We all know that electric-powered boats are cheaper to operate than gas- or diesel-powered models, right? But exactly how much cheaper are they? Now the creative people at Stephens Waring Yacht Design up in Belfast, Maine, have come up with some numbers to answer that question.
Oddly enough, hard figures are hard to come by. So, Stephens Waring started their research at the Alternative Fuels Data Center at the Department of Energy, which has a lot of drop-down menus with information about cars, comparing the costs of an all-electric Chevy Volt, for example, to the costs of a combustion-engine-driven Volkswagen Golf.
This leads to the idea that the basic efficiency of an internal combustion engine is only 21 percent; about 80 percent of the energy it produces is heat and is blown out in smoke. An electric motor, on the other hand, is about 95 percent efficient, meaning that 95 percent of the energy in the battery is turned into usable motion energy. Then there’s the problem that an internal combustion engine and transmission have about 2,000 moving parts.
To compare boat costs, Stephens Waring looked at the all-electric Hinckley Dasher (pictured above), with a 28-foot waterline length and a weight of 6,500 pounds. They worked out speed-to-length and weight-to-power ratios and determined that the boat needs 39 hp to go 10 mph. They then determined that it would cost $657 in diesel fuel to drive Dasher 1,000 miles. The all-electric version, based on the cost of Kilowatt hours, would be only $360.
Take a look at all their assumptions and reasoning here: