If this was on a lake and you only had to deal with the occasional headwind I'd say that 10Kw (13HP) was enough, but not in a 4 mph river current. I use my Torqeedo on a 12' john boat on the Wabash and its typical 2-3 mph current is formidable.
Concerning the hull form, I'd take out the severe rocker. Putting in a flat bottom admidships will give you greater pitch stability, reduce draft and power requirements, too.
--- In electricboats@yahoogroups.com, Keith Jacko <nrixez@...> wrote:
>
> I'm interested in building an electric house boat. The basic concept is an easily driven houseboat, strictly displacement speeds (6 - 7 mph), powered by an electric outboard. I'm thinking about a 10kw outboard. The boat as sketched would displace just a little under 6 tons to sit on her lines. Here are a few pictures of the boat sketch (and a .skp file if anyone wants to play around):
>
> http://www.dwdogs.com/Fusion/
>
> I'd love to go with a ~40 kwh LFP pack, but reality probably has me sticking to around 20 kwh. There is enough space on the roof of the boat to fit 2 kw of solar panels. More if I really stretch it, but I'm thinking 2 kw should be enough.
>
> Basic boat dimensions: 32' x 8' with a 16" draft. At 12,000 lbs with the proper center of gravity, the bottom of the transom would just be touching the surface of the water.
>
> I live in Minneapolis, and this boat would be for cruising on the upper Mississippi and St. Croix rivers. Fairly sheltered, and no currents greater than 4 mph (hopefully less most of the time).
>
> The boat will be built with plywood covered in glass / epoxy. I do plan on having fairly thick cabin walls for a boat... 2x4 construction, with closed cell foam insulation / floatation in the walls, hull, and cabin roof.
>
> Any feedback about the sketches or general idea? I'm designing this as a liveaboard, and I plan on living on the hook as much as possible.
>
> About the outboard, I'm not really sure how to figure the proper prop size, pitch, and rpm to shoot for. I understand the general rule of thumb "bigger prop, slower rpm, better"... but I don't know much past that. Could an electric outboard like say the up and coming Parsun 10 kw efficiently drive a heavy displacement boat like this? Or would it be better to think about using an inboard instead, so I would have the flexibility to tailor the rpm to my liking? I really do like the overall project simplicity of an outboard, but if it's really less than ideal I could consider alternatives.
>
> Thanks for your thoughts and feedback. Cheers!
> -keith
>
