A Chinese company is turning the emissions from a coal-fired power plant into fertiliser, expanding the application of a technology that could make both carbon capture and food cheaper.

A report published on Monday by China Electric Power News cited a person involved in the project as saying that “flue gas enters from one end of the pipe, and fertiliser comes out from the other end”.

China Electric Power News is a newspaper under the National Development and Reform Commission, China’s top economic planner.

Carbon capture is the process of extracting carbon dioxide (CO2) from emissions, thereby preventing it from entering the atmosphere and causing climate change.

The captured carbon is liquefied and finally buried underground. However, this requires specific geological conditions and the whole process has high start-up and operating costs.

Jiangnan Environmental Technology (JNG) has taken a different route by using ammonia to capture the sulphur dioxide and carbon dioxide produced by burning coal, then transforming the chemicals into fertiliser. This fertiliser can then be sold, offsetting the cost of capturing the carbon.

JNG’s technology builds on years of improvements in treating industrial emissions. Starting in the early 20th century, sulphur was captured using a limestone-gypsum method, but this created large amounts of waste. Later, an ammonia-based process was widely adopted, which could turn sulphur dioxide into ammonium sulphate fertiliser.

Now, JNG has gone further by using ammonia to capture both sulphur and carbon at a coal-fired power plant. The resulting ammonium sulphate and ammonium bicarbonate are then made into fertiliser.

According to the China Electric Power News report, this process can capture about 90 per cent of the carbon produced.

In August 2025, a project using the technology began operations at a coal-fired power plant in Ningbo, in the eastern province of Zhejiang. The project can capture 10,000 tonnes of CO2 annually and make roughly 30,000 tonnes of fertiliser.

A 2025 study conducted by the Ningbo Academy of Agricultural Sciences found that the fertiliser produced by the power plant boosted rice yields by 6.2 per cent compared with rice grown using conventional fertiliser, Song Guangbin, leader of the project, told China Electric Power News.

He added that the study also found that the fertiliser significantly reduced the amount of nitrogen, phosphorus and potassium that leaked into the environment, compared with conventional fertiliser.

The novel fertiliser has also been tested on crops in Germany, France, Spain, Italy and Brazil, JNG’s website says. Switching to the fertiliser produced by its project can also cut farmers’ fertiliser costs by up to 50 per cent, the website claims.

The war in Iran has disrupted the international fertiliser market as exports from the Persian Gulf have dwindled. Since the war began in late February, the price of urea – the world’s most widely used nitrogen fertiliser – has rocketed, raising the prospect of food shortages.