Geothermal resource assessment in Korea

To estimate available geothermal energy and to construct temperature at depth maps in Korea, various geothermal data have been used. Those include 1560 thermal property data such as thermal conductivity, specific heat and density, 353 heat flow data, 54 surface temperature data, and 180 heat production data. In Korea, subsurface temperature ranges from 23.9 °C to 47.9 °C at a depth of 1 km, from 34.2 °C to 79.7 °C at 2 km, from 44.2 °C to 110.9 °C at 3 km, from 53.8 °C to 141.5 °C at 4 km, and from 63.1 °C to 171.6 °C at 5 km. The total available subsurface geothermal energy in Korea is 4.25 × 1021 J from surface to a depth of 1 km, 1.67 × 1022 J to 2 km, 3.72 × 1022 J to 3 km, 6.52 × 1022 J to 4 km, and 1.01 × 1023 J to 5 km. In particular, the southeastern part of Korea shows high temperatures at depths and so does high geothermal energy. If only 2% of geothermal resource from surface to a depth of 5 km is developed in Korea, energy from geothermal resources would be equivalent to about 200 times annual consumption of primary energy (∼2.33 × 108 TOE) in Korea in 2006.