Turkey Geothermal Resource Assessment

Abstract

Turkey’s vast geothermal resources fall into two broad categories: hydrothermal and hot rock resources (EGS). All current geothermal exploration and development projects in Turkey are focused on hydrothermal. The geothermal potential and dependency on imported energy sources are stimulating geothermal energy exploration and development projects in Turkey.
To evaluate the potential of geothermal energy for Turkey, an assessment study has been underway by Istanbul Technical University. Our ongoing study focuses on estimating the potential of geothermal fields in terms of electricity generation and non-electric thermal production. We focus our efforts on two resource categories: (1) hydrothermal resources shallower than 3 km, and (2) geothermal potential of Turkey obtained using terrestrial heat flow. Our results so far reveal that the geothermal resource potential of rocks shallower than 3 km is 3±1x1023 J. Taking the results of the Monte Carlo Simulation studies for medium-to-high temperature geothermal (hydrothermal) fields (a total of 40 individual fields) as an estimate of the lower limit of the geothermal potential, the lower limit of Turkey geothermal potential for electricity generation is estimated to be 661 MWe and the corresponding value for direct use to be 18077 MWt, both values valid for P10 (Cumulative Probability of 0.1) for a reference temperature of 100 oC and 15 oC.
As of May 2009, the identified geothermal capacity of all geothermal occurrences discovered in Turkey has reached about 4800 MWt on a reference temperature of 15oC. The installed capacity is estimated about 80 MWe for electricity generation whereas the energy use is estimated to be 800 MWt for direct use and nearly 50 MWe for electricity generation. However, the ongoing field development projects, particularly for the electricity generation, are expected to increase those figures respectively in near future.
This paper describes the methodology and presents the updated results in terms of identified hydrothermal capacity, geothermal resource base, and EGS potential. Furthermore, the subsurface temperature distribution map at 500 m depth is discussed.