It's pretty crazy that the article does not state how many theoretical watts the yacht has. It looks like maybe 4,000 watts from the photo of the panels.
From memory its a 5.4kw array with 8kw motor. At 400w it can (on a calm inland sea) cruise at around 3 knots. Top speed of ~9 knots.
Its made from plywood so its super light. he wants to take it across the atlantic, which I think is brave given that its not got any compartments(that I could see in the video), so any breech means it'll sink in minutes.
I mean an outboard would do, but then you are limited by range, also its noisy as hell. Sure you _could_ install an inboard second hand cummings with 10k hours. but thats not cheap or easy.
So you're left with outboard motors. They are cheap and don't vibrate the entire boat, but they are still noisy. Plus they aren't actually that much cheaper to buy than electric.
but then there is the running cost, it'll be (at uk prices) about £3.50 an hour to run on diesel, vs £0 on solar.
Plus all the extra space for not having to install fuel tanks.
my issue is more that the hull is untested and doesn't look all that strong.
But yes the bigger problem is the hull, that clearly isn't ready for difficult situations and this is why I said that. If you just want to have fun it's not really worth it to spend all that money for mediocre capacity when you could have gotten a decent experience for much less.
I really don't get it, a sail boat makes much more sense if you just want to have fun without relying too much on a noisy motor.
It may even require ballast, which the batteries can pull double-duty for.