Grum's little Leek gas engine is a beauty and operates on an interesting cycle..
With some care it could be developed into a linear hot gas piston cycle, ditch the rotary crank assembly.
hhop provides the capability to pump the coolant (hhop electrolyte) and therefore heat, around the loop using working fluid fuel pressure (water electrolyte).
The ignition function can be moved from hhop d/c chamber to hot gas piston chamber.. driving a secondary cold gas piston linear generator running on a refrigeration cycle from the heat produced.
hhop provides heat pump fluid transfer to heat exchanger to drive cold gas piston linear generator using an external combustion cycle function to drive the hot and cold gas piston linear axial cycles.
Everyman Standing Order 01: In the Face of Tyranny; Everybody Stands, Nobody Runs.
Everyman Standing Order 02: Everyman is Responsible for Energy and Security.
Everyman Standing Order 03: Everyman knows Timing is Critical in any Movement.