Thermoelectricity

Thermoelectricity is the conversion from heat differentials to electricity or vice versa.

Batteryless radio

Thermoelectricity was widely used in the remote parts of the Soviet Union from the 1920s to power radios. The equipment comprised some bi-metal rods, one end of which could be inserted into the fireplace to get hot with the other end left out in the cold.

Related Topics:
Soviet Union - 1920s - Bi-metal

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Another way of achieving the same function is a Clockwork radio.

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