One of the most interesting off grid solar deals I have seen is the solar pool pump. It is a DC pump and runs with whatever the sun is putting out at the time. There are no batteries and a very rudimentary controller, only meant to protect the motor from an unusably low voltage.
You don't get "paid back" from the utility but you are not paying them to keep your pool blue so it is about the same.
That is the one I may end up with.
