Geo-Heat Center
- Information for the prospective owner from the Oregon Institute of Technology. Includes technology background, terminology and description of various mechanisms.
- http://geoheat.oit.edu/

Wikipedia: Heat Pump
- Free encyclopedia article covering the technology basics. Addresses background, thermodynamic aspects for different types of heat pumps.
- http://en.wikipedia.org/wiki/Heat_pumps

European Heat Pump Association (EHPA)
- Non-profit organisation which promotes awareness and proper deployment of the technology in Europe. Includes basics, news, publications, events calendar, project and regulatory information.
- http://www.ehpa.org/

Geothermal Heat Pump Systems
- Describes the concept with animated graphics. Addresses installation concepts and mechanisms.
- http://www.geothermal-heat-pump-resource.org

Geothermal Heat Pump Energy - How It Works
- Explanation of the technology basics. Addresses heat extraction technic and mechanisms.
- http://www.geothermalheatpump.com/how.htm

Geoexchange
- Information on the technology from the U.S. Geothermal Heat Pump Consortium. Includes detailed case studies of applications, publications, statistics and facts.
- http://www.geoexchange.org/

Canadian GeoExchange Coalition
- Coordinates private and public sector stakeholders to inform, develop and promote products and services. Includes mission statement, membership and technological information. [English, French]
- http://www.geo-exchange.ca/

Geothermal Heat Pumps
- Technical fact sheet about the benefits of residential systems. Includes technical background and installation concepts.
- http://www.bchydro.com/powersmart/elibrary/elibrary685.html

Earth Energy Society of Canada (EESC/SCES)
- Information about the technology from the EESC. Includes technological backgrounds, ecological impacts and links to suppliers.
- http://www.earthenergy.ca/

International Ground Source Heat Pump Association (IGSHPA)
- Promotes the use of the technology worldwide through education and communication. Includes technical and commercial aspects, case studies, publications and conference calendar.
- http://www.igshpa.okstate.edu/

International Energy Agency (IEA) Heat Pump Centre
- Information from the IEA about the technology, applications and markets. Includes FAQs, research profiles and reports, announcements of conferences and events and links.
- http://www.heatpumpcentre.org/