They acutally had an episode where an electrician came out to the house, fixed things in his lab, and gave the parents the bill. The mom decided to pay in nickels though.
They went into the lab a few times. They always questioned him about it. The only episode that sticks out in my mind is when his family did a power rangers thing and got their own robot that would attach to each others making one giant robot.
Maybe he takes power directly from the city.