Low Power Wind Turbine

[britinusa]

At a rough count, we are pulling about 8 amps max when sailing using the Auto Pilot (GPS, AIS, VHF, AutoPilot, Refrigerator), but let's say it's 10 amps.

10Amps at 12Volts is 120Watts.

We have 350 Watts Solar (but we all know it's never going to produce that even though we are in South Florida)

So, I've been considering a Low Power Wind Turbine (btw, Pet Peeve is when folks call them Wind Generators! - They don't generate Wind!!)

Most all of the smaller wind turbines on line are 400W and have a Blade diameter of about 3' or more.

I'm thinking that a small low power wind generator would be a power benefit while sailing (no need for it when motoring)

The really small (40W to 80W) turbines I've seen online get mostly POS reviews

Any one have any experience of a low power wind turbine, or ideas on the subject.

Yes! I have read pages of reviews here and on cruising forums.

Oh! Happy New Year everyone!

Paul

[Noah]

My neighbor has the Air-Silent-X. It is very good. Works well in light air and is very quiet. Dont ever hear it from the dock. Considering one myself. I do not have solar, as I don't have a bimini . I have a cockpit tent connected to the dodger that I errect for shade if needed when not sailing.  So far in So. Cal haven't needed a real bimini. Nor do I want to spend for/make an "ugly" arch structure to ruin my boat's lines/chi.  I may cave and reconsider that and solar, too.  Note to consider when thinking about wind power, it is not too effective when going down wind, as your apparent wind is reduced and thus the turbine's efficiency.

https://www.downwindmarine.com/Air-Silent-X-Marine-Wind-Generator-p-91003629.html

[Jon W]

How many amps do you average per day from your 350 watt solar system?

I believe it's called a wind generator because it generates electricity using wind as the mode of force. Most are brushless alternators (would have to check if also PMG), not generators.

[britinusa]

How many amps do you average per day from your 350 watt solar system?

Not to sound critical, but it really depends on the Day! On cloudy days it can be zero, in Summertime we have seen as high as 10amps, but average, I just don't know.

If we're at anchor overnight! Then it's zero 

Just toying around with an idea for a 40W turbine which would just about power the fridge which is on 24hpd when we're onboard.

[Alex W]

Keep in mind that wind power is a cubic function (KE=mv^2).  The 400 Watt rating is probably calculated at around 30 knots of wind.  When sailing at 15 knots apparent you won't get 200 watts... you'll probably get 40-50 watts.  The reputable manufacturers should provide a test curve that takes into account the efficiencies of the blades, magnetics, etc.  I would think that if you want 50 watts in average sailing conditions a 400 watt turbine is about right.

[Noah]

According to specs claimed by below manufacturer;  90 amp hours per day at 12kts. average apparent wind.
https://www.downwindmarine.com/staticPages/Primus_AIR%20Breeze_AIR%20Silent%20X_Specs.pdf

[britinusa]

Yes, it seems that most turbines start to output around 7mph which would produce nothing in still air at cruishing speed or below, eg. at Anchor.

My thought is a lower power turbine that does generate 'some' usable power at those lower air speeds.

If it produced 4amps (48watts) that would run the fridge, which would be a big part of the load.

[Noah]

Paul- "Cruising speed in still air"? Wouldn't be an issue as you would be motoring with your alternator out-putting. At anchor, if totally calm, ok, no output. As an addition to solar and/or to keep or top off batteries from fridge and house loads, might consider wind.

[britinusa]

Paul- "Cruising speed in still air"? Wouldn't be an issue as you would be motoring with your alternator out-putting. At anchor, if totally calm, ok, no output. As an addition to solar and/or to keep or top off batteries from fridge and house loads, might consider wind.

Ha! Yup, got me there! :)

How about Sailing in 7kts of True Wind.

[Noah]

Upwind you would be generating fine. Downwind nope.