I think it's mistake both from gameplay and simulationism viewpoint to separate heat and energy. Energy cells should produce just heat, then you use other elements to covert some of that heat into usable energy and safely dispose what you can't use.
Awesome, but a little to hard. Even original had lives. I recommend letting start from any level you reached. And make first (zeroth?) level much smaller (and with just one ghost) to throw player a bone.
Also, light spot staying when pellet is eaten looks shoddy.