A Chinese city has launched a new residential cooling program using water from abandoned coal mines, a low-carbon initiative that could replace traditional air conditioners.

The initiative in the eastern Jiangsu province’s city of Xuzhou routes water from the now-defunct Woniushan Coal Mine to apartments in a nearby neighborhood, domestic media reported this week. The water maintains a consistent temperature of 19 degrees Celsius year-round.

Disused mines often fill with water via rainwater accumulation and groundwater seepage — water that can then be used to heat or cool nearby homes. 

Xuzhou, a former coal-producing center with a decades-long mining history, has previously used abandoned mine water for clean heating, including a system installed last winter at its former Hanqiao Coal Mine. With annual average temperatures climbing and China’s “dual carbon” initiative — where the country aims to peak its carbon emissions by 2030 and achieve carbon neutrality by 2060 — a national priority, the cooling initiative, which began June 1, has been a focus for the city. 

“After heat exchange (with the homes), the water returns to the mine, without having consumed any energy or produced any carbon emissions,” Zhang Tao, leader of the cooling project and a worker at Xukuang Heating Company, told state media outlet CCTV. Compared with traditional air conditioning, he said, this technology lowers carbon emissions and aligns more closely with China’s energy conservation and emission reduction policy.

According to domestic media, such closed-loop geothermal systems reduce energy consumption by approximately 50% compared with traditional methods. It is also estimated to reduce carbon dioxide emissions for the 100 homes in the pilot program by about 50 tons annually.

The city offered residents in the pilot program two free months of cooling, after which they’ll be charged quarterly at 4 yuan ($0.60) per square meter.

Wang, a resident in the pilot area, said that in previous summers her monthly electricity bill often exceeded 400 yuan due to air conditioner usage. In contrast, the pilot program has allowed her to cool her home for four months this summer for only 410 yuan. She said her home now maintains a constant temperature 24 hours a day, and the system is quiet, unlike air conditioners. 

Zhang, the heating company researcher, noted the great potential of the pilot program. “This year we only used a part of Woniushan Coal Mine’s capacity, and since the mine has significant potential, in the future we plan on using it to capacity, extending it to more neighborhoods.”

Editor: Marianne Gunnarsson.

(Header image: VCG)