Interesting there aren’t any solar panels. I guess the weight would undo the charging benefit for most customers? I wonder if folks will add them after market or if it’s just not useful for a watercraft like this.
I figure that's especially true for boats, which aren't usually daily drivers. If you use your boat, say, twice a month, it could be a nice feature to have the battery partially or completely refilled when you want to use it without having to bother to plug it in.
Rule of thumb for a boat motor is 1hp for each 40-50lbs of weight. Say conservatively that you're 160-200lbs like myself, that's 4hp minimum.
Solar panels are ~15w/ft^2.
4hp = 2983w, which is ~200ft^2, or approximately a 14'x14' panel.
There's some fudging around that can be done around letting it charge for part of the day, but even with those extremely generous numbers you end up with an enormous "sail" of solar cells.
For a planing hull, maybe?
Displacement hulls (sailboats, trawlers, etc) don't need (and can't make use of) much hp. It doesn't take much to get to hull speed, and basically no amount of power will make it go significantly faster.
For example my 8000lb sailboat has an 18hp engine (~440lb/hp) and it could easily reach hull speed with a smaller engine in most conditions.
Let's say the boat can easily add solar panels to collect an average of 200 watts for 10 hours a day. That's 2kwh per day, or enough to fully recharge the boat in 40 days. If you go boating once every two weeks, then that's a third of a full charge for free.
Is that worth it? It depends. It seems like a nice feature to have, and it adds some additional weight and complexity to the boat, and increases the manufacturing cost somewhat. The hardest part might be explaining to customers that solar panels don't increase the range and they'll have to plug in to charge if they want to use the boat every day.
It might make sense if you incorporate solar panels into large sails, but the engineering required to make it work (main problem: too much weight; not enough elasticity) is essentially unsolved for now.
Some people might want to use a boat infrequently, and not near charging stations. But perhaps a speed boat isn't the type of boat someone would choose for this due to lack of sleeping quarters, fridge, etc.?
For speed boats? Probably not. Those things are small and incredibly power hungry - going fast on the water is expensive in terms of power used.
10kW of panels, 2x30kW motors (or 2x150kw for more $), 75kWh battery (150kWh for more $).
I forget where I saw it but iirc cruising at 5kts was less than 10kW out the screws. Meaning you can do 5kts for as long as the sun is up, and then for 7.5 hours more off the battery. If you want to do 9kts (on that short a hull) you're looking at like 50kW and therefore it would drain the bigger battery in 3 hours.
A rough rule of thumb for solar panels is they're worth four hours of full output a day, so that panel setup is good for about 40kWh/day. You can either use that to travel 200 miles, or use it to charge up the battery. It very neatly fits the 100 mile/day + 2 - 5 days at anchor travel lifestyle of most "cruising" catamarans (sailboats).
This guys youtube channel is cataloguing all the electric and solar boats he can find: https://www.youtube.com/c/JimWaltz/videos
Whats most interesting to me is all the indian/thai/phillipine solar ferry's that are getting built. Those are not eco projects, those are people finding niches where this really is the more economical choice.