Scaled Down Cruise Ship

Yes, your idea is feasible. A 65’ displacement hull moving at 10 knots can realistically run on under 50 hp if the hull is designed efficiently. Low speed and careful hull design make solar-electric propulsion practical.

 

The whole SOR is full of contradictions. For example, crossing oceans at 10 knots with a beamy boat that has lavish accomodations and supplies for several persons. However, assuming 50HP at 3 gal/hr to cross New York to Lisbon is approximately 3400 miles. That would use 1020 gallons or 7242 lbs with no reserve. It also assumes that there is a dead calm all the way. It is not realistic.