All current designs (except for the human-powered Shweeb) are powered by electricity. In order to reduce vehicle weight, power is generally transmitted via lineside conductors rather than using on-board batteries. According to the designer of Skyweb/Taxi2000, J. Edward Anderson, the lightest system is a linear induction motor (LIM) on the car, with a stationary conductive rail for both propulsion and braking. LIMs are used in a small number of rapid transit applications, but most designs use rotary motors. Most such systems retain a small on-board battery to reach the next stop after a power failure.