Direct Utilization of Geothermal Energy 2015 Worldwide Review

Abstract

This paper presents a review of the worldwide applications of geothermal energy for direct utilization, and updates the previous survey carried out in 2010. As in previous reports, an effort is made to include and quantify ground-source (geothermal) heat pump data. The present report is based on country update papers prepared for WGC2015 and other sources of data available to the authors. Final update papers were received from 80 countries of which 70 reported some direct utilization of geothermal energy. An estimate of the installed thermal power for direct utilization at the end of 2014 is 60,000 MWt, almost a 20% increase over the 2010 data, growing at a compound rate of 5,0% annually with a capacity factor of 0.30. The thermal energy used is 500,000 TJ/year (125,000 GWh/yr), about a 20% increase over 2010, growing at a compound rate of 5.0% annually. The distribution of thermal energy used by category is approximately 45% for ground-source heat pumps, 25% for bathing and swimming (including balneology), 15% for space heating (of which 85%% is for district heating), 6.0% for greenhouses and open ground heating, 3.0% for industrial process heating, 3.0% for aquaculture pond and raceway heating, 1.0% for agricultural dryings, 1.0% for snow melting and cooling, and 1.0% for other uses. Energy savings amounted to 300 million barrels (45 million tonnes) of equivalent oil annually, preventing 38 million tonnes of carbon and 120 million tonnes of CO2 being released to the atmosphere, including savings from geothermal heat pumps in the cooling mode (compared to using fuel oil to general electricity).