While researching sailboats with the latest diesel-hybrid technology, I noticed an interesting question on a Magnet DC manufacturer’s message board:

Do you produce motors, and systems large enough to provide power for a catamaran boat of 40 X 28 foot, and what speed could this achieve.

Looking for a Diesel electric propulsion system to achive +- 12 knots to sruise the Indonesian Islands

The answer was not only yes, but they gave a suggestion to check out the current MW Line boats, which are solar-electric:

The running costs are 20 to 45 times less important than for the equivalent powered motor boat.

Add a sail and you have some incredible speed/comfort/sustainability. I suspect that these advances also make a navy nervous, given the applicability of the technology (silent, odorless, less supply required) to everything from submarines to zodiacs.