Toured the boat, saw it hauled out in Honokohau for a quick bottom paint job. The boat is indeed well equipped... and that electric engine is sealed into a watertight space under a dogged hatch. It looked like the heart of a Swiss watch. The boat is ready to go and the couple had it all loaded and was on their way out when they discovered that there were no good reliable trades to give them the "push" to the Marquesas. So they came back.
The solar panels provide enough "juice" to power the engine for 4 or so hours of motoring, then you have to wait for the system to recharge... They had 4 batteries devoted to the engine alone, and I believe he said it was a 48V set up. They had one battery devoted to "house." And of course they had a wind generator.
The boat is an Aries 32. It is really fully rigged for long offshore trips, with everything from the solar panels to a nice Monitor wind vane steering set up. The cockpit was very tight and cozy. They had a great instrument package on board too.
With the solar setup, if you did get into the doldrums, you'd have to wait, charge and then motor, but you can keep doing that as long as there was good sun. With a diesel, once you have exhausted your fuel, there isn't much more you can do. In some respects, the solar makes more sense as you truly are self sufficient.