Fort Polk Installation Demonstrates Retrofi t Potential of Geothermal Heat Pumps
A recent independent study prepared for the U.S. Department of
Energy by Oak Ridge National Laboratory (Hughes, et al, 1998)
demonstrates that geothermal heat pumps (GHPs) provide substantial
benefi ts to the end user, the electric utility industry and the
environment. A comprehensive 4,003-home retrofi t project was conducted
at Fort Polk, Louisiana where the existing heating and cooling systems
(560 gas furnace/electric air-conditioner systems and 3443 air-source
heat pump systems) were replaced by GHPs with desuperheater water
heaters. In addition existing incandescent lighting fi xtures were
replaced by high-effi ciency fl uorescent or compact fl uorescent fi
xtures, and existing shower heads were replaced by low-fl ow shower
heads. Evaluation of this massive retrofi t showed that it reduced
electrical consumption in the 4003 residences by 26 million kWh (33%)
while altogether eliminating consumption of 27,425,000 MJ of natural
gas. Peak demand was reduced by 7.5 MW (43%), and the power factor was
increased from 0.52 to 0.62 . Emissions of CO2 have been reduced by an
estimated 20,321,000 kg per year at the Ft Polk site. The GHPs alone are
credited with 66% of the electricity savings and all of the natural gas
savings (Hughes and Shonder, 1998) accounting for about 14,900,000 kg of
the total annual CO2 emissions reduction
Retrofit Heat Pumps for Building
In the majority of European
countries, the present heat pump market for space and water heating and
cooling is largely concentrated on new buildings, particularly single
and two-family houses. However, there is a very large potential in the
retrofi t market for replacement of old conventional oil-, gas- and
coal-fired heating systems with high energy-efficient and
environmentally sound heat pumps