Blue sky thinking

China is constantly battling air pollution, especially during winter when the rise in PM2.5 - the fine particles in smog - poses a potent threat to human health. The completion of the world's largest air purifier in Xi'an, capital of Shaanxi province, has brought promising results and prompted a noticeable improvement in local air quality.

The 60-meter-high air purification tower, officially known as the Hybrid Solar Assisted Large Scale Cleaning System, is a scientific project undertaken by the Institute of Earth Environment at the Chinese Academy of Sciences, the University of Minnesota Twin Cities, and Xi'an Jiaotong University. It is the first cleaning system of its kind in the world to combine several advanced new energy technologies that can remove atmospheric pollutants effectively and prevent smog from forming.

Many local governments and businesses have expressed interest in cooperating to build more towers nationwide. The technologies used in the cleaning system are already being applied and promoted in many cities, according to a report provided by the project team. Zhang Ningning, a researcher with the project, said it has not yet been officially completed, but the research team has already submitted plans to various bodies, and more towers are expected to be built in Xi'an.

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