ONTARIO, Calif.—East of LA, a natural gas peaker plant surrounded by fields of cows got a new, futuristic neighbor. Under a maze of transmission lines, a 20MW battery storage facility made of nearly 400 closet-sized batteries sitting on concrete pads now supplies 80MWh to utilities.
The project is an anomaly not just because it’s one of the largest energy storage facilities on the grid in California today, but also because it was built in record time—the project was just announced in September when regulators ordered utility Southern California Edison to invest in utility-scale battery storage, a year after a natural gas well in Aliso Canyon, California, sprang a leak and released 1.6 million pounds of methane into the atmosphere. The leak prompted a shutdown of the natural gas storage facility, one of the largest west of the Mississippi. Regulators were concerned that such a shutdown would cause energy and gas shortages, although that worry has not come to fruition entirely , and SoCal Gas has begun tentatively withdrawing gas again in recent weeks.
The ability to store electricity is something that appeals to state regulators because it also moves toward helping intermittent renewable energy—like wind, which only is produced when wind blows, or solar, which only is produced when the sun shines—become baseload energy. If you can store it after it’s produced, then you can call upon that energy to feed the grid at any moment, even when wind and sun are absent.
The Tesla battery facility is situated on 1.5 acres, and it’s modular in design—two 10 MW collections of 198 industrial-grade Tesla Powerpacks and 24 inverters are connected to two separate circuits at the Mira Loma substation. Unlike its neighboring Mira Loma natural gas peaker plant, which operates to make up for over- or undersupply of energy on the grid, the new battery facility operates only when there’s immediate demand. Southern California Edison’s market operations group submits bids for the energy at the battery plant and the California Independent Systems Operator (CAISO), a nonprofit that oversees the state’s electric system, will award the bid if a customer needs that battery power.
On Monday, a variety of utility officials, local politicians, and Tesla employees gathered for a ribbon-cutting ceremony for this storage facility, which is already operational. J.B. Straubel, Tesla’s chief technical officer, noted that these Powerpacks were all manufactured at Tesla’s Gigafactory outside of Reno, Nevada. The industrial Powerpacks are essentially larger versions of Tesla’s home-storage Powerwall unit, and Straubel noted that although the chemistry of the lithium-ion batteries is slightly different from the chemistry of Tesla vehicle batteries, the company used much of what it learned from building Tesla car batteries to inform the designs of the stationary storage units. The batteries are second-generation stationary storage units from Tesla, which are doubled in energy density from the unit that Tesla announced in May 2015.
Southern California Edison officials said that the site in Ontario was chosen from 70 potential sites, which they narrowed down based on land availability, means of interconnection with transmission lines, and ability to construct the site quickly. Kevin Payne, the CEO of Southern California Edison, told journalists on a tour of the facility that the speed of construction is unlikely to be repeated, given that other sites may not have the ideal characteristics that this site had. “These projects are not likely to always be a three-month turnaround. There was a special urgency with one... but if you look around you, this was just dirt a few months ago…so this one I think shows what can be done with all the right urgency and stars aligning,” Payne said.
Payne also noted that storage facilities were getting more and more sophisticated. He cited an earlier demonstration project called the Tehachapi Energy Storage Project, which went online in 2014 and at the time was the largest energy storage facility in North America. But Tehachapi "only provided 40 percent of the storage you see here," Payne told the audience on Monday.
California has committed to cutting its greenhouse gas emissions to 40 percent of 1990 levels by 2030, meaning the state is looking to add more renewable energy to the grid. But Michael Picker, commissioner of the California Public Utilities Commission (CPUC) noted on Monday that part of reaching that goal is going to mean electrifying the transportation sector, which will create extra demand that utilities will need to meet. Currently only 20 percent of California’s greenhouse gas emissions come from utilities, but 40 percent comes from transportation. Tesla, of course, is working on that end of the emissions-creating spectrum, too, with its electric vehicles.
Two other energy storage facilities are being built in California currently. San Diego Gas & Electric is building a system with AES Energy Storage, and AltaGas is building a system with Greensmith Energy Partners, according to the Los Angeles Times. In total, the three projects will add 77.5 MW of storage capacity to the grid.