Bob, all hope is not lost. Using the small power source could still be done, just not dumping it into the mains. If you use an electric water cylinder, you could dump it continously into a heating element during the day and thereby reduce the amount of power consumed at night.
The simplest method that comes to mind is to generate DC to charge a UPS battery and then dump the UPS output into a heating element. A small UPS could power an electric kettle or toaster and a larger one could power a water cylinder element.
