I have idea for drastic increase in efficiency of low temperature differential (50*C) stirling engines, which would make liquid air storage a viable alternative

I have idea for drastic increase in efficiency of low temperature differential (50*C) stirling engines, which would make liquid air storage a viable alternative to grid scale batteries, super cheap solar-thermal panels could outcompete PV panels and it would alleviate problems with cooling large power plants while generating more energy from the same amount of fuel. The only problem - I didn't yet made a prototype to validate this idea, because I have to work overtime just to support myself and family. I'm slowly making progress on this and I will be able to finish that prototype until end of year.