Comment by yostrovs

You seem to be missing the human element in your calculation. It's not just power plants and the machines that use the electricity from them. The machines are built for humans, who want their clothes washed today so they can be folded today and ready for tomorrow. They want the dishes washed today so they can be put back on the shelves before tomorrow's breakfast. And, by the way, grime on dishes gets more difficult to remove once it has sat drying, waiting for the machine to start.