Elco Motor Yachts, the Athens, N.Y., electric motor manufacturer, showcased its EP4000 AC on the Hunter e36 Hybrid sailboat. “There’s no smoke, no noise, no vibration,” Elco senior vice president Kevin Kearns says. The AC motor is 93 percent efficient, compared with 45 percent for most diesel engines and 25 percent for 2-stroke gasoline engines, he says. Kearns says that at $8,500, the cost is comparable to a diesel system. The lithium batteries last six to eight years, and the motor, which is sealed and has just one moving part, requires servicing once every 50,000 hours to repack the thrust bearing, he says. “Range is 46nm at 5 knots on batteriesonly” and “A range of 812nm at 5 knots using batteries and generator as a hybrid with 50 gal of fuel. Operating cost is about 8 cents a nautical mile. The 12-volt batteries are rechargeable from shore power, solar panels, a wind turbine or a 14-kW generator. “You can get to hull speed instantly with a generator running and dead batteries,” he says.