Two years after a spectacular stock plunge and trading suspension, Chinese solar firm Hanergy has returned to its core thin film solar business with a Rmb2.2bn ($328m) deal to build a production facility in the coal-choked city of Datong.

The deal marks a return to public fundraising by Hanergy founder Li Hejun, who for some months in 2015 ranked as China’s richest man. Mr Li has not been silent over the past two years, which he has spent battling Hong Kong regulators to allow Hanergy stock to resume trading while promoting grandiose plans to develop solar-powered automobiles.

The Datong deal signed last week is the first investment commitment by Hanergy since its suspension. Together with the Datong city government and Datong Coal Mine Group, one of China’s largest state-owned coal miners, it will build a 300-megawatt production line as part of a planned photovoltaic industry zone, according to the city.