Regen Electric Drive is Perfect for Sailboats.
The people bitching about how it won't work are looking at the wrong side of the coin.
Sure, how long you can run an electric motor (without a generator) depends on the size of your battery. And how long you can run a diesel depends on the size of your fuel tank. It's only an issue because diesel stores energy more compactly then batteries.
I look at a sailboat as being propelled primarily by wind. Yes, it's nice to have backup propulsion to get off the dock, or out of a tight spot. Now if you want to motor for days without wind (or too much wind) then you don't want a *sail*boat!
I would look at electric drive as backup propulsion. The beauty of it is that it *never* needs fuel. The same machinery can recharge the battery bank while you're sailing for free. If you're already going at hull speed any extra speed/energy is wasted anyway. It can even recharge (slowly) at anchor from currents or tidal flow. Your house power for stoves, computers, heaters and air conditioning is also free!
In best case, you don't need *any* diesel generator; the system charges itself. In worst case, in a calm, you are stuck; when you have wind you can sail; motor when you have power; sail if you run out of power and recharge; and motor some more; all with no fuel! In heavy weather, you can do the same, or anchor, or use a sea-anchor, charging all the while. On long trips it might prove superior to a diesel because you would never run out of fuel!
Now, I might like to have a small generator as a backup - backup. But probably nothing like the size of a propulsion diesel. It would charge the batteries slowly, or propel the boat slowly if need be.
Aside from the genset, the system can be much simpler, much hardier and much more versatile then a diesel engine. If the batteries end up stored in the keel and used for ballast, that would make it even greater.
I guess this is what separates the motorsailors from the rest of us; the ones who want that genie in the bottle always on call below decks instead of keeping a weathereye out, and your wits about you, and prepared to do a bit
of heavy sailing in a pinch, or relax and wait out a calm. Isn't that what sailing is about?
Jim Baranski, Franklin ME
17' Siren; looking for a bigger old boat!