T-Pain Is On A Boat: [Electric Boats] Re: Boats over 30'

Tuesday, June 2, 2009

[Electric Boats] Re: Boats over 30'

SailingPM (other names?... I care!),

Mark Stafford here echoing Keith (aweekadaysailor). He has lot's of water credit. Sure start small, get some performance numbers, but plan to at least add another motor (dual motors driving your one prop shaft). Two 19 peak hp motors will give you adequate thrust (90% - 99% hull speed) for short term "situations". 48volts of 8 Trojan T105 should give you a safe 10 minutes of high dual motor thrust, provided you auxiliary cool the motors. Hardly enough to battle adverse wind and current for transport, but plenty for short safety maneuvers.

The HondaEU2000i is great, but inadequate since it can only slow charge one battery at a time. 8 Honda 2000's would be cumbersome, but make you a happy motor/sailor. Alternatively, a more expensive DC genset would make you an ecstatic motor/sailor. I am still looking into those for myself (55' x 10' Herreshoff in Berkeley).

Mark Stafford

--- In electricboats@yahoogroups.com, "sailingpm" <sailingpm@...> wrote:
>
> I've been reading this board for a few years now and have since gotten my own boat over 30' and have been waiting for the right time to jump in. I know nothing of the technical electrical stuff but from what I've read here and see what's available for sale. I am mechanically able to create my own set up, but I guess the question always comes back to power, and juice, which for me is still hard to determine will be enough. Below is my info, but I still need confirmation that this is suitable and/or reasonable. Thanks for the great posts. I'm still learning much.
>
> Union Polaris sailboat
> displacement type hull
> 36' on deck
> 32' waterline
> 22,000 lbs
> perkins 4-108 (taken out)
> 100 gal diesel tank (taken out)
>
> The challenge for me is to be able to mosey motor (3 knots?) out of the Alameda Estuary to the Gate and back on battery power in mild wind and at slack water. By then the batteries should be down to 80 - 70%? I will have a honda 2000 generator for anything further and to stop depleting the batteries. Speed is not so important. But I figure this is the range I'd like to make me feel comfortable on batteries only at a reasonable pace.
>
> I'm looking at one 48 volt Etek-RT
> 8 - 6 volt trojans for 48 volts
> mounted a la thoosa style with the pulleys and such at 2.3:1.
> My prop is 15", but I don't know pitch. It is in an aperture behind the rudder.
>
> Is this a reasonable starting point for a setup? I've seen a similar setup in the photos section in Vallejo.
>
> Thanks for sharing.
>