Groundwater Heat Pump System Efficiency Measurements
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Compare COP's and EER's of groundwater heat pump systems
Ground coupled heat pump system efficiency measurements
Groundwater source heat pump systems & thermogeology
Books on geothermal heat pumps
Solar Age Magazine Articles on Renewable Energy, Energy Savings, Construction Practices
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This article discusses efficiency measurements of ground coupled heat pump systems: COP's and EER's. Accompanying text reprinted/adapted/excerpted with permission from Solar Age Magazine - editor Steven Bliss.
Also see our list of heat pump inspection, diagnosis, and repair articles beginning at HEAT PUMPS. CONTACT us to suggest text changes and additions and, if you wish, to receive online listing and credit for that contribution.
The link to the original Q&A article in PDF form immediately below is followed by an expanded/updated online version of this article.
Q&A on Groundwater Heat Pumps - original PDF version, use your browser's back button to return to this page. Solar Age Magazine, September 1986.
The question-and-answer article below paraphrases, quotes-from, updates, and comments an original article from Solar Age Magazine and written by Steven Bliss.
Groundwater Heat Pumps: confused about COPs and EERs
Question:
Several well-water heat pump manufacturers claim COP's of 3 to 6 and EER's of 13 to 17 [1986 data].
You can't tell which COP and EER measurement for groundwater based heat pump systems is "right" without additional data describing the testing conditions, according to Atlanta-based engineer Don Abrams, author of "Ground Coupled Heat Pumps" [Solar Age Magazine, Sept. 1985].
The building's heating and cooling loads and incoming water temperature all affect the efficiency measurements of the heat pump system.
Another factor affecting measurement of a ground-coupled heat pump system's efficiency is the energy required to pump the water. this could, by itself, account for the groundwater heat pump efficiency measurement differences on the order reported in your question above.
ARI engineer David Feron says that for groundwater-source heat pump efficiencies to compare with ARI figures, testing has to be done in accordance with ARI [now AHRI, Air-Conditioning, Heating, and Refrigeration Institute] standard 325-85.
[Note: as of 2011 AHRI publishes the following standards for Water-Source & Ground Water-Source Heat Pumps]
AHRI 410-2001: Forced-Circulation Air-Cooling and Air-Heating Coils
The question-and-answer article about heat pumps, quotes-from, updates, and comments an original article from Solar Age Magazine and written by Steven Bliss. Adapted with permission. January 2011.
Current references on ground and ground water source heat pumps:
Geothermal HVAC, [Amazon.com] Jay Egg & Brian Howard, McGraw-Hill Professional; ISBN-10: 0071746102, ISBN-13: 978-0071746106, quoting:
This definitive guide covers commercial and residential geothermal heating, ventilation, and air conditioning technologies and explains how to take advantage of their money- and energy-saving features. Geothermal HVAC: Green Heating and Cooling reviews the array of choices currently available, offers market values for systems based on varying options and conditions, and describes how to pair the best systems for each application and budget. Whether you're a contractor or a consumer, you'll find out what you need to know to implement a geothermal HVAC system in a retrofit or new construction project, and start benefiting from this sustainable, affordable technology.
Geothermal Heat Pumps is the most comprehensive guide to the selection, design and installation of geothermal heat pumps available. This leading manual presents the most recent information and market developments in order to put any installer, engineer or architect in the position to design, select and install a domestic geothermal heat pump system. Internationally respected expert Karl Ochsner presents the reasons to use heat pumps, introduces basic theory and reviews the wide variety of available heat pump models. Expertly reviewed and adapted for the most geographically broad application possible, the book offers the reader valuable tips for planning and system control using data, graphics and tables from a growing and innovative market.
Readers will learn how heat pumps are able to extract heat from relatively low temperature water circulating in ground loops and raise it to a temperature high enough to heat a home. They will also learn how to estimate the size of the heat pump required and the ground loop size as well for straight 2-pipe, 4-pipe, 6-pipe and Slinky loop configurations. This is important in order to verify that the installer correctly sizes the system. Both horizontal and vertical loop systems, for GX and DX, are covered.
Some of the technical issues that are addressed include: Loop water flow rates and Reynolds Number, heat of extraction/rejection, heating capacity, desuperheater setup, open-loop/closed-loop, SCW, pond loops, DX, Manual-J, COP. The final chapter consists of a set of flowcharts guiding the homeowner to ask the pertinent questions needed for a successful installation.
Watch out, the geothermal and groundwater source heat pump articles just below are ridiculously expensive documents also available at Amazon.com.
