We can see that a Stirling engine is a thermal solar power reciprocating piston engine that uses solar radiation to produce heat in place of traditional fossil fuels.
This highly efficient solar thermodynamic heating machine converts the temperature difference (thermal energy) into mechanical power (kinetic energy). The difference this time is that it uses a gas rather than steam to drive a piston. This results in a pressure change that is used to power a piston inside the engine cylinder in much the same way as a Rankine steam engine operates.
So the Stirling engine works by alternately heating and cooling of the gas by an external heat source, extracting energy from the gas’s expansion and contraction.
