Hi Andre,

Thanks for the real world information, always the best kind.

Hague Showell

Hi Andre,
I have recently bought and installed a Newmeil X400 turbine to replace my old AirX400 (which I am about to pull apart and restore). The Newmeil runs beautifully quiet and low start up speed and looks/feels well engineered, but so far I have not been able to get it to produce satisfactorily. The voltages produced at the controller seem to cycle up and down from 2 or 3 volts to 13 or 14v even in steady winds of 20 knots and output through my shunt is 0 amps.
It came bundled/packaged with a Hybrid solar / wind controller suited to street lighting and I believe this is the root of the problem.
The nature of the Newmeil is that it produces wild a.c. current which the controller rectifies and regulates and the output is only as good as the controller (unlike the AirX which internally regulates and produces d.c. output direct to battery). I believe the problem is that the controller sees the battery voltage as high and whilst for example one might have taken 50AH from the 480AH house bank of AGM batteries, the turbine output is not being sent from the controller because it is still seeing a high 13v or more on the house battery bank. Unfortunately the hybrid controller that came with the turbine does not have a means to adjust the preset charge off setting.
I think I may buy another dedicated wind controller that has adjustable settings. The provided controller does properly regulate my solar panels so I will keep it for that.
Has anyone else seen this problem or have experience with tri phase turbines that could help?
Port Adelaide

John Harries

Hi Hague,

Sounds to me like you are right about having a poorly programmed regulator and that you need a regulator that you can reprogram, I can’t help further with this specific case, since I have no experience with the Newmeil, but I do have several chapters in our online book on batteries that explain the theory behind charging and regulator programming that may help:

Hague Showell

Hi John & Andre,
Thanks for the feedback both.
I am reading your chapters on battery management, John… most helpful thanks.
I’ll post again on the Newmeil turbine when I have a programmable dedicated wind turbine controller installed and tested (to replace the bundled hybrid controller) and look forward to hearing how you go with your new controller Andre.
BTW Whitworth Marine in Australia were the supplier of the Newmeil and let me report that they were most unhelpful in trying to source another controller or even to contact Newmeil for their advice on the problem. Newmeil also I have not yet been able to contact through their website – all bulk chinese orders i guess being supplied to the likes of Whitworth Marine.


Hi Hague
I am aware of the variance in output, i also asked my reseller to provide me with a programmable controler – and still waiting for it. The boat has a 800 Ah battery bank (lead acid golf cart type) which are not easily impressed by a small charge like 10 or 20 and i also have a MPPT charger from solar panels (550 Watts total). I have noticed that when the battery bank is at 90-95 % capacity, the wind turbine is unable to kick in if the solar panel is producing – whatever the production. But i have deliberatly let the battery bank go at 70 % just to see and then i saw the wind vane kicks in whatever the production of the solar panels. So i agree with you that being able to adapt the threshold charge parameters of the Newmeil turbine would help greatly !

I’ll be doing tests with an MPPT wind controller later this winter and come back reporting here.

Hague Showell

Thanks for your reply & info Andre and look forward to your test results.
See also my reply to John above.

Richard Waite

Thanks for the useful info Colin – and others. I’ve just replaced an old AirX. With re-trimmed blades and dodgy bearings it was telling me something – loudly. After looking at the options and budget we decided on a Rutland 1200 (3 blade, AC, supposedly 40w at 10knots maxing at 480w at 27 knots). This comes with an external MPPT controller / limiter that also accepts up to 20 amps of solar (which is more than we will have space for but may not be enough for some). I’ve fitted two small solar panels on deck (total 110w) and will supplement this with mobile panels (two 55w panels in a fold-up plywood ‘briefcase’).
Tahira (Tayana 42) is on shore here in the UK over the winter … but I will report back on this combo once we’ve been on board a few months.

Rudy Heller

Great info. I have a nice two panel solar set up on my Kato Arch and they produce well. When having the arch built, I included a extra riser in the middle for a future wind generator to be installed later. We will cruise in about 10 months, and I am debating on whether to add the wind gen due to shadowing of the solar panels, or wait and determine the average panel output. Anyone have any experience or comments on what impact the wind gen shadow has on your average solar output? Clearly, any shadow will have an effect, I am just not sure whether it is significant enough to worry about in the big picture Thank you.

