Stirling Engine was taken notice again, when PHILIPS Corporation started to research on Stirling engine as the power source of portable generator in about 1940. A 200 W Class Stirling engine was completed in about 1950. But the engine was not spread, because the transistor that can work at low power was invented.
I took this picture in 6th International Stirling Engine Conference,
Eindhoven (the Netherlands) on 1993.