ZEH-Richmond's performance at year's end

So we have had a solid, representative year in our house now and we wanted to update its real-life performance. Our total energy bill for 2011 was $954, $532 for electricity and $422 for natural gas. The electric bill reflected the cost for heating, cooling, lights, appliances, etc. The highest monthly bill was $125 in the winter, while five months (the "shoulder" seasons in the spring and fall) were effectively "zero". Our natural gas bill reflected energy used to heat water, cook and operate the gas fireplace. The highest bill was $55 in the winter, while the lowest was $20 in the summer. We did make thoughtful attempts to run the house in an energy efficient fashion, opening & closing windows to take advantage of natural heating and cooling effects, and maintaining temperatures of 69day/68night (the geothermal system does not like big heat swings) in the winter and 76-78 in the heat of the summer. Our SRECs have turned out to be a bust. The initial contract we signed got "lost" in the system, and the replacement contract was only offered at a variable auction rate. The bottom subsequently fell out of the SREC market due to regulatory and political decisions that are too complex to explain here. As a result, we received a nominal $80 this year for SRECs, putting our net annual energy bill at $874. Given we have Watersense rated water fixtures and low flow toilets in the house, it is worth adding that our total annual water & sewage bill was $714. The lowest monthly bill was $31 and the highest was $90 (fall replanted lawn irrigation effect).So in sum, our average monthly energy bills were $73, our average water & sewage bill was $59 and our average total monthly utility bill was $132. In comparison, the average monthly energy bill for a (smaller) US home was approximately $180. We didn't make "zero", for a number of reasons I will address in a later blog, but I feel that a monthly energy bill for about the price of a dinner and a movie for the two of us is a pretty fair result!

Zero Energy Home Virginia:Solar PV-show me the money!

Everyone is always curious about the cost of solar PV and its "payback". So here's the numbers in black and white. The 4.2kW system cost $30,973 installed. The Commonwealth of Virginia gave us a rebate of $7189, and the Feds will give us a tax credit of $7135, resulting in a net cost of $16,649. We are selling the SRECs (Solar Renewable Energy Credits) for $200/yr. each (thanks to Cory, from olddominioninnovations.com, for brokering this) , for a total of approximately $800-1000 per year. The panels are generating from 11-25kWh per sunny day (less right now, with the shorter days & the sun lower in the sky; more come the long, high-in-the-sky days of early summer). So there it is, in black & white. I will leave it to each of you to decide how the "payback" looks to you, as the ways of calculating it are as myriad as the colors in the rainbow! All I know is that I love watching the digits in the Dominion Power digital meter get smaller!