Marc Dacey

I don’t have a comparison and I suspect the variables of time of day, azimuth of the sun versus the direction of the wind, and whether one is on the hook or on passage (and where) would create a lot of different results. I can predict, however, that in breezy conditions, the panels will have significant output for five to six hours a day, shadow or not, whereas the wind generator can be going 24 hours a day. If the wind generator is producing four times as often (potentially) when the panels cannot (and we aren’t even counting cloudy days at noon), then the question seems of only passing interest. If you are in an area of very steady winds and a constant boat orientation that does not favour your panels, that’s a different story.

Eric Klem

Hi Rudy,

We had a wind gen on our last boat and solar on this boat. As a general comment, wind generators can work great in places that are consistently windy like the trades but actually don’t put out that much in many other areas. You can look at the rated output versus windspeed for the units and calculate how many hours at what windspeed will be equivalent to the output of one of your panels and you will find that it needs to be reasonably windy for a good portion of the day. I originally selected a wind generator on the theory that if it wasn’t windy, we would be motoring and charging that way but with our home base in New England (solar panels were also much more expensive at the time so I was trying to avoid that), that proved to be a mistake, we mainly sail but the winds were rarely enough to produce significant power. Our solar has a much higher output and has been easier to deal with all around.

The harder subject is when you have the opportunity to add both. The output of your panels will be greatly affected by any shading so limiting it is crucial. With most arches that have both solar and wind, at least one solar panel has greatly compromised output most of the time. I would suggest making a cardboard profile of a wind generator and monitoring current (batteries need to be low enough to be in bulk charge) while you hold the profile over the panel to simulate shading. If your results are anything like what I have experienced with shading, you will likely be better off without the wind generator unless you are in an area with constant strong winds including overnight. A friend thought that they would increase production by adding a wind generator in a setup similar to yours and found that net power production was lower actually due to how much less the panels output.

Whatever you do, if you get a wind generator, make sure you get a quiet one. I have been on a number of boats with somewhat audible ones and it is amazing how much it changes the experience.


John Harries

Hi Eric,

Thanks for fielding that with real world experience.

Rudy Heller

Thanks all for your feedback. As we are planning to cruise in a variety of areas and conditions, I think I will just “piggy bank” the money for the wind generator and see how things go. Assuming I can access one, it will be relatively easy to install one once the need has been confirmed. In the mean time I will enjoy the solar output. Rudy

Carl Johanson

Great input from all of you more experienced than me. My way of sailing in the Scandinavian archipelagos may be very different from most of yours.
I am very happy with my Aquair 100 in wind mode. I often do not really need charging during the day when sailing so then I stow the wind generator below deck. When moored for the night I will hoist the Aquair with a head sail halyard as high as possible between the mast and the forestay. There, 10 m above deck, the wind is better and I do not hear it at all. It takes a few minutes to rig it with halyard and three downwards lines to bow and starbord and port chainplates respectively but it is a part of the mooring routine. I hope to use the Aquair in water mode for long passages but I have note yet tested that mode.

John Harries

Hi Carl,

Sounds like a good way to go, and certainly fits in with my fixation on clear decks!

Philip Waterman

I have just completed a year living with with a SilientWind 400+.

The unit is extemely quiet once up and running although some low frequency noise finds its way in to the aft cabin when running slowly. This is probably due to the rather tall pole in my installation to get the blades well above stretched-out arm height. (I have no gantry/arch)

A few of important discoveries :

1) Spend time on the installation getting the blade tips perfectly equidistanced. Only a couple of mm difference will lead to resonances at certain speeds.
2) Using the manufacturers recommended cable cross-section (or one higher) is critical for the multi-phase ac to controller connections. This was a significant investment in my installation.
3) To get anywhere near the quoted 400W into moderatly discharged batteries requires a lot of wind >30kn!!

My only negative experience is related to my last point. When there is sufficient wind to generate significant power the conditions are often gusty and the unit will go into over-rotate shutdown. In the case of my model this is an electronic (ie magnetic) brake which shuts the unit down for a period. It then spins up, generates good power for a bit and then a gust shuts it down again. This is less of a problem on a passage away from land, however at anchor a common occurrance.

