China should speed up geological exploration and technological research to expand the use of geothermal resources, political advisers and industry experts said, despite the country being at the forefront of development and utilization of the low-carbon energy source worldwide.
The nation is rich in geothermal energy, a renewable source that can be utilized for heating, cooling, power generation, agriculture and aquaculture, said Ma Yongsheng, a member of the 14th National Committee of the Chinese People's Political Consultative Conference, the country's top political advisory body.
China has long held the top spot in direct utilization of geothermal energy globally, with geothermal heating and cooling systems covering an area of 1.33 billion square meters. This is equivalent to an installed capacity of 92.4 gigawatts that can reduce over 60 million metric tons of carbon dioxide emissions, said Ma, who is also chairman of China Petroleum &Chemical Corp.
The company, also known as Sinopec, is the world's largest refiner by volume and the country's biggest geothermal developer.
Geothermal energy, or heat emanating from the earth, is considered sustainable and clean. This heat can be harnessed from natural hot water sources, underground rock heated by the earth and molten rock called magma.
Among renewable energy sources, only geothermal energy is unaffected by natural conditions such as season and climate, and can provide uninterrupted power supply, with an annual utilization rate that is several times more than solar and wind energy.
Geothermal energy is not unusual in China, with the Xizang autonomous region, Yunnan and Sichuan provinces considered some of the best source regions.
However, the regions where most geothermal resources are located are very far from the economically developed coastal areas where there is significant demand for electricity, leading to increased costs.
In recent years, local governments have stepped up efforts to incorporate geothermal energy development into their overall energy plans.
The National Energy Administration issued a guidance in April to promote the use of renewable energy sources such as geothermal energy and solar heating.
While China has around one-sixth of the world's geothermal resources, the installed capacity of geothermal power in the country is lower than that of other renewable energy resources such as wind and solar, according to the World Geothermal Conference.
Meanwhile, despite its abundant geothermal resources, the utilization of hot dry rock resources, with temperatures of more than 180 C and buried 3 to 10 kilometers underground, is still at an exploratory stage, Ma said.
Of the three types of geothermal resources — shallow, hydrothermal, and dry hot rock — the first two are the most-developed and used geothermal resources in China.
While the country has heightened efforts to develop geothermal energy in recent years, more needs to be done to develop and utilize deep geothermal resources, he said.
Geothermal heating is by far the most economical means of heating available, and is one way of achieving China's carbon neutrality goal, said Luo Zuoxian, head of intelligence and research at the Sinopec Economics and Development Research Institute.
Fundamental research related to deep geothermal energy is relatively weak in China, and the development of high-temperature and high-pressure hard rock geothermal reservoirs faces challenges such as engineering difficulties and high costs, he said.
Ma said the country must put in place comprehensive policy support for the development and utilization of deep geothermal resources, and formulate specialized industry plans, technical standards and management regulations.
Sinopec started drilling a geothermal well of about 5,000 meters in Haikou city, South China's Hainan province, in September. This will be the country's deepest geothermal well, according to the company.
The drilling will help in understanding the formation mechanism and potential of geothermal resources in the surrounding area, lead to further exploration of geothermal resources, development of technology at the middle and deep layers, and enable the large-scale exploitation of geothermal resources from dry hot rocks, it said.
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