725 Forest St: Environmental Scorecard

We are still working on the final calculations here as our approach has evolved from 727 Forest St. We should have this page updated by the end of August 2007. These are the preliminary numbers which are subject to change.

722           Therms of natural gas saved relative to the 2004 IECC standard
3226         Kilowatt-hours generated by the solar electric (photovoltaic) system

$1,044      Estimated annual cost savings (@ $1 / therm, $0.10 / kwh)

In addition to the economic benefits from these energy savings, there are these environmental benefits which come free of charge:

1.5          Cars not driven (25 MPG for 12,000 miles per year), or
7             Tons of CO₂ not released into the atmosphere every year
1             Acre of tropical rain forest (in terms of carbon sequestration)

Another way of thinking of the economic benefits:

These financial savings are like getting a bond or certificate of deposit worth $22,322 that yields 6% per year and whose value is indexed to the retail cost of electricity and natural gas. If the blended cost of electricity and natural gas were to increase say 50% over the next 10 years this hypothetical bond or CD that is bundled with the house would be worth $33,483. The environmental benefits above are all gravy on top of these economic benefits.

Sources:

Energy Information Administration, 2001, www.eia.doe.gov,  Residential Energy Consumption Survey; US-Climate Technology Cooperation Gateway website www.usctcgateway.net, www.Xcelenergy.com, pre-construction Energy report done by EnergyLogic