'Motor yacht is a whie fiberglass box designed to carry furniture on the hump of resistance
The key for being 'Green' is to chose the right boat for the task. Most of motoryachts today are designed to run not over 200 hours per year, for them performance and fuel efficiency are not important, but marina fees is the major expense. It means that the designers are trying to fit maximum of luxury accommodations into the platform of 'niche size'. These boats do their job, but when it comes to real cruising, charter or other commercial use, such 'white boxes' should be avoided and special designs should be commissioned.