WHO: LuAnn Kuder and Maureen O'Brien

WHERE: Newbury

Kuder, 60, and O'Brien, 59, bought their circa-1950 home in Newbury 15 years ago, when they were indifferent to its outdated forced-air heating system, meager insulation, and lack of air conditioning. They were happy there-until the record-hot summer of 2006. Looking for an energy-efficient way to cool their sweltering home, O'Brien chanced upon an article in a local newspaper about geothermal systems, which use groundwater's stable temperatures to heat and cool homes. The couple soon hired a contractor to design and install just such a setup for them. To tap the earth's energy, they dug a 500-foot-deep well, then used a condenser to extract heat (in the winter) and cooled air (in the summer) from the 55-degree well water. Because the geothermal mechanics required more electricity to run than their old forced-air system, Kuder and O'Brien installed solar panels that produce enough electricity to sell some back to NStar. "We were planning on retiring here, so we wanted the house to be as comfortable and affordable as possible," Kuder says. "But we were also intent on doing something to help the environment." They've succeeded on all three counts, especially the comfort factor. "The thermostat stays between 68 and 75 degrees," says O'Brien. Adds Kuder, "It's so refreshing!"

The Setup

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