T-Pain Is On A Boat: Re: [Electric Boats] Repowering 40' 1975 20,000 lb sailboat

Tuesday, October 6, 2009

Re: [Electric Boats] Repowering 40' 1975 20,000 lb sailboat

Gday all
Replacing keel mass ( in a sailing vessel) with batteries is going to affect your boats stability curve, and quite possibly then any insurance cover you may have, as you are altering an original design parameter pertaining to safety.
rgds
Alan

----- Original Message -----
From: aweekdaysailor
To: electricboats@yahoogroups.com
Sent: Tuesday, October 06, 2009 6:17 PM
Subject: Re: [Electric Boats] Repowering 40' 1975 20,000 lb sailboat

Futher confirmation that the "sweet spot" - sailboats < ~30' holds.

The combination of cheap mass-produced components (golf carts...) in the appropriate power range (6HP) and the ICE weight-credit to energy-capacity/range curve make this a very viable target. Much over that, and the power requirements start to overwhelm the load-bearing capacity of the vessel using lead-acid and the budget of the owner if using LiPO4.

AC Motor with AC generators maybe? It's just a series-hybrid at that point but could still be supplemented with a big inverter/charger and a moderate battery-bank for harbor maneuvers.

Denny has suggested taking some weight off the keel to compensate - that would help push the envelope to larger boats. In fact the first time I read about an electric conversion it was a concrete-keel Rawson 30 where the owner had chisled out the concrete to make room/capacity for the batteries. Not too many of those available unfortunately, so we're left with chopping lead (or iron...)

Hollow (filled fiberglass) keels on some boats?...hmmm...

Any marine architects on the list?

-Keith

--- In electricboats@yahoogroups.com, <joec_43@...> wrote:

> I received two prices for converting, and without batteries, is getting close to $12,000 US. Out of my ballpark, and no savings in the long run at all.

>

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