In a significant stride toward sustainable urban heating, the Chinese mainland has officially launched its first geothermal heating project utilizing supercritical carbon dioxide (CO2) technology. Located in Zhengzhou, Henan Province, the project represents a major technological leap in how the region harnesses the earth's internal heat.
Developed by China Huaneng Group, the innovative system operates by circulating supercritical CO2 through geothermal wells that reach depths of approximately 2,500 meters. Unlike traditional geothermal systems that rely on water as the primary heat-transfer medium, the use of supercritical CO2 offers distinct physical advantages. Due to its higher density and lower flow resistance, the system improves heat extraction efficiency by roughly 20% and reduces overall heating energy consumption by about 10%.
The process is streamlined for efficiency: supercritical CO2 is injected deep underground via pipelines, where it absorbs geothermal heat before returning to the surface to provide warmth for residential areas. This method not only optimizes energy output but also prioritizes environmental preservation.
A key highlight of the project is its minimal ecological footprint. Because the system does not consume groundwater, it avoids the risks of contaminating underground geological formations and reduces disturbances to the subsurface environment—addressing common concerns associated with traditional geothermal extraction.
The impact of the project is already becoming evident. Once fully operational, the facility is expected to provide winter heating for more than 18,000 square meters of residential housing. This shift toward green energy is projected to replace approximately 288 tonnes of standard coal annually, leading to a reduction of about 750 tonnes of CO2 emissions per year.
As the world looks for scalable solutions to combat climate change, this breakthrough in Zhengzhou serves as a compelling model for the future of clean, efficient, and environmentally conscious urban heating.
Reference(s):
China launches first supercritical CO2 geothermal heating project
cgtn.com
