A method is provided for interconnecting a single electrical heating element of a hot water heater to first and second AC electrical power sources. Typically, these first and second AC electrical power sources include a utility provided electrical power source and a renewable power source that generates AC power from DC power. The method includes operating a controller that selectively connects and disconnects the first and second power sources. If sufficient electrical power is available from the renewable power source, the utility provided electrical power source may be disconnected to preferentially utilize renewable energy.