Converting power to signals in a circuit network?

[rootdoom33]

Is there a way to convert how much power that a certain thing is producing or how much satisfaction/consumption into signals so like whenever a solarpanel is producing 0 kW then it would output a signal?

[siggboy]

Why do you want to do this? What is your application?

Maybe there's a better way to solve your problem, especially since it appears to be related to energy and accumulator charge...