China's quest to store energy
Interesting article on qz, reporting on China's fast growing efforts to store excess electricity on the grid. China applies several methods for storage, but a big theme here is the high growth of battery-storage capacity. While in absolute size it's not the biggest storage method, it's year on year growth is impressive: At the start of 2018, China had an operational battery-storage capacity of 389 megawatts (MW). By August, China had added another 340 MW of additional capacity. The chart below from qz depicts the high growth rate.
Another method of energy storage the Chinese use, and with a much bigger capacity, is pumped hydro. China currently has a pumped hydro storage capacity of 30 giga-watt, which is 40 times higher than the current capacity of battery storage. The article notes;
> Pumped hydro works by storing excess electricity in the form of gravitational potential energy. When there is more electricity in the grid than necessary, the excess is used to pump water up a dam. When there’s more demand for energy than currently available otherwise, the water is allowed to fall and run turbines that generate electricity.
please find the article here