Abstract: Ground water is attractive as a potential low-temperature energy source in residential and commercial space-conditioning
applications. When used in conjunction with a heat pump, ground water can serve as both a heat source (for heating) and a heat sink (for cooling).
The temperature of the ground water varies little, if at all, on a seasonal basis, regardless of the temperature extremes on the surface.
Thus, it is warmer than the outside air in winter and cooler in summer. Since heat pump capacity and efficiency vary signficantly with
the heat source/sink temperature (or temperature difference between the source/sink and the conditioned space), a ground water-source heat
pump system should, in principle, offer considerable advantages over the more widely used air-source heat pump system.
However, the use of ground water (well water) is not without potential technical problems or economic and institutional constraints. First, is the
well cost and the availability of an adequate supply of sutiable quality well water. Second, the removal of significant quantities of well water without
suitable recharge may deplete the underground aquifer. Also, plans to reinject or return the water underground may be precluded by legal restrictions. And
if permitted, it could entail additional costs for the disposal well. Special provisions to prevent thermal alteration of the underground source may be
required. This study was designed to answer these and other questions related to:
- ground-water quality and availability
- potential environmental effects
- legal restrictions
- energy use and economics of ground-water heat pump use
Keywords: water source heat pump, ground water heat pump, energy efficiency
Availability:
National Technology Information Service
U.S. Department of Commerce
5285 Port Royal Road
Springfield, Virginia 22161
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