The Current Status and Development Recommendations for Dry Hot Rock Fracturing Technologies at Home and Abroad

Dry hot rock is a special geothermal resource featuring large reserves, wide distribution, clean energy generation, and recyclability. The United States, France and other countries have successfully developed and utilized dry hot rock to generate electricity and heat. Abundant dry hot rock resources have been developed in southern Tibet, western Yunnan, and the coastal areas of the southeast China, but they have not yet been exploited effectively. The efficient development of dry hot rock is of great significance in adjusting energy structure, reducing environment pollution, and coping with climate change challenges. Proper hydraulic fracturing can generate a complex fracture system in thermal reservoirs that will enhance heat exchange volume, which is the key element in the transformation from dry hot rock resources into energy. Based on the research status of dry hot rock fracturing technologies worldwide, this paper analyzed the characteristics of foreign main dry hot rock fracturing technology, and pointed out the situation and difficulties of fracturing faced in the development of dry hot rock in China. It is recommended in this paper that research focus on high temperature dry hot rock mechanics and in-situ stress characteristics, rupture and extension mechanisms of frac under thermal stress, ultra-high temperature staged/zonal fracturing tools, volume fracturing design method for high temperature hard formation and software development, and long-term real-time monitoring of fractures so as to develop the matched fracturing technology as soon as possible. At that point it can then promote the development and utilization of dry hot rock resources.