From ReVision Energy

RYE – On Saturday October 3rd Seacoast residents will get a chance to see two of renewable energy’s lead players working together – geothermal and solar electric. The house, located on Grove Rd. in Rye will be open all day long as part of New Hampshire Sustainable Energy Association’s state-wide green tours. The residence featured in this open-house has a four-ton ground-source geothermal system which uses naturally stable underground temperatures to run at a very high efficiency, compared to resistive electric heating. But as a “renewable” technology this large heat pump, (something required of all geothermal systems) is only as green as the extra kilowatt hours it takes from the grid. Home-owners Michele and Marc Sopher considered the limitations of geothermal and it’s dependence on electricity while designing their home, and so incorporated both geothermal and solar photovoltaics (PV) into the building. This dual renewable approach allows the on-site solar panels to power the heating system, and makes a real bid for a fossil-free building.

The new construction features materials that are efficient, of sustainable origin, and non-toxic. Very high insulation levels of R60 (ceiling) and R40 (walls) help insure minimum heat escapes during the cold New England winter. Appliances, windows and doors were selected to Energy Star criteria, and the house itself is expected to receive the Energy Star rating soon.

Pat Coon and Will Kessler of ReVision Energy partnered with the Sophers to determine the best use of the house’s excellent southern exposure. “We took a look at the existing system, and it just made sense. With the geothermal pump’s electric load, solar PV is a real dovetail,” says Kessler. The system consists of eighteen Evergreen panels, and will produce around 380 kWh monthly, with an annual CO2 savings of around 7,000 lbs. Installed in 2009, the solar system is positioned to take advantage of both the uncapped 30% federal tax credits and the $6,000 state rebates offered by the New Hampshire Public Utility Commission.

In order to track the gross renewable power generated on site, ReVision Energy installed a separate meter adjacent to the DC/AC inverter. It turns out that PSNH’s primary meter is bi-directional, and so when the panel’s electric production exceeds demand, the extra kilowatt-hours are banked under the NH Net Metering Program. Says Mrs. Sopher: “It is very gratifying to see the meter outside spinning backward!”

For more information, see the Sopher House property listing on New Hampshire Sustainable Energy Association’s Green Buildings Open House page by clicking www.nhsea.org/resource/gboh_detail.php?h_id=142. The open house runs from 10-4PM on Saturday, October 3.