In the 1950s, flywheel-powered buses, known as , were used in () and () and there is ongoing research to make flywheel systems that are smaller, lighter, cheaper and have a greater capacity. It is hoped that flywheel systems can replace conventional chemical batteries for mobile applications, such as for electric vehicles. Proposed flywh.
[pdf] A typical system consists of a flywheel supported by connected to a . The flywheel and sometimes motor–generator may be enclosed in a to reduce friction and energy loss. First-generation flywheel energy-storage systems use a large flywheel rotating on mechanical bearings. Newer systems use composite
[pdf] Flywheel energy storage systems are highly efficient, with energy conversion efficiencies ranging from 70% to 90%. However, the efficiency of a flywheel system can be affected by friction loss and other energy losses, such as those caused by the generator or motor.
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