A source of geothermal energy that has the potential to supply millions of people with heating and electricity for decades has been detected in Shandong province.
The province's No 1 Institute of Geology and Mineral Resources has detected rock temperatures as high as 110 C at a depth of 1,240 meters beneath the earth's surface.
Jing Xiaodong, from the institute, said temperatures could reach 150C to 200 C at the drill hole maximum depth of 4,000 meters.
"This hot dry rock resource can be used to produce power in a very environmentally friendly way, and the cost of generating power from hot dry rock is much lower than with coal," Jing said.
The institute has located two regions of hot rock under the cities of Weihai and Yantai.
If just 2 percent of the geothermal energy contained in those two regions was utilized, it could supply Shandong with heat and electricity for 38 years, Jing said.
"We still need two more years to carry out detailed surveys on the two regions to collect data for overall exploration work," Jing said.
China started developing geothermal energy from hot dry rock in 2012. Geological and mineral resources explorers in Northwest China's Qinghai province detected rock temperatures as high as 153 C at a depth of 2,230 meters beneath the earth's surface in 2014, making the region the first known hot dry rock resource in China.
"Hot dry rock could make a great contribution to cutting China's emissions and solving our energy problems," said Wang Bingchen of the National Geothermal Energy Center at a geothermal energy forum held in Beijing in November.
Wang said the most complex technology for developing hot dry rock involves the drilling of the production well.
"The technology for drilling the production well to reach the hot rock is in its fledging step in China. Supporting technologies of developing hot dry rock should be developed as soon as possible," Wang said.