Bob-
I don't have the exact electrical usage, but can tell you this. Last summer I shut down the boiler and heated our hot water with the electric hot water heater in the cabin and my electric bill was much higher 30-40 dollars) than the summer before when used the boiler for heating the domestic hot water. If I had to guess, it probably uses around $30 a month in electricity. By the way, our electrical rates are pretty high up here.
-John