 Tesla Inc. and PGElectric Corp. broke ground last week on a lithium-ion battery energy storage system at a PGE electric substation in the central coast of California, the companies said in a statement that called the facility a landmark. The system will be designed, constructed, and maintained by both companies, and owned and operated by PGE, they said. Construction is expected to continue into early next year, with the goal of having it energized in early 2021 and fully operational in the second quarter of 2021. Once operational, the Moss Landing substation system will be one of the largest utility-owned, lithium-ion battery energy storage systems in the world, the companies said. Stationary energy-storage systems help smooth out electric-grid peaks and valleys and make the grid more reliable. Shares of Tesla rose nearly 2 and shares of PGE gained around 1 in midday trading Wednesday. 