This steam engine is so cheap that it, or something very much like it, will shut down most power plants and eliminate a lot of the grid:
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The actual thermodynamic cycle on a T-S chart is more or less elliptical -- 71% of the ideal Carnot rectangle.
Liquid piston is the only cheap way to isentropically expand steam and the only way whatsoever to isentropically compress low quality steam to saturation pressure/temperature.
For gas hybrid vehicles and other fuel situations the cycle efficiency can easily be improved to 95% Carnot -- something like 28% @ only 500 F.
Everyone thought a Carnot cycle engine was difficult to build when all it took was a couple of tubes and some water.
Bret Cahill