Cohousing-L Mailing List: GeoSource Heating & Cooling Systems

[Merlin Porter-Borden (merlpb]

There is an industry supported group in Washington, DC, called the
Geothermal Heat Pump Consortium. Their job is to promote the development
of the new Geothermal, Earthsource, heating and cooling system which
will replace every other form of heating and cooling. The consortium
provides training, information, teleconferences (one held on Residential
Geosource Systems April 3, 1997), and they are actively engaged in
supporting Power companies to get into the act. The company supporting
the WDC area is offering LARGE rebates to individuals who install GSHP.

The initial cost is $2-5K higher than conventional systems in new
houses; HOWEVER, the increase in a mortgage is less than the savings
from energy cost (up to 60% heating & 40% cooling cost saving). Payoff
is running 3.5 to 4.5 years (initial cost differential vs savings on
energy). The heat exchange unit works like your refrigerator (quiet),
can be installed in a crawl space or basement or closet (not outdoors),
has a maintainance rate less than half a conventional system. The
heat/cooling medium is the Mother Earth: install a closed (prefer) or
open loop in a bore hole using the constant 55 degree water temperature,
or there are several configurations of ground loops at 8-10 feet deep
(helix loop plastic pipe in a tench.  The conditions dictate (design),
but a typical home might have a 450 ft bore hole. You can get water
heated, too; especially efficient in the summer, when you are dumping
heat back into the earth.

A minimum cost setup would be forced air. Better and costlier would be
forced air cooling and baseboard water or radient floor heating (can't
cool any other way, practically, that I know of). 

We at Liberty Village are planning to use this system. Our duplexes may
have one bore hole and an exchanger in each side. Our Common House and
Pool (future) will probably be serviced by a ground loop system under
the parking lot or Village Green. Personally, I'm planning a heated
basement floor (Cathie's studio), and baseboard water, if we can afford
the option. If we were not moving into cohousing, since our system is
due for upgrade, I would be installing this geosource system. this
system is proven and VERY GREEN.

GPHC is at www.ghpc.org

Merlin Porter-Borden, Liberty Village, Maryland, 35 mi fm Baltimore and
55 from WDC, digging dirt soon for 35 homes and 4 detached lots, 19
vested partners/homeowners.