World's largest battery storage system for renewable energy
BYD and the State Grid Corporation of China are claiming to have built the world's largest battery energy storage station. Based in Hebei Province and fed by 140 MW of renewable-energy sources like solar and wind, the system stores up to 36MW-hours of electricity which system feeds into a smart transmission system.
All the energy is stored in rechargeable batteries supplied by BYD. The State Grid says, "the system is demonstrating a stable solution for transferring vast amounts of renewable electricity safely to the grid on an unprecedented scale".
It chose BYD's iron-phosphate battery technology based on claimed long service life (over 20 years) and also used BYD's "peak shaving & load levelling" charge and discharge methodologies. The first phase investment in the system with 100MW of wind, 40MW of solar and 36MWh of battery is over USD500 million.
The companies claim that the new battery energy storage system in conjunction with smart grids, improves renewable energy efficiency by 5-10 percent. It also provides a solution to gird instability problems that have plagued China's wind sector.