PLUGGED IN

Back in 2015, I'd mused on these pages that my son, Evan, then in kindergarten, would likely own an electric-propelled boat. Now he's in middle school and can operate a boat on his own. Has electric propulsion matured to where my light-hearted prediction might actually come true?

To find out, we repowered an iconic teenager's first boat, a 1970 13-foot Boston Whaler Super Sport, to see how Elco's EP-50 electric outboard and lithium batteries stack up against the boat's 40 hp Johnson gas engine.

This gave us an inside look at electric powerboats' utility today and some clear ideas on electric boating's future.

PERFORMANCE

Electric power nearly matches gas at full throttle. Elco's EP-50 pushes the Boston Whaler to 27.9 mph while drawing 308 amps at 104 volts DC (32 kilowatts). Our tests show that the boat's 27 kilowatthours of usable battery power lasts for 51 minutes and covers 23.6 miles at that speed. Full throttle on the Johnson gas outboard averages 30.1 mph for 46 minutes, and it travels 23.9 miles from a 6-gallon tank of gasoline.

Slowing to the Whaler's sweet spot at near-23 mph, gas edges out the batteries, but it's close. The EP-50 runs for 81 minutes and travels 30.2 miles, while the Johnson goes for 94 minutes and travels 35.9 miles.

PROJECT INSIGHTS

Back in 2017, we started with Elco's 48-volt EP-30, intended to replace gas outboards in the 20 to 30 hp range. But with 296 pounds of lithiumiron-phosphate providing just 12 kWh of usable battery power, the boat lacked adequate range and wouldn't stay on plane with added people and gear.

During the following few years, we trialed different Elco motors mated to everevolving battery technology. Each iteration proved better than the last.