Since installing my solar array a year ago, it has produced more than it was designed for! (10.5 megawatts instead of 9) This is really great.  We added an electric hot water heater so we could shut down the oil fired furnace in the summer that provided our hot water previously.  We have two mini splits that we used for heat on the shoulder months for warmth.  While the winter was not terribly cold we saved quite a bit of oil – we still turn the furnace on when it gets cold – and we did not even turn on our pellet stove.  We ran the hot tub all we wanted as well from late October until mid April.  All this electric use and we still have kWh in the “bank”.  We could add electric capacity if we needed to for more heaters or if we get a plug in car.  Bottom line is that we did not pay any electric bill (except for the $10.37 it costs to have a meter), saved probably 400 gallons of oil, and spent $0.00 on pellets for the stove.  I am aiming for a total energy saving payback of about 6 years – I think we are on track so mission accomplished!