Vistra Energy has just been given draft approval to upgrade its Moss Landing, Monterey County, California battery energy storage (BES) site from the existing 300 MW, by adding a further 1.2 GW/4.8 GWh, making it the largest BES in the world, by a margin. Moss Landing has been the site of energy generation since 1950, when the first of multiple gas facilities was built there. It has been extended since, and then closed as the gas power station found it could not compete in wholesale energy market. The bulk of the work will take two years, but the system will not come online until somewhat later, given that the existing transmission lines will be both moved, and upgraded and new…