| Abstract |
Geothermal heat pump (GHP) systems first became popular in the 1950s after the initial introduction of the technology at the Commonwealth Building in Portland, Oregon, in the U.S. Numerous replications of that system, dating from about the same time, can be found throughout the western United States, serving a number of commercial and institutional buildings and complexes. Another resurgence in the development of GHP systems came following the oil crises of the 1970s when fears over rising costs and the availability of energy drove developers to look to systems that used indigenous resources. First cost, although still important, took a back seat in comparison to many other factors. However, after nearly 50 years of use, geothermal heat pumps still make up only a small percentage of heating, ventilation, and air conditioning (HVAC) installations. A lack of information and understanding relative to capital, operating, and maintenance costs, appear to stand in the way of more universal acceptance of the technology. A number of recent analyses and research studies as well as a number of case studies have now begun to shed light on the economics of geothermal heat pump systems versus various other HVAC system alternatives. |