China Huaneng Group has launched a demonstration project in Henan Province using supercritical CO2 instead of water to extract geothermal heat. The system circulates CO2 through wells at 2.5km depths, aiming to increase heat extraction efficiency by 20% and lower energy use by 10%. By using sCO2, the project reduces reliance on local water sources and takes advantage of the fluid's unique density and flow properties. This approach treats CO2 as an industrial working fluid for district and industrial heating rather than just a waste product for storage.
