We’ve previously covered kerosene-powered radios, but the December 1939 issue of National Radio News covers a similar concept. Apparently, there were radios that were powered a home’s natural gas supply. This item is lacking in details, but it appears there were at least two such sets. One was somewhere in Britain, and the other one was displayed at the New York World’s Fair.

Like the kerosene sets, electricity came from a thermocouple.  The British version ran the filaments directly off the thermocouple, and the voltage was stepped up to provide the B+.