Finally! This is long over due. About five years ago, I had the opportunity at the helm of a solar only powered passenger ferry on a channel here in Germany. The vessel was similarily laid out, maybe a tad smaller than this ship, and of course not as black, though already pretty cool. Unfortunately, it never went into regular service due to stupid public water transport laws that could not be easily adapted to this kind of power train. What a pity, they had to scrap it. Good luck with this one!

This is still a ways off from a solar powered cruise ship, but given the option, I’d cruise solar 100% of the time over diesel, gas, or natural gas power.

5 knots isn't much slower than the average speed of a sailing vessel. Throw a sail kite on to give a boost when it would be reasonable to do so and you'd be golden.

Dj_dunrider, you are correct. 5 nts is a good speed. If you were to do a round the world cruise it would be enough and sailors do use some diesel is most cases. Also you often stop for a week here and there as you go because you are not out to really sail around the world nonstop but to have fun. During these stops the battery would top off. I wonder how fast you could go with full batteries and solar for one day?

There are better ways to go For instance a kite sail can not only move the yacht but generate power through the prop sand can be automatically deployed. There are few boats that 1 person doesn't control everything. And you generally island, post hop with only a few long ocean sails.

I am not a yacht aficionado but this solar powered craft could have added a pair of concealed masts to compensate the shortfall of 800Kh batteries, sail while the batteries are being charged also, for a good measure a pair of stabilizers with additional solar cells would add capacity and sail around the globe non stop.

I admit to not knowing much about boats, (I'm more an airplane kind of guy) but isn't 78ft rather small for an ocean voyage? Seems like you'd get tossed around, a lot, in heavy seas.

What the hell do I do if there a prolong thunder storm and cloudy days at sea?

What would this solar yacht cost? Any idea?

Neat concept. I am curious as to who would be the customers though. The people that can afford one can also afford fuel...and usually do not like to waste time in transit. There are many large boat owners that don't even ride their boats in transit because they don't want to spend the time...so maybe slow is not bad. I would love one...but I could never afford one so it is a pipe dream. The idea of being largely independent is huge for me as well as sailing cruisers. Hope it works.