How about giant capacitors (multiple) that can store power for clean usage later. Like if you have production turned off, and a windmill and soloar panel, you can save it up for a burst of energy later but clean.
A limited number of power-free productions could be charged! awesome cool.. I think I'll make them out of lots of aluminum.
gah, that means I have to render a big capacitor-y thing. Oh well it can basically be a box.
Then I'll have to revamp the power selection catagory.. use capacitor, use only environmentally-clean energy, use free power AND only coal or only reactor.. and use all power in the usual order. It's drop down time baby.
Capacitors come in a lot of shapes. In essence they're just parallel plates with opposite charges. Commonly they look like jelly rolls because they can be coiled up to get a lot of area in a small space.
I see this working almost like hull, where you can theoretically get as many as you want, but the price of each capacitor increases.
Would there be a way to drive more energy into the capacitor at limited efficentcy (2 fuel into 1 charge)? Would there be something that required a lot of power at once? Oh! That gives me an idea.. *starts another topic*