page_title: Geothermal heat pump
section_title: Ground heat exchanger
hierarchical_section_title: Geothermal heat pump / Ground heat exchanger
caption_attribution_description: English: Ground-coupled heat exchanger of a heat pump: loop field for a 12-ton system. Français&#160;: Exemple de système d'échangeur de chaleur à 12 lignes de boucle (de tuyauterie plastique) immergée dans un bassin. Le réseau de tuyaux est ici monté au sol, avant d'être coulé au fond d'une pièce d'eau rectangulaire, munie d'un lest de parpaings, pour être utilisé dans une installation de pompe à chaleur. En hiver des calories sont captées dans l'eau et en été ce sont les frigories qui sont valorisées. Ce système s'inspire de celui de puits canadien
context_page_description: A geothermal heat pump or ground source heat pump is a central heating and/or cooling system that transfers heat to or from the ground.
  It uses the earth all the time, without any intermittency, as a heat source or a heat sink. This design takes advantage of the moderate temperatures in the ground to boost efficiency and reduce the operational costs of heating and cooling systems, and may be combined with solar heating to form a geosolar system with even greater efficiency. They are also known by other names, including geoexchange, earth-coupled, earth energy systems. The engineering and scientific communities prefer the terms "geoexchange" or "ground source heat pumps" to avoid confusion with traditional geothermal power, which uses a high temperature heat source to generate electricity. Ground source heat pumps harvest heat absorbed at the Earth's surface from solar energy. The temperature in the ground below 6 metres is roughly equal to the local mean annual air temperature.
context_section_description: Heat pumps provide winter heating by extracting heat from a source and transferring it into a building. Heat can be extracted from any source, no matter how cold, but a warmer source allows higher efficiency. A ground source heat pump uses the top layer of the earth's crust as a source of heat, thus taking advantage of its seasonally moderated temperature.
  In the summer, the process can be reversed so the heat pump extracts heat from the building and transfers it to the ground. Transferring heat to a cooler space takes less energy, so the cooling efficiency of the heat pump gains benefits from the lower ground temperature.
  Ground source heat pumps employ a heat exchanger in contact with the ground or groundwater to extract or dissipate heat. This component accounts for anywhere from a fifth to half of the total system cost, and would be the most cumbersome part to repair or replace. Correctly sizing this component is necessary to assure long-term performance: the energy efficiency of the system improves with roughly 4% for every degree Celsius that is won through correct sizing, and the underground temperature balance must be maintained through proper design of the whole system. Incorrect design can result in the system freezing after a number of years or very inefficient system performance; thus accurate system design is critical to a successful system 
  Shallow 3–8-foot (0.91–2.44 m) horizontal heat exchangers experience seasonal temperature cycles due to solar gains and transmission losses to ambient air at ground level. These temperature cycles lag behind the seasons because of thermal inertia, so the heat exchanger will harvest heat deposited by the sun several months earlier, while being weighed down in late winter and spring, due to accumulated winter cold. Deep vertical systems 100–500 feet (30–152 m) deep rely on migration of heat from surrounding geology, unless they are recharged annually by solar recharge of the ground or exhaust heat from air conditioning systems.
  Several major design options are available for these, which are classified by fluid and layout. Direct exchange systems circulate refrigerant underground, closed loop systems use a mixture of anti-freeze and water, and open loop systems use natural groundwater.
caption: Loop field for a 12-ton of refrigeration/42 kW system (unusually large for most residential applications)
exif: {"Image ImageDescription": "HPIM0546.JPG", "Image Make": "Hewlett-Packard", "Image Model": "Photosmart M417", "Image Orientation": "Horizontal (normal)", "Image XResolution": "72", "Image YResolution": "72", "Image ResolutionUnit": "Pixels/Inch", "Image Software": "730_RF", "Image DateTime": "2006:10:24 14:56:36", "Image YCbCrPositioning": "Co-sited", "Image Copyright": "Copyright 2003-2004", "Image ExifOffset": "266", "Thumbnail Compression": "JPEG (old-style)", "Thumbnail XResolution": "72", "Thumbnail YResolution": "72", "Thumbnail ResolutionUnit": "Pixels/Inch", "Thumbnail JPEGInterchangeFormat": "18418", "Thumbnail JPEGInterchangeFormatLength": "13476", "EXIF ExposureTime": "1/108", "EXIF FNumber": "481/100", "EXIF ExposureProgram": "Program Normal", "EXIF ISOSpeedRatings": "100", "EXIF ExifVersion": "0220", "EXIF DateTimeOriginal": "2006:10:24 14:56:36", "EXIF DateTimeDigitized": "2006:10:24 14:56:36", "EXIF ComponentsConfiguration": "YCbCr", "EXIF CompressedBitsPerPixel": "110029/19200", "EXIF ShutterSpeedValue": "6759/1000", "EXIF ApertureValue": "1133/250", "EXIF ExposureBiasValue": "0", "EXIF MaxApertureValue": "1541/500", "EXIF SubjectDistance": "49/20", "EXIF MeteringMode": "Average", "EXIF LightSource": "Unknown", "EXIF Flash": "Flash did not fire, auto mode", "EXIF FocalLength": "25/4", "EXIF FlashPixVersion": "0100", "EXIF ColorSpace": "sRGB", "EXIF ExifImageWidth": "1280", "EXIF ExifImageLength": "960", "EXIF DigitalZoomRatio": "1", "EXIF GainControl": "110", "EXIF SceneCaptureType": "Standard", "EXIF Contrast": "Normal", "EXIF Saturation": "Normal", "EXIF Sharpness": "Hard", "EXIF SubjectDistanceRange": "3", "EXIF Tag 0xA421": "5", "EXIF Tag 0xA422": "[518, 52, 0, 0, 1031, 1035, 1041, 1048]", "EXIF Tag 0xA423": "b'\\x07\\x04\\x0b\\x04\\x11\\x04\\x18\\x04\\x1d\\x04%\\x04,\\x043\\x049\\x04=\\x04, ... ]", "EXIF Tag 0xA424": "e", "EXIF Tag 0xA425": "[723, 671, 1200, 2406, 753, 740, 835, 7597]", "EXIF Tag 0xA426": "[109, 0, 0, 0, 37, 22, 73, 255, 4, 113, 2, 1, 0, 9999, 113, 2, 3, 0, 27, 7, ... ]", "EXIF Tag 0xA427": "[]", "EXIF Tag 0xA428": "[]", "EXIF Tag 0xA429": "[113, 105, 0, 0, 28548, 2091, 9600, 248]", "EXIF Tag 0xA42A": "1", "EXIF Tag 0xA42B": "0", "EXIF Tag 0xA42C": "0", "EXIF Tag 0xA42D": "52", "EXIF Tag 0xA42E": "[]", "EXIF Tag 0xA42F": "1", "EXIF CameraOwnerName": "[0, 0, 0, 0, 0]", "EXIF BodySerialNumber": "104", "EXIF LensSpecification": "110", "EXIF LensMake": "0", "EXIF LensModel": "0", "EXIF LensSerialNumber": "37", "EXIF Tag 0xA436": "0", "EXIF Tag 0xA437": "0", "Interoperability InteroperabilityIndex": "R98", "Interoperability InteroperabilityVersion": "[48, 49, 48, 48]", "EXIF InteroperabilityOffset": "5942"}