Architect Rob Whitten designed the Fullers’ house as
though it were going to have propane-fired radiant
heating, but the Fullers spent the winter the house was
being built investigating alternatives such as air-sourced heat pumps and geothermal systems.
“We decided low-velocity forced-air geothermal
was right,” says Steve Fuller.
A 210-foot well behind the house brings
groundwater to a Bosch geothermal heat pump in the
basement, which extracts heat from the water in a
process akin to refrigeration in reverse.
“Geothermal was approximately 10 percent more
expensive than the base-line propane radiant system,”
wrote Fuller in his A House in a Field blog, “but when
you consider the 30 percent tax benefit, the savings are
substantial. Now factor in the annual estimated
heating cost — $810 per year for the geothermal
system — and it was a no-brainer.”
In fact, “Our heating bills for the two winters we’ve
been here have actually been between $500 and $600
for the additional electricity,” says Fuller.
The low-velocity system means the house is quiet,
free from drafts, and maintains a constant comfortable
“Maine is a great place for geothermal,” says Fuller,
“because it’s all rock and clay. Geothermal doesn’t like
sand at all.”
design decision To Geo or Not to Geo