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Solar Age Magazine was the official publication of the American Solar Energy Society. The contemporary solar energy magazine associated with the Society is Solar Today. "Established in 1954, the nonprofit American Solar Energy Society (ASES) is the nation's leading association of solar professionals & advocates. Our mission is to inspire an era of energy innovation and speed the transition to a sustainable energy economy. We advance education, research and policy. Leading for more than 50 years.
ASES leads national efforts to increase the use of solar energy, energy efficiency and other sustainable technologies in the U.S. We publish the award-winning SOLAR TODAY magazine, organize and present the ASES National Solar Conference and lead the ASES National Solar Tour – the largest grassroots solar event in the world."
Steven Bliss served as editorial director and co-publisher of The Journal of Light Construction for 16 years and previously as building technology editor for Progressive Builder and Solar Age magazines. He worked in the building trades as a carpenter and design/build contractor for more than ten years and holds a masters degree from the Harvard Graduate School of Education.
Excerpts from his recent book, Best Practices Guide to Residential Construction, Wiley (November 18, 2005) ISBN-10: 0471648361, ISBN-13: 978-0471648369, appear throughout this website, with permission and courtesy of Wiley & Sons. Best Practices Guide is available from the publisher, J. Wiley & Sons, and also at Amazon.com.
Excerpts with updates and annotations expanding the original Best Practices Guide text can be found in the online review and book summary at BEST CONSTRUCTION PRACTICES GUIDE and also at DECK & PORCH CONSTRUCTION, at INDOOR AIR QUALITY IMPROVEMENT GUIDE, and in other articles found at InspectAPedia.com such as HOUSEWRAP AIR & VAPOR BARRIERS, SOUND CONTROL in buildings, and other topics.
Air Conditioning and Refrigeration Institute, now the Air-Conditioning, Heating, and Refrigeration Institute, (AHRI), 2111 Wilson Blvd, Suite 500, Arlington, VA 22201, USA, Tel: 703.524.8800,
E-mail: ahri@ahrinet.org. Quoting from AHRI:
The Air-Conditioning, Heating, and Refrigeration Institute (AHRI) is the trade association representing manufacturers of air conditioning, heating and commercial refrigeration equipment. AHRI’s 300+ member companies account for more than 90 percent of the residential and commercial air conditioning, space heating, water heating, and commercial refrigeration equipment manufactured and sold in North America.
AHRI Standards can be downloaded at no charge from http://www.ahrinet.org/Content/FindaStandard_218.aspx
Geothermal HVAC, [Amazon.com] Jay Egg & Brian Howard, McGraw-Hill Professional; ISBN-10: 0071746102, ISBN-13: 978-0071746106, quoting:
This definitive guide covers commercial and residential geothermal heating, ventilation, and air conditioning technologies and explains how to take advantage of their money- and energy-saving features. Geothermal HVAC: Green Heating and Cooling reviews the array of choices currently available, offers market values for systems based on varying options and conditions, and describes how to pair the best systems for each application and budget. Whether you're a contractor or a consumer, you'll find out what you need to know to implement a geothermal HVAC system in a retrofit or new construction project, and start benefiting from this sustainable, affordable technology.
Geothermal Heat Pumps is the most comprehensive guide to the selection, design and installation of geothermal heat pumps available. This leading manual presents the most recent information and market developments in order to put any installer, engineer or architect in the position to design, select and install a domestic geothermal heat pump system. Internationally respected expert Karl Ochsner presents the reasons to use heat pumps, introduces basic theory and reviews the wide variety of available heat pump models. Expertly reviewed and adapted for the most geographically broad application possible, the book offers the reader valuable tips for planning and system control using data, graphics and tables from a growing and innovative market.
Readers will learn how heat pumps are able to extract heat from relatively low temperature water circulating in ground loops and raise it to a temperature high enough to heat a home. They will also learn how to estimate the size of the heat pump required and the ground loop size as well for straight 2-pipe, 4-pipe, 6-pipe and Slinky loop configurations. This is important in order to verify that the installer correctly sizes the system. Both horizontal and vertical loop systems, for GX and DX, are covered.
Some of the technical issues that are addressed include: Loop water flow rates and Reynolds Number, heat of extraction/rejection, heating capacity, desuperheater setup, open-loop/closed-loop, SCW, pond loops, DX, Manual-J, COP. The final chapter consists of a set of flowcharts guiding the homeowner to ask the pertinent questions needed for a successful installation.
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