Power Considerations

If I've convinced you to add one or possibly two motors to your boat, Barry Stegall, product manager for Motorguide, maker of Great White saltwater electric trolling motors, suggests you buy the most powerful motor that you can afford. If possible, it should be a 36-volt model. Here's why: A 12-volt electric motor uses 1.2 amps per pound of thrust, a 24-volt uses .9 and a 36-volt uses .55. The 36-volt system is more than twice as efficient as the 12-volt. You'll go much, much longer between battery charges. Also, Stegall added that the more powerful motors can be run at a lower setting to provide the same thrust as a smaller motor, and they still have the reserve power to get you out of a tight spot.
I've also learned that while electric motors are relatively simple to install, the more powerful ones - and they now exceed 100 pounds of thrust - require some planning and at least a basic knowledge of electronics. My Suzuki outboard dealer, Portland Yacht Services, of Portland, Maine, was able to handle the wiring of the dual 24-volt motors, including the installation of quick-disconnect receptacles to facilitate removal. The lip on the transom of my Parker also required some minor modifications in order to provide a secure mount. All in all, though, installing and connecting the motors is not a problem. And, I found that if you get a bit confused, the factory support is readily available, competent, and usually free.