Clockwork radio

A clockwork radio or windup radio is a radio that is powered by human muscle power rather than batteries or the electrical grid. In the most common arrangement, an internal electrical generator is run by a mainspring, which is wound by a hand crank on the case. Turning the crank winds the spring, and a full winding will allow several hours of operation.

Like other self-powered equipment, it is intended for camping, emergencies and for use in areas of the world where there is no electrical grid and replacement batteries are hard to obtain, such as in developing countries or remote settlements. It is also useful when it will not be used on a regular basis and batteries would deteriorate, such as at a vacation house or cabin.

Clockwork radios designed for emergency use often include flashlights, blinking emergency lights, and emergency sirens. They also may include multiple alternate power sources such as conventional or rechargeable batteries, auto cigarette lighter plugs, and solar cells.

History

Radios powered by handcranked generators are not new, but their market was previously seen as limited to emergency or military organizations. The modern clockwork radio was designed and patented in 1989 by British accountant Trevor Baylis as a response to the AIDS crisis. He envisioned it as a radio for use by poor people in developing countries without access to batteries. In 1996 he cofounded Baygen Power Industries (now Freeplay Energy PLC), which produced the first commercial model. The key to its design is the use of a constant velocity spring to store the potential energy.

See also

* Alternative technology
* Appropriate technology
* Batteryless radio
* Electrical generator
* Self-powered equipment