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

Wednesday, October 7, 2009

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

Fair points...wet batteries could probably ruin your day.

AGM's can supposedly run submerged...On the Rawson, I believe the owner wisely left room under the batteries - occupying all the bilge capacity would definitely be an issue. To me, one of the reason LiPO4's are attractive is that the "flatpack" form factor would allow placing the batteries right up against the hull - lower and out of otherwise useful storage area - but still dry.

-Keith

--- In electricboats@yahoogroups.com, Jason Taylor <jt.yahoo@...> wrote:
>
> In my uneducated opinion, placing lots of batteries in the lowest part
> of the boat is a bad move. I can see running hard aground being made
> much worse with a bilge full of batteries. In my production boat at
> least (a 1978 Beneteau First 30) the original head sink configuration
> did not include a seacock and when heeled over on a port tack in some
> conditions, the sink could siphon seawater into the cabin. The thought
> of all that water going straight down to the bilge on top of my
> batteries scares the heck out of me. Absolutely everything I have ever
> read about where to locate batteries has listed keeping the connections
> dry as a fairly important factor. In my mind, keeping the batteries out
> of the bilge is more important than getting the weight down that low.
> Under the settee berths, in the space of the old engine, under the vee
> berth are fine. Of course, my boat has 4" deep bilges so the point if
> moot in my case. I would store bottles of rum in a deep bilge, but not
> batteries.
>
> /Jason
>
> aweekdaysailor wrote:
> >
> >
> > 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
> > <mailto:electricboats%40yahoogroups.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.
> >
> > >
> >
> >
>