California now has the largest battery storage facility in the world at Monterey Bay. Moss Landing Energy Storage Facility added 100 megawatts to the 300 megawatts of capacity that went online in December 2020, for a total of 400 megawatts at the facility. The storage facility is about the size of three football fields with large concrete boxes housing endless racks of batteries. The lithium-ion batteries can run for up to four hours on a charge, for a total power level of 1,600 megawatt-hours. The additional 100 megawatts adds to the 1,438 megawatts of utility-scale battery storage capacity the state had as of June 2021.
However, on Labor Day weekend shortly after that addition was made, battery modules at the facility overheated, scorching battery racks and melting wires, and placing the storage facility offline at a time when California could be threatened by rolling blackouts and was taking the precaution of installing five “temporary” natural gas plants. That is not the first time a fire threatened a battery storage facility. In April 2019, a fire occurred at a facility in Arizona that caused Arizona Public Service to pause new battery storage projects. A lithium-ion battery container near Phoenix caught fire, and after first responders opened the door to the enclosure, it exploded, sending several of them to the hospital. The explosion revealed that lithium-ion batteries can be dangerous, even in the hands of experienced and trained professionals.
Besides the safety issue, there is a question of whether they can really do the job. In Australia, Tesla Big Battery, one of the world’s biggest lithium-ion batteries, is facing legal action amid allegations that it failed to deliver on providing services essential to maintaining the stability of the power grid. The Australian Energy Regulator filed Federal Court proceedings against the Tesla Big Battery, known as the Hornsdale Power Reserve. Tesla built the 150-megawatt battery in South Australia in 2017, paired with the adjacent Hornsdale wind farm. It can provide 193 megawatt-hours of storage. The lawsuit alleges that Hornsdale Power Reserve failed to provide “frequency control ancillary services” – services used to maintain the safe operations of the grid following power disruptions – despite making offers and receiving payment from the market operator to be on stand-by to provide them.
Battery Storage in the United States
As of June 2021, the Energy Information Administration reported that the United States had 2,380 megawatts of battery storage capacity with California having more than the other 9 states combined. Texas, which has 343 megawatts, the second most in the country, added storage capacity after its blackouts in February 2021 when a cold spell hit the state and generation from its wind units dropped precipitously.
While the California Moss Landing facility is currently the largest battery storage facility at 400 megawatts, there are at least a half-dozen other U.S. battery storage projects in development that are in the same size range. One of them is scheduled to go online this year in Florida, the 409-megawatt Manatee Energy Storage Center, being developed by Florida Power & Light, and which can run for about two hours on a charge. Recently, the Energy Information Administration issued a report indicating that 10,000 megawatts of storage capacity is expected to be added to the grid between 2021 and 2023—10 times the capacity that was online in 2019.
Build Back Better Act Supports Battery Storage
On September 15, the House Ways and Means Committee approved a portion of bills drafted for inclusion in the $3.5 trillion budget reconciliation legislation — the Build Back Better Act. The Bill expands the production tax credit (PTC) and the investment tax credit (ITC) to cover other “green” energy technologies, including energy storage technology. The Bill would expand the ITC to cover standalone energy storage projects, including equipment that uses batteries, compressed air, pumped hydropower, and certain other storage property used to store energy for conversion to electricity with a capacity of at least 5 kilowatt hours. Under current law, energy storage property can qualify for the ITC only if it is part of an otherwise ITC-eligible project (typically solar or wind) and certain other requirements are met.
Other Issues with Battery Storage
Besides having to mitigate the risk of fires, other issues concerning large battery adoption include the potential for shortages of and foreign dependency upon materials such as lithium, the environmental harm of mining for those materials, the cost of battery recycling and the environmental effects of battery disposal. Despite China having the 4th largest reserves of lithium, Chinese chemical companies account for 80 percent of the world’s total output of raw materials for making lithium batteries. China is rapidly buying up stakes in lithium mining operations in Australia and South America, where reserves are more plentiful. China also dominates lithium battery production with 101 of the 136 lithium battery plants.
The lithium extraction process uses a lot of water—approximately 500,000 gallons per metric ton of lithium. To extract lithium, miners drill a hole in salt flats and pump salty, mineral-rich brine to the surface. After several months the water evaporates, leaving a mixture of manganese, potassium, borax and lithium salts which is then filtered and placed into another evaporation pool. After between 12 and 18 months of this process, the mixture is filtered sufficiently that lithium carbonate can be extracted. In Chile’s Salar de Atacama, mining activities consumed 65 percent of the region’s water, which is having a large impact on local farmers where some communities have to get water elsewhere. Lithium extraction harms the soil and causes air contamination. In Argentina’s Salar de Hombre Muerto, residents believe that lithium operations contaminated streams used by humans and livestock and for crop irrigation.
Lithium ion batteries contain hazardous materials and are hard to recycle. In Australia, only two percent of the country’s 3,300 metric tons of lithium-ion waste is recycled. Discarded products often end up in landfills, where metals from the electrodes and ionic fluids from the electrolyte can leak into the environment.
Because lithium cathodes degrade over time, they cannot be placed into new batteries. A major source of pollution in lithium-ion batteries is the electrolyte. The lithium hexafluorophosphate in the electrolyte is hydrolyzed in the air to produce phosphorus pentafluoride, hydrogen fluoride, and other harmful substances, which is a major threat to soil and water resources. Phosphorus pentafluoride is a strong irritant to human skin, eyes, and mucous membranes, and is also a very reactive compound that hydrolyzes in humid air to produce toxic and corrosive white fumes of hydrogen fluoride. Hydrogen fluoride is so strong it is typically used for etching glass.
To be 100-percent renewable would take vast numbers of batteries and require numerous days of storage. A recent analysis of Germany’s goal for 100-percent renewable energy found that Germany would require investments in renewable energy generation of 130 percent of their annual load requirements and electricity storage equivalent to 61 days per year of German consumption of energy to ensure adequate supplies of reliable electricity. Much of the generation of excess load would be required to generate emission-free hydrogen and store it to meet needs when intermittent wind and solar fail to produce sufficient electricity. Given the enormous costs of battery storage, the challenges of hydrogen and the volume of renewable energy necessary to guarantee Germany a reliable source of electricity, this requirement is daunting. It would be even more daunting for the United States given that Germany is 28 times smaller than the U. S., or about the size of Montana.
Battery storage is taking