San Diego Gas & Electric has began to install two lithium ion battery storage facilities.
Construction began near Escondido, California in August 2016. By the end of January 2017, they should be up and running.
These are not small projects. One will have a capacity of 30 MWh and the other 120 MWh.
The latter will be the largest lithium ion battery system on any utility grid in the world.
Southern California Edison and Tesla started on an 80 MWh project in September. They plan to have theirs online even sooner. So it will be the largest in the world for a little while.
Why the rush?
California, natural gas, and the rupture
California has no petroleum-fired or coal-fired generating plants. It will soon shut down its last nuclear generator. In September it generated just over 2 million MWh from hydroelectric plants. It produced just 4 million MWh of electricity from other renewable sources. California generates more electricity from natural gas, more than 9 million MWh, than from all other sources combined.
California electric utilities purchase gas from other states and store it. Wells at the storage sites pump gas as needed by more than a dozen different power plants.
Southern California Gas Company’s Aliso Canyon Storage Facility is one of the nation’s largest.
It was built in a depleted oil field very close to the Porter Ranch neighborhood of Los Angeles.
It comprises 115 wells to extract 86 billion cubic feet of natural gas in sandstone formations a mile and a half under Oat Mountain.
SoCalGas workers discovered on October 23 2015 that well SS-25 had ruptured. Although it didn’t receive nearly the news coverage as the Deepwater Horizon oil leak, it was a disaster on the same order of magnitude.
It took the company two days to report the leak to state regulators, three days to report it to county fire officials, and five days to issue a press release to notify nearby residents.
Like Deepwater Horizon, the first attempts to stop the leak failed. Crews could’t bring it under control until February 11, 2016. They did’t finish sealing it until the 17th. At its peak, it leaked 58 metric tons of methane into the atmosphere every hour. That’s nearly 1,400 metric tons every day. It forced 8,000 families to evacuate their homes.
The facility remains closed. Among other consequences, it has created a shortage of natural gas. Power plants must scramble to find ways to meet demand for electricity.
Accelerated lithium ion battery system
To avoid blackouts, the California Public Utilities Commission took several measures to mitigate the problem, including streamline procedures for procuring storage. It ordered utilities to identify projects they could have up and running in a few months.
Deployment of new technology usually takes years to find a suitable site, design and build a facility, and starting to operate it.
The initial order only applied to Southern California Edison. Its service area includes Porter Ranch and other areas directly affected by the rupture.
The commission had previously ordered San Diego Gas & Electric to install 165 MW of storage. So when the order to fast-track additional storage expanded to other utilities, SDG&E was ready. Its two new projects total 37.5 MW, which is less than a quarter of what it had already installed.
Even with previous experience, the new batteries near Escondido would have ordinarily taken a year to design and build. The mandate to move from drawing board to an operating system in a few months presented a big challenge. The utility chose AES as its partner because it is the largest battery maker in the world. And it had recently deployed six projects.
The new systems will provide 37.5 MW for four hours a day. Added to the existing 165 MW, they will enable the utility to use stored energy during peak periods instead of gas-fired peaker plants.
Lithium ion batteries are probably not a long-term solution. The batteries will charge and discharge completely almost every day.
The more a lithium ion storage system is cycled, the faster it degrades. That kind of battery has also proved to be a fire hazard in consumer electronics.
The gas well that failed was 62 years old. Numerous worn parts must have been replaced multiple times in that span. Then the system failed.
The industry must find an alternative to lithium ion storage systems before the new installations in Escondido and elsewhere become elderly and fragile. Researchers have been exploring different kinds of utility-scale batteries for years now.
In the meantime, the disaster at Aliso Canyon has resulted in a demonstration that storage of electricity can replace natural gas at least at peak periods.
Given sufficient generating capacity from solar, wind, and other resources, fossil fuels will likewise become unnecessary for baseline power plants.
Aliso Canyon 1 year later: How a massive gas leak left its mark on Porter Ranch / Dana Bartholomew, Los Angeles Daily News. October 22, 2016.
California state profile and energy estimates / U.S. Energy Information Administration
Inside construction of the world’s largest lithium ion battery storage facility / Gavin Bade, Utility Dive. December 6, 2016
Lithium ion battery system. Some rights reserved by Portland General Electric
Aliso Canyon gas leak site. Photo by Earthworks. Public domain from Wikimedia Commons
Vanadium flow battery. Photo by UniEnergy Technologies. Public domain from Wikimedia Commons