China’s largest utility has started construction on a 28 billion yuan ($3.9 billion) project to transmit electricity across three provinces and store it in mountain reservoirs as the country integrates growing amounts of intermittent renewable energy.

The project includes a 1,069-kilometer (664-mile) ultra-high-voltage power line from northern Shaanxi province to the outskirts of Hefei, a city of almost 10 million in eastern China, state-run Beijing Youth Daily reported. Near its terminus it will be connected to a 1.2 gigawatt pumped hydro station that uses reservoirs at different heights on mountains to store energy through gravity and water.

The power line will be fed by solar and wind power, with coal generators acting as backup. China installed record amounts of solar panels and wind turbines last year, and as their share grows local grids are struggling to handle the increasing amount of intermittent generation.

by bnnbloomberg