Windgenerators - the differences

[Orchidius]

Hi there,

As some of you might have followed in my previous threads, I'm currently building an arch on the back of the boat to support solar/wind. Now I'm looking into what gear to get to mount on the arch, and since every company claims their product is the absolute best and has graphs to support that, it's becoming quite the challenge...

I've had some great input from you guys concerning the solar panels, and I think I have that part figured out now. Now I have the same question about the windgenerators: how is their efficiency measured?

They come in multiple Wattages, so that's easy enough to spot. The rest of it is a bit less clear. I assume the amount of wind it needs to start producing is crucial as well, but that's not always noted as clearly.

Any input on this? I'm looking at the following for example:

Apollo 550 w Watt 12 V AC 3BLADES Wind Turbine Generator Land Marine Use | eBay

[barnakiel]

Looks another incarnation of AirX. Not?

Bad karma. Neighbours will hate.

Install, switch everything off and measure with your monitor instrument.

b.

b.

[donradcliffe]

Swept area (blade diameter) is THE most important factor--the rest is all marketing BS.

[Orchidius]

How come the fancy new ones all have those narrow blades then? Good for noise reduction I guess, but horrible for performance?

[Ocean Diamond 2]

Hi All,
I just installed a silentwind on a arch bar on the stern and Im really happy with the quietness and output.
I went for the new model that can also take 600 watts of solar.
Derek

[Hannah on 'Rita T']

No wind generator is quieter than the D400, do your neighbors a favor.

[Jim Cate]

Originally Posted by Orchidius

How come the fancy new ones all have those narrow blades then? Good for noise reduction I guess, but horrible for performance?

No, this has nothing to do with what Don said. Swept area is the area swept by the blades as they rotate, not the actual area of the blades themselves. Swept area is directly related to the amount of energy available to the turbine at any given wind velocity. Differences in blade design affect the efficiency with which the turbine extracts that energy. Alternator design then affects the efficiency with which that energy is transformed into electrical energy for your boat.

We have been fairly happy with our old Air-X for a decade or so. If I was to need another set of blades I'd go with the Silent Wind replacements, but we don't find the originals all that annoying. Others disagree with this, some with considerable angst, but if one looks around any cruising anchorage, Air-X and its derivatives are the most common units in use. Gotta be a reason!

Cheers,

Jim

[MTang]

How are the newly redesigned KISS?

[model 10]

We switched from a Air X to a Sunforce 600w. It makes way more power and is very quiet but, it's huge, it puts a noise in the VHF in high wind and it stops charging to soon. They have the controller set to stop charging in about 30+ knots even if your batteries are low. So the wind is blowing like crazy but you have low batteries! The radio noise is something you would be stuck with because it is 3 phase AC and hard to filter out, or maybe it would not affect your boat..

[Aslan]

I personally enjoy the sound of wind generators. If you have a noisy wind generator I'll probably raft up to you.

[natew]

I've had one for two years. Works great, is way, way quieter than the old model air-x that it replaced and it starts up in way lower wind speeds. The manual explaining the wiring was a little incomplete so it took some thinking to get it all wired in correctly but other than that i'm happy with it.

It shutsdown at 30knotts because that is where the self protect mechanism is set (which I think is standard). My old air-x actually flew off it's mounting pole because the self protect mechanism in it burnt out in a 45 knott wind it now sits somewhere at the bottom of the pacific, I was sad but incredibly happy that it departed off the stern of the boat and did not take any solar panels, sails, or other equipment with it.

[robert sailor]

Why do so many cruisers mount these above the solar panels shading the panels under many conditions??

[cwyckham]

Originally Posted by robert sailor

Why do so many cruisers mount these above the solar panels shading the panels under many conditions??

Because there are precious few places to put one on a monohull

[model 10]

Originally Posted by robert sailor

Why do so many cruisers mount these above the solar panels shading the panels under many conditions??

There are not that many choices. With just one mast you don't have much choice. Maybe moving the solar panels but again where? We also have a radar scanner, several antennas etc. providing shade for our solar panels.
I notice that now you can buy single solar cells and perhaps make your own panels. This might change things as you could make custom solar panels to fit in some other places. At a recent boat show there were several displays of solar cells put into a lay-up of a thin fiberglass sheet. They were a bit flexible...