My friend built a 320 sq.ft. cabin up in the mountains. He ask me to design and build a solar power system for the cabin. I used a 5000 watt pure signwave inverter, charge controler, 8 6 volt golf cart batteries and 5 300 watt solar panels. Total price was about $5000. About the same as the connect price to the power coop. All this powers a small apartment frig, TV, celing fan and 5 lights.