I don’t really see why the “intelligent” controller can not use a PWM scheme to feather the braking effect at excessive speeds, at least until a potentially blade damaging over-rotate condition has existed for a period. It is possible that the brake is simply shorting out the ac connections with a relay in the control box so perhaps there is a cost issue in getting intelligent control of the braking effect.

All in all a good bit of kit though.

John Harries

Hi Philip,

Thanks for a great report that will help others.

Devon Rutz-Coveney

Nice report Philip,
I too am using a Silent Wind 400+… for about 2 months now…. after almost 30 years of using different brands of wind generators, this is the best so far… It is really amazing how quiet the blades are, especially when they are balanced equidistant from each other as you mention and the manufacturer recommends.
It is very powerful BUT like you have pointed out, it takes a lot of wind.
I have stuck to the wire size recommendations exactly.
The biggest problem so far: the unit shuts itself down in sustained 25-30knot winds, well before the battery set point voltage is met.
So sure, it may be rated to 420watts, but for how long?
The big issue for us, after the shutdowns, it does not start again without doing a ‘Total Reset’ (as described in their manual April 2019 ver April 2019, pg 27). This involves more work than what I envision it should… especially if it going to be a continuing issue…
In previous turbines we have used, mostly the SouthWestWindpower/Primus units, the rectifiers/controllers located within the turbine itself would overheat and fail…..
During the mid 90’s in Tonga, with their 303 version of the turbine, we went through 4 of these controllers in a season!
In later versions (after SWW recognised the heat issue), they shut themselves off and one doesn’t get the benefit of what the machine is purposed for: making amps!
I am hopeful that the people at Silent wind will be able to fix the issues… I think it is a software issue in the controller…. waiting for the manufacturer to respond.. With the controller located remotely I’m not sure that heat is the issue…
If so, a computer fan wired to the DC output on the controller will be my hack/workaround.
Hope this is helpful to people interested in the technology.

John Harries

Hi Devon,

Great report, thanks. The number of charging devices shipped with poorly programmed regulators never ceases to amaze me.

Ee Kiat Goh

Hi, Does anyone have experience with Sunforce 400 wind generator? Yes, I am shopping for a wind generator and at the moment the Air Breeze is a good contender. The Sunforce 400 is half the price and twice the output sold in Defender. Another question I have on charge regulation is that most wind generator require you to connect direct to the battery where it can sense the battery voltage. But what if the battery voltage is the voltage of the solar panel/alternator that is charging it. What happens? Is there anyway to have both solar and wind working together at their max capacity with prevailing wind/sun conditions? Bearing in mind that it is almost impossible to overcharge our batteries on these generators..

John Harries

Hi Ee Kiat,

I don’t have any experience with the Sunforce 400. However I can answer your second question: For a full understanding how regulators and charging sources interact you need to read our Cruising Boat Electrical Systems online book. Start at chapter one and put particular attention into understanding the first two chapters.

Ee Kiat Goh

Ok, thank you John.

Timothy P Lamarre

Ok, I was hell bent on the D400–until I started to try to figure out how I would mount it on my 37′ yawl. Hmm…a 12′ pole rising between mizzen stays? Ugly and windage. The mizzen is there–it would be most logical to use that. Well, on the top? Too much leverage and not accessible enough. A bracket on the mizzen? There goes the mizzen stays’l, my favorite sail. I am just guessing that a D400 mounted on the front of the Mizzen would interfere with stays’l. Would I even be using the D400 when the wind is off the aft quarter? Could I just tie it off and fly the stays’l. Initially gun, I am now leaning towards scrapping the idea of a wind generator. Any input?

John Harries

Hi Timothy,

I think you are making a smart call. Compromising your boat’s sailing capability for a wind generator is, at least to me, a poor trade off. I looked at wind-generators a few years ago and came to the same conclusion: too much drag and clutter. And then there is the noise issue too. More here:

Ee Kiat Goh

I have just purchased the Air Breeze generator based on the recommendations on this post. Thank you. I am now planning to install it on a 2 inch diameter pole at the stern. Does anyone have any experience with this unit with regards to vibration damping? Is the vibration bad? what can one do that is tried and tested.

