Ground-coupled heat pump system experimental results

Conference · Wed Jun 01 04:00:00 EDT 1983 · ASHRAE Trans.; (United States)

OSTI ID:6772338

Metz, P D

Since October 1980, a small house in Upton, Long Island, New York has been heated and cooled by a liquid-source heat pump using a shallow serpentine earth coil as a heat source/sink. This paper, introduces and describes the system, presents system performance data for the winter of 1981-82 and the summer of 1982, and discusses these results. The experimental test house is a 1120 ft/sup 2/ (104 m/sup 2/) three-bedroom ranch-style house of energy-saving construction with a heating load of 4.1 X 10/sup 3/ Btu//sup 0/F.day (7.8 X 10/sup 6/ J//sup 0/C.day). The heat pump used during most of the period reported on here is a commercially available water-to-air unit sized to just meet the building's design heating load with no auxiliary heat. The earth coil contains 507 ft (155 m) of nominal 1-1/2 in. (4 cm) medium-density polyethylene pipe and is buried 4 ft (1.2 m) deep. An antifreeze solution consisting of approximately 25% ethylene glycol in water is employed to permit subfreezing earth-coil operation. Two independent data acquisition systems, a datalogger-microcomputer system backed up by a Btu-meter, monitor the spaceconditioning system's performance. During the winter of 1981-82, the system, which extracted 14.7 X 10/sup 6/ Btu (15.5 X 10/sup 9/ J) of heat from the ground, operated with a seasonal performance factor (SPF) of 2.46. No resistance heating was used. The earth coil's minimum daily U-value observed during this season was 1.93 Btu/ft-hr-/sup 0/F (3.34 W/m/sup 0/C). During the summer of 1982, a total of 10.0 X 10/sup 6/ Btu (10.6 X 10/sup 9/ J) of heat was rejected to the ground. The system SPF was 1.91, with a minimum daily U-value of 2.04 Btu/ft-hr-/sup 0/F (3.53 W/m/sup 0/C).

• Research Organization: Brookhaven National Laboratory, Upton, NY
• OSTI ID: 6772338
• Report Number(s): CONF-830640-
• Conference Information: Journal Name: ASHRAE Trans.; (United States) Journal Volume: 89
• Country of Publication: United States
• Language: English

Related Subjects

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION
320101* -- Energy Conservation
Consumption
& Utilization-- Residential Buildings-- (-1987)
BUILDINGS
CHEMICAL COMPOSITION
COMPUTERS
COOLING SYSTEMS
DESIGN
EFFICIENCY
ELECTRIC COILS
ELECTRICAL EQUIPMENT
ELECTRONIC CIRCUITS
ENERGY CONSERVATION
ENERGY SYSTEMS
EQUIPMENT
FEDERAL REGION II
FLUIDS
GROUND SOURCE HEAT PUMPS
HEAT PUMPS
HEATING SYSTEMS
HOUSES
MICROELECTRONIC CIRCUITS
MICROPROCESSORS
MONITORING
NEW YORK
NORTH AMERICA
ORGANIC COMPOUNDS
ORGANIC POLYMERS
PERFORMANCE
PIPES
POLYETHYLENES
POLYMERS
POLYOLEFINS
RESIDENTIAL BUILDINGS
SEASONAL VARIATIONS
SYSTEMS ANALYSIS
THERMAL EFFICIENCY
USA
VARIATIONS
WORKING FLUIDS