I’ve got a similar one, yet to be written, about “cold computing”. How do you compute if you’re on a limited solar+battery installation? what if your CPU wakes

I’ve got a similar one, yet to be written, about “cold computing”. How do you compute if you’re on a limited solar+battery installation? what if your CPU wakes up and you have only a couple of hours of runtime? What if you only can turn on wifi for 20 minutes a day?