The wind is ferocious today. Even when you're inside it will suck the energy out of you. I have no ambition to go outside to start the generator, so the prototype will have to wait another day at least.
While I was heating up the coffee, my mind wandered to Amy's thermoelectric coffee machine. We have a small solar array, and an 800W power sucker is not in the energy budget.
The skygerator has been through many design changes. Before I had done the radiative cooling math, one of my first thoughts was to use an inefficient Peltier cooler between the radiator and the refrigerator coil. After I had done the math, I scratched that idea. Now that I can have a significant temperature difference almost all the time I had to wonder about using a thermocouple in a different way.
Solar power is neat as long as the sun is shining. Wind power is nifty as long as you have wind. What if we could do something with a much more available difference between the ambient temperature and the much colder effective sky temperature? That's where this thinking about thermocouple is going.
Solar power arrays are sized to balance how much sun is expected with how much power one expects to use and store. The process for sizing a wind power system has similar complications. With a heat sucking sky that is much more available, on many days you could produce power all day long.
The thermocouple might not be the way to go for this application. A Stirling engine might be more practical. In fact, if you fit an Alpha Stirling to a compound parabolic emitter it should work with or without direct sunlight and in the dark. Talk about green energy! I'll have to do the math, but there must be a way.