Provinces in the north of China wasted as much as 43% of their wind power in 2016. Investment in energy storage is seen as part of the solution (Image by Greenpeace / John Novis)

Despite another banner year for renewables growth in China, the country’s grid is still struggling to bring clean electricity to consumers. The problem is so serious in China’s north and west that turbines were forced to sit idle for much of 2016.

In response, China’s policymakers are now turning to energy storage to boost the grid’s ability to accommodate wind and solar power.

But significantly increasing the share of renewables will require big changes in how China operates the grid, raising questions about how much of a role energy storage will play in ensuring that renewable energy is not wasted through curtailment.

China’s energy storage push

Energy storage technologies – which include batteries, thermal storage, pumped hydro, and more – can help integrate wind and solar on to the grid by storing energy when power demand is low, and discharging power when demand is high. Energy storage adds flexibility to the grid, allowing renewables to generate power when they would otherwise be curtailed.

Recognising this value, China’s policymakers are planning a rapid expansion of the country’s energy storage capacity. To start, policymakers are calling for new construction of pumped hydro storage facilities, which store energy by pumping water uphill into reservoirs where it can later flow down again through turbines to generate electricity. The 13th Five-Year Hydropower Plan calls for an increase in pumped hydro storage from 23 gigawatts to 40 gigawatts by 2020 – about double the existing pumped hydro capacity of the United States.