I’d heard a little bit about electric engines. But having relied on our 350-pound trusty 1969 Volvo MD2B iron genny for close to two years on a cruise from San Francisco to Charleston, I admit to being among the naysayers when it came to the idea. Despite a long litany of mechanical misadventures—an oil change that had inadvertently shot out hot oil over sail bags in California, a blown head gasket in Mexico, and an extensive repair in Florida that involved my cradling the piston in my hands—when the wind dies, for me that's always meant turning to internal combustion engines (oars aside), simply because there hasn’t been too much of a choice.
The trimaran had been essentially disassembled into five pieces, rebuilt, reassembled, painted, and now stood ready for her first voyage. "It was an expensive way to get a new boat, although in the end it was actually cheaper than buying new," said Ted Turner Jr. of the refitted vessel that is now the flagship of his new boatyard. Originally designed for transatlantic races, Troika is 14 years old, and the major work done to her—reinforced floats and bulkheads, new sails, and power plant—are likely to see her through plenty of sailing seasons to come.
So what powers the batteries, you ask? A variety of things can serve to keep the batteries up to charge. On cruising boats, solar panels and a wind generator can contribute to keeping the motor running if need be. On Troika, a performance-oriented trimaran, a Panda 4KW generator ensures that the voltage never falls below a critical level. The generator uses a quart of diesel an hour, and automatically kicks should the voltage fall below 11.4 and shuts off after charging. The generator also has its own starting battery.
"In theory, you can keep the boat at the dock and it should take care of itself," said Spence. Additionally, since the configuration of the batteries means there is no need for a shorepower plug, you can just plug it into a 110 volts. "We think if we were motoring for 24 hours, the generator would run for about half that time."
Even when motorsailing, the system can discern the difference between motoring up a wave and surfing down it, and transfer energy to the battery banks. The engine is also more efficient when it comes to horsepower ratings. Inboard combustion engines usually have all sorts of horsepower-robbing pumps, compressors, and alternators connected to the fly wheel by belts. The Electric Wheel side-steps these parasites, and with less energy lost via these and the transmission, the torque is directed where you want it, at the propeller. A 98-lb six-horsepower motor can replace a 20-to-30 horsepower motor, and a 10-horsepower electric model can replace a 30-to-40 horsepower engine.
"When it’s on you hear things you’ve never heard before," said Spence, who’s company is looking forward to installing more of these units in the future, "like the shaft in the cutless bearing, and the prop spinning, which is ordinarily drowned out by the engine." And with no transmission, one can shift from full forward to full reverse without a pause.
The Electrical Wheel is available to fit the engine mounts of several types of engines. But it’s not something the average person would be able to drop in themselves. There’s a lot more circuitry, according to Spence, and alignment concerns remain the same, although vibration is more of a whirring nature and less of a chunk-chunking. You’re not likely to be able to take it apart and repair it, if some kind of glitch in its 80,000 to 100,000 maintenance-free design life does crop up while you’re marooned on a South Pacific island. So how much for one of these gizmos? Spence estimates about $5,000 in labor, $9,200 for the generator, $8,000 for the electric motor. And while those numbers might initially seem daunting, you could expect to drop something in that neighborhood for a diesel engine and generator if you were repowering your boat, and still have exhaust fumes, noise, and a fossil fuel mentality.
Going to the Source
The manufacturer of the Electric Wheel claims a lifespan three times greater than that of the average diesel engine. Twenty-three electric wheels are currently (no pun intended) whirring along in mono and multihulls ranging from 24 feet to 50 feet. Optimum performance of the Electric Wheel is achieved with a 144-volt system, typically fueled by twelve 12-volt batteries. Currently Group 27, 31 or 4D batteries are being used. The life cycle of batteries is dependent on their use, and when properly maintained, the life cycles of the batteries exceeding five years can be achieved, according to the company’s website. The average installation takes about five days, not including a day or two to remove the old engine and spruce up the engine room, and silent power is warranted for five years. For more information see www.solomontechnologies.com.
Electrical Work Rules by Don Casey
A Little Help from the Sun by Don Casey
Choosing and Installing Solar Panels by Sue and Larry