Today’s boat engines, gallon for gallon, emit more pollutants than vehicles on the road. As a result, the US Environmental Protection Agency introduced requirements for catalytic converters on inboard and stern-drive boats beginning in 2011. Many manufactures of personal watercraft initially switched to outboard propulsion and are now looking to electric motors as the next step.

Converting a boat from gasoline to electric is not as straightforward as dropping in a battery and motor from a car, though. Since boat drag increases with speed, the energy to move a boat through water is far greater than that required for an equivalent electric vehicle.

Arnold offers Arnon silicon steel, laminated magnets and carbon-fiber windings for electric motors that require higher efficiencies. Arnold’s non-grain oriented electrical steel (NGOES) is optimized by thickness and finish. Arnon silicon steel is frequently used for laminations in high speed, high-efficiency motors and generators. Whereas common laminations use thicknesses between 0.356mm and 0.813mm, Arnon 5 and Arnon 7 are thinner – at 0.127mm and 0.178mm respectively.

Arnon electrical steel has been shown to be particularly advantageous for higher-frequency motors and generators above 400Hz. In these designs, the thinner material offsets the less efficient effects of increased eddy currents and subsequent heat build-up. Using thin laminations of Arnon produces a more efficient unit and frees up design constraints by making it possible to fully enclose the motor without external cooling, for example.

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