Opportunity and challenges in large-scale geothermal energy exploitation in China

Under the significant pressure to diversify energy supply and reduce the dependence on fossil fuels, harnessing the vast geothermal resources has been made a priority in China's renewable energy development plans. This review provided an overview on the development of geothermal power generation and direct use in China, identified the key barriers for geothermal energy utilization, particularly in power generation, and proposed corresponding measures for boosting the growth of geothermal industry. Little progress was made in geothermal power generation over the past decades, while geothermal direct use, particularly geothermal heat pumps (GHPs) and district heating, has been growing quickly. Development of geothermal power generation was primarily limited by the lack of high temperature hydrothermal resources near the major demand centers. A series of technological challenges associated with drilling under extremely high pressure and temperature conditions, transportation of heavy equipment, long-distance electricity transmission, and hot dry rock (HDR) exploitation, also hindered large-scale development of geothermal resources for power generation and district heating. There were no social barriers for geothermal exploitation except in hot spring tourism areas, while the high cost could limit the consumer acceptance of geothermal heating/cooling solutions. Significant investment in research and development of enhanced geothermal system (EGS) technologies for exploiting HDR resources and establishment of favorable policy instruments are recommended as key technological and policy measures to accelerate the growth of geothermal energy market, while the potential social barriers for the development EGS projects in the densely populated areas should also be recognized and mitigated in the future.