They are starting to exist, this is one thats already been produced and sold so has some real-world numbers: https://www.silent-yachts.com/silent55/ https://www

They are starting to exist, this is one thats already been produced and sold so has some real-world numbers: https://www.silent-yachts.com/silent55/ https://www.silent-yachts.com/silent55/ 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 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.