John W. Lund1
(1) Geo-Heat Center, Oregon Institute of Technology, Klamath Falls, OR
Abstract: Direct-Use of Geothermal Energy
Direct-use of geothermal energy consists of various forms for heating and cooling. The major areas of direct-use are (1) swimming, bathing and balneology, (2) space heating and cooling including district energy systems, (3) agriculture applications, (4) aquaculture applications, (5) industrial processes including crop drying, and (5) geothermal heat pumps. Major direct utilization projects exploiting geothermal energy exist in over 40 countries, and the estimated installed thermal power is 9,000 MWt utilizing 37,000 kg/s of fluid. The worldwide thermal energy use is estimated to be 115,000 TJ/yr (32,000 GWh/yr). The majority of this energy use is for space heating (33%), and swimming and bathing (19%). In the USA, the installed thermal power is 2,630 MWt, and the annual energy use is 19,000 TJ (5,300 GWh). The majority of the use (60%) is for geothermal heat pumps (both ground coupled and water source), with space heating, bathing and swimming, and fish and animal farming each supplying about 10%. The USA, China and Iceland are the countries that have the largest amount of direct-use energy supplied by geothermal resources.
AAPG Search and Discovery Article #90914©2000 AAPG Annual Convention, New Orleans, Louisiana