30 May 2005

CO2 EMISSION REDUCTIONS FOR GEOTHERMAL HEAT PUMP SYSTEMS IN THE NORTHEAST AND MID-ATLANTIC UNITED STATES


Geothermal Heat Pump systems developed in the US largely because of the demand for space
cooling in single-family houses. About fifteen years ago geothermal heat pump systems with borehole
heat exchangers (BHE) were being applied to larger buildings. The motivation to reduce or avoid
greenhouse gas emissions has spurred geothermal technologies in the last ten plus years. To estimate the
impact of GHP installations on avoidance of CO2 emissions, nine commercial installations in New Jersey
were studied. In all cases emissions were reduced over a conventional system. If high efficiency GHP
systems were installed the avoided emissions were between 31% and 50% of a gas boiler/ cooling tower
system. These results are extrapolated for other similar climates with different fuel mixtures.