Sparky's hull was designed to operate efficiently at displacement speeds (under about 10 mph). She has a long waterline and relatively modest beam for her size. The underwater shape permits her to slip easily through the water leaving little wake. The cedar strip/ fiberglass sandwich construction is strong, watertight and lightweight. The complete boat, including 530 lbs. of batteries, weighs only 1720 lbs. The modern brushless electric motor works efficiently at a wide range of speeds. These factors combine to give Sparky a remarkable combination of speed and range. Sparky is capable of going 40 miles at 7 mph using 80% of the battery capacity. That's almost 6 hours of cruising; slow down to 5 mph and the range doubles. Range at the top speed of 8.5 mph is about 15 miles. The hull shape is so efficient that 1 hp will drive this 25' boat 5.5 mph and 2 hp pushes her 7 mph. Efficiency implies low fuel cost. Sparky's light weight and slender round bilged hull make her very energy efficient and her electric propulsion system makes her very fuel-cost efficient as well. (An electric motor, with batteries recharged from the utility grid, can produce mechanical energy for about one-fourth the cost of producing the same mechanical energy with a gasoline engine. This assumes fuel costs of $0.10 kW-h and $3.50 per gallon.). The electric bill to recharge the batteries after that 40-mile cruise will be less than one dollar. That's like getting 140 miles per gallon in a gasoline powered craft! Another interesting comparison is that a typical 24' deep-V runabout will burn about $1.00 of gas per mile idling along at 7 mph. Sparky uses 2.5 cents worth of electricity.