My winter project last year was to research and build an electric-powered bicycle, or ebike, to commute to and from Orono, about 10 miles each way. Of course, this project was inspired by the rising gas prices and the desire to commute in a cheaper, “greener” way:
• Sure, there is the BAT bus, but using that would require planning my appointments and meetings to fit the bus schedule, which sometimes does not work. This is a great option, just the same.
• Then there is the car, which gets about 22 mpg on a good day, has heated seats, and is great in the snow.
• Finally there is the motorcycle, and that gets a respectable 45 mpg.
The e-bike is about not using gasoline-powered transportation and finding another alternative energy-powered way to improve my carbon footprint during my daily commute to work.
The ebike project began with online research. I found an ebook written by an individual who built a high-performance ebike for commuting. He lives in Canada and has a 10-mile commute. Since I also had a 10-mile commute and lived in a hopefully warmer climate, I thought he had a good plan that fit my needs. I studied his ebook and fashioned my ebike project after his design.
From eBay I bought a used mountain bike, a Canadian brand Norco Charger. I sought a strong mountain bike frame. When I received the bike, it had a big dent in the top tube; this was repaired by welding the frame.
I then had the frame powder-coated Charger Blue.
Other basic parts included a brushless hub motor, the controller, and the batteries. The rear hub motor is the rear wheel, and it comes with spokes laced in a 26-inch wheel. I purchased durable parts, including the tires and the tubes, to help reduce flats and take the extra weight of the rear hub motor.
The controller is the brains of the operation, and the batteries are the power supply. I used lithium phosphate batteries, which claim good efficiency and long life (2000 charges). The batteries were run in series to make a 72-volt, 15-amp hour system capable of powering my commute.
Seeking help in assembling the ebike and its electrical components, I turned to the students at the University of Maine College of Engineering, where I work. They assisted me, Bangor Ski Rack technicians checked the ebike’s mechanical reliability, and Terry Jason (who has built an ebike) built the battery box and assembled the bike.
During my commutes from Bangor to Orono, the ebike makes the 10-mile trip in 22-25 minutes, not that different from using my car or motorcycle. I can avoid traffic jams by using the bike lane, and I can park the bike outside my office — and I don’t need a UMaine parking permit.
I spent about $1,500 a year in gas with my car. Building the ebike cost me about that much, and I calculate that if I ride the bike six months a year, the bike will pay for itself in two years.
Charging for the ebike for 1.5 hours costs about $0.15.