China recently switched on a massive power line designed to deliver renewable energy from its vast desert regions to the industrial heartland in the center of the country.

The Ningxia–Hunan ±800kV ultra-high voltage direct current (UHVDC) project, built by the State Grid Corporation of China, began transmitting electricity on Wednesday. It is the country's first UHV corridor built primarily to carry wind and solar power generated in desert areas, according to the company.

The 1,616-kilometer line begins in Zhongwei, Ningxia Hui autonomous region, and passes through Gansu, Shaanxi, Chongqing, and Hubei on its way to Hunan province. It has a transmission capacity of eight million kilowatts, enough to supply millions of homes, and is expected to send more than 36 billion kilowatt-hours of electricity to Hunan each year, at least half of it from renewable sources, it said.

This is Ningxia's third UHV line for exporting electricity. Officials say the project will strengthen Hunan's grid, enabling it to handle up to 16 million kilowatts from external sources. It is also seen as a key step in China's drive to move clean power from resource-rich western regions to densely populated eastern and central provinces.