On the roof of the 4 Story Building, there will be solar panels with sun tracking feature. The sun tracking will double the solar hours I will have, and make the most of the panels. I will also have LED lighting, and Energy Star appliances. Everything in the building will be built around efficiency, and I will expect the same from my tenant below me. With all of that said, I would expect that the solar panels will pay for the electric bill, and maybe get a credit which can apply in the winter months where there are so few solar hours available.