Matt Emerick

Are the ‘charge resistor and dump resistor’ you mention the same as the ‘voltage regulator’ you mentioned previously? I just want confirm any potentially bad assumptions. Thanks!,

John Harries

Hi Matt,

It’s unlikely that colin will reply, see #3

That said, I think that the dump resister Colin is referring to is part of the regulator. The point being that the current that would normally go to the batteries and loads needs to go somewhere when the former are satisfied.


I’d like to hear if anyone has field experience with the Eclectic Energy D400 wind generator.


Arne Mogstad

Old thread, but just thought I could add my thoughts after a year with a wind turbine in case it would be of anyones interest.

I have an AirBreeze mounted on the stern arch on my OVNI pretty identical to Colin’s setup. My boat is almost never in a harbour, it lives on anchor more than 95 % of the time, and almost totally rely on renewables for charging, plus occasionally the engine alternator when necessary. I live in Northern Norway, so solar panels have virtually no benefit for several months of the year.

The wind generator works okay, it makes noise, but very manageable. The problem is mainly in low wind, as it makes noise but doesn’t generate any appreciable amount of power (think less than 25 watts). In higher winds, it seems to make less noise(?) and the rigging makes much more noise then anyway. I generally turn it off under 8-10 knots of wind, because I find that the yield is not worth the noise.

Being this far north, through the winter it would be impossible to rely on solar. The wind turbine alone is even able to increase the charge in my batteries on windy days with the Eberspächer heater on and using lights and electronics. I have been living comfortably onboard for a week on anchor in -10 degrees, only powered by the wind generator, staying over 70% charge the entire time. When the boat is left on its own for some days (no heater on etc), it will keep my batteries topped up.

Keep in mind that the winds here during winter are often strong, so I am more often losing output because the generator shuts down due to overspeed protection, rather than too little wind.

That being said, I don’t think a wind generator is a very good solo-source of electricity. The regulator does not have a stable enough energy source (fluctuating winds) nor a good enough regulation to charge lead acid batteries all the way to 100% (caveat: I have only used the AirBreeze, other regulators may work better). The solar MPPT’s does a much better job there in my experience. And hence I tend to top the batteries off while motoring or with the occasional harbour visit during the dark months.

With my usage-profile, I would not be without the wind generator. However, if living in an area where sun is more stable and prominent, and winds not being “guaranteed”, I am not sure I would have wanted a wind generator, due to cost, annoyance, the hazard, etc. Solar doesn’t annoy your neighbor, it won’t chop off a hand, and installed correctly, you don’t have to worry about it in bad weather.


John Harries

Hi Arne,

Great balanced analysis of the plusses and minuses of wind turbines, thanks.

I have never had one, primary because of the noise and windage but can certainly see the utility during the dark time in Norway.

Ee Kiat Goh

Thank you Arne for your post. I have the same wind gen as yours and solar panels with a MPPT controller. I am however in Sunny tropics with no winter. i installed the wind gen just before the covid outbreak in 2019 in Thailand. Due to the lockdown, i could not get to her from Singapore. The blades are now 3 years old with little usage and due for a preventive maintenance change in case they break with serious outcomes. I agree with you that the wind gen needs more than 15 knots to get maybe 4 to 5 amps. At speeds lower, they make a lot of noise and appears to be working hard but general little amps. I think it needs wind speed between 25 to 30 knots to make it worth its while. Then again, a sailing friend of mine swears by them and they have 2 Airbreezes !

John Harries

Hi Ee Kiat,

Yikes, two wind generators, the thought of all that drag when sailing the boat with the wind forward of the beam gives me the horrors. Might easily make the difference between clawing of a lee shore, and not.

Andre Langevin

I have a Silentwind. After 6 months in the Lesser Antilles, altough the trades were blowing 25 knots for days… the 1 kw of solar panel has always succeded to refill the batteries at 10 am. I consider having installed a windvane an error, i will remove it because i don’t see its value and its a dangerous apparatus to maintain in top condition. I’ll rather install a hydrogenerator for long passages.

John Harries

Hi Andre,

If it isn’t working for you in the Eastern Caribbean with all the good wind that’s common there, then that’s conclusive for me. Except in special use cases like Arne in the dark time, solar just makes way more sense. Thanks for the report. I also agree on hydro for long passages, just makes way more sense.