Wind Generator Placement

[JamuJoe]

Most wind generator installations that I see are at the stern on a pole or arch, where the wind flow is often blanketed and the noise source is close to the cockpit. I am planning my installation of an Air X on my Leopard 42, and am inclined to place it on a bracket near the top of the mast, just above the forestay/jib furler. This will better ensure unobstructed wind and maximize distance to the noise source. It will still be well clear of the wind instruments at the top of the mast. Are there any concerns regarding length of wire run, maintenance, or anything else that I am not thinking of? Has anyone a better suggestion?

[Hud3]

I've seen that sort of arrangement, but usually as mizzen-mounted wind gens on ketches. Don't see why it wouldn't work well as long as you properly size the wiring, and don't mind the climb.

[GordMay]

Originally Posted by Hud3

I've seen that sort of arrangement, but usually as mizzen-mounted wind gens on ketches. Don't see why it wouldn't work well as long as you properly size the wiring, and don't mind the climb.

What Hud says.

[SailFastTri]

If all you ever want to do is sit at anchor and you're sure you'll never sail in a severe squall, it's a good idea.

Is sailing performance important? You will create turbulance ahead of the main and effectively eliminate any benefit from your mainsail in that area. Other disadvantages include adding a major weight and windage aloft -- at the end of a large leverage arm (your mast) -- this will greatly increase your chances of capsize in a storm. Do the math on that -- it's scary.

Safety and performance should be a higher priority than your other concerns. Why waste a good sailboat?

The amount of wind interferance from mast and rigging on a stern pole-mounted wind gen is negligable. Any vibration from aloft will be trannsmitted yo yhr cabin by the mast. Noise? Live with it or get more solar panels. (JMHO)

[Zanshin]

In addition to what was said above, I would worry about the weight and the very long arm up high. My D400 weighs 15Kg and I wouldn't want that weight and inertia at the end of an arm 40 or more feet long.
(A nice long paragraph with a sample calculation deleted once I realized that a "Leopard" is either a tank or a catamaran and tanks rarely have wind generators)
I think about the forces acting on a windgen at the top of a mast on a cat would result in more stress on the standing rigging than the designers planned for. Again, it is a matter of weight x arm.

[craig boorman]

With most newer cats, permenent sun roofs are common which make great platforms for solar and wind devices. Have you folks looked into the vertical axis wind gens? Thinking they will do well on boats Vertical-Axis Wind Turbines: The Future of Micro Wind? [w/video] : CleanTechnica

[JamuJoe]

Thanks for the comments. Safety is always my primary concern, and maintaining anything high up the mast is an issue for me. Actually, the weight of this wind generator is approx 17 lbs and the placement on a bracket 6 ft below the masthead should not significantly affect either the airflow on the mainsail or the masthead instruments. My comments pertain only to large cruising catamarans - which of course are much different in design characteristics from monohulls. The moment arm would be well within the design loading of the mast on this particular 42' catamaran. Heeling and wind-driven capsize is not an issue - the rigging should fail prior to forces that could result in capsize, which is why prudent early reefing is particularly important on a catamaran. My observations on noise and blanketed airflow of stern pole-mounted wind gens come from conversations with owners of similar catamarans (large mains and long booms extending past the arch) with whom we have been out there cruising in the Western Caribbean.

[Scott730]

Craig
Do they make one for the marine industry?

[senormechanico]

Having had both a wind generator and later a decent solar array, I think the best place for the installation of a wind generator is on ANOTHER boat at least 500 feet away from where I'm anchored. I'll stick with solar panels as they're a lot quieter and not as dangerous.

Steve B.

[Sailabel]

We were also concerned about noise from our Air-X when we installed the unit, and have heard horror stories from other cruisers about the noise that these units emit. Our initial approach was to sand and varnish the blades, which reduced the noise considerably... to a point where it didn't bother us aboard our boat, and when we asked neighbors in anchorages... they stated that our unit was not objectionable. Our Air-X is mounted on pole that is integral to our radar arch http://www.sailvictoriarose.com/images/arch%203.JPG

The aftermarket blades at www.silentwindgenerator.com have been getting quite a bit of favorable comments on other cruising bulletin boards. We'll be purchasing a set of these as we head out again.

Steve

[SailFastTri]

Originally Posted by senormechanico

Having had both a wind generator and later a decent solar array, I think the best place for the installation of a wind generator is on ANOTHER boat at least 500 feet away from where I'm anchored. I'll stick with solar panels as they're a lot quieter and not as dangerous.

Steve B.

Hi Steve. I'm with you on that -- but I'd rather have a neighbor with a wind gen than one with engine-powered gen.

Best Regards,
Larry

[fastcat435]

We have installed 3 wind generators ( air Breeze on top of the mats and the arrangement gives nothing but pleasure , the picture above is of the first FastCat with this installation an the owner is very happy with it.
The power output is at least double of what one would get from a stern mounted unit , even going downwind she still generates some energey.
A owner of a Leopard 46 ( tulliano) is also please with this installation.
I have got drawings on how to install ( safe )

Gideon

[Bash]

(and I've never yet met someone with a masthead-mounted wind generator who wasn't pleased with the installation.)

thanks,

John.

[SailFastTri]

Originally Posted by Bash

(and I've never yet met someone with a masthead-mounted wind generator who wasn't pleased with the installation.)

thanks,

John.

They probably stay in the harbor and never go sailing. It's not safe to put an extra 25-35 pounds of high-windage stuff at the top of your mast. You should ask any reputable boat designer what they think of the safety implications as it relates to capsize, righting moment, and stresses on rigging.

[Bash]

Originally Posted by SailFastTri

They probably stay in the harbor and never go sailing.

Indeed, the person I most recently spoke with about this rig sailed from Tahiti to San Francisco last summer. And the first time I saw a similar rig was in an anchorage in St. Lucia, used by a couple who claim not to have spent a night in a marina in three years.

Might I suggest that you're oft-repeated concerns about capsize might only be applicable to small boats that most of us would not consider appropriate to cruising? Once you carry more than five tons of ballast, ten kilos atop the stick isn't going be all that scary.

Were a "boat designer" to tell me that a wind generator atop the mast would capsize his/her design, I'd be looking for a better designer, perhaps even one who has studied marine architecture.