Electric Bicycles: A Guide to Design and Use (repost)

Design or build a battery-powered electric bicycle
For much of the world, bicycles are a transportation mainstay. Electric bicycles–powered by a rechargeable battery pack–are proven to deliver the highest possible energy efficiency, even compared to pedal bikes. A transportation alternative to fossil fuels, electric bicycles are fast catching on, in part because they don't require factory assembly. End-users can easily construct them with available components.