According to foreign media reports, the world's largest battery energy storage project reopened a few days ago. This battery energy storage system called Moss Landing has a scale of 400MW/1,600MWh.
Owner and operator Vistra Energy have suspended the operation and market participation of the energy storage system following a battery overheating incident in two phases of the energy storage system.
The first phase of the 300MW/1,200MWh project, which was put into operation in December 2020, ceased operation after the accident in September 2021, while the 100MW/400MWh battery energy storage system deployed separately in the second phase was put into operation one month before the accident. Still, It was also closed in February of this year.
Vistra Energy said in a July 11 statement that the battery storage system was back in operation and can now supply more than 98 per cent of the electricity it stores to the grid operated by the California Independent System Operator (CAISO). . The company earlier said it would start operations in the first half of this year.
Although Vistra Energy did not respond to industry media inquiries about the operation of the energy storage system and the progress of the investigation last month, the company revealed that it had begun to gradually restart the battery energy storage system (BESS) in May and June. The final 7MW of battery storage will also come online once the appropriate equipment (replacement of batteries and electrical components) is in place. The company said it would continue to work with regulators and local authorities as recovery efforts continue.
Vistra Energy said that it is further expanding the scale of the energy storage system, with the third phase of the project adding 350MW/1,400MWh and starting deployment in January this year. The company has previously said that the Moss Landing battery energy storage system, primarily installed in the turbine hall and other locations of a disused local coal-fired power plant, has a robust infrastructure and grid capacity of up to 1.5GW/6GWh.
California utility Pacific Gas & Electric (PG&E), the off-taker of the battery storage system operated by Vistra Energy, recently deployed its battery storage system in Moss Landing - 182.5MW/730MWh Elkhorn battery energy storage system. Vistra Energy's battery energy storage system mainly uses batteries provided by LG LG Energy Solution, while Tesla provides batteries for Pacific Gas and Electric's (PG&E) Elkhorn energy storage system.
According to findings released by Vistra Energy in January this year, the failure of the battery storage system itself was not the battery overheating, at least not in the accident that occurred in the project's first phase.
Instead, it's because the fault detection system, in response to an overheated air conditioner, triggered the water spray and mistakenly sprayed water onto the battery rack, operating at average temperature until after the water was poured—thermal runaway.
Vistra Energy's investigation report also contains some corrective actions the company said it would take.
Moss Landing Battery Energy Facility Story Timeline So Far
July 2018: Vistra Energy signed a 300MW off-take contract with Pacific Gas & Electric (PG&E) for Phase 1 of the energy storage system, while Tesla also signed with Pacific Gas & Electric (PG&E) contract for the supply of battery energy storage systems. The two battery storage systems became one of California's first large-scale battery storage systems to have a four-hour capacity contract to ensure adequate resources.
September 2018: The regulator, the California Public Utilities Commission (CPUC), approved the contracts.
· December 2020: The first phase of the Moss Landing battery energy storage system was implemented.
· June 2021: LG Energy Solutions announced the supply of battery racks for the energy storage project.
· August 2021: The second phase of the Moss Landing battery energy storage system goes online.
· September 2021: The battery overheating incident caused the first phase of the standard to interrupt operations.
· January 2022: Announced the deployment of the project's third phase with an installed capacity of 350MW.
· January 2022: Vistra Energy announces preliminary findings.
· February 2022: The project's second phase was shut down after what was described as a similar situation where activation of a water spray caused thermal runaway issues with multiple battery racks.
· April 2022: The California Public Utilities Commission (CPUC) approved the MOSS350 contract between Pacific Gas & Electric (PG&E) and Vistra Energy, which plans to deploy a 350MW/1,400MWh battery storage system in Phase 3.
· May June 2022: Moss Landing battery storage system reopens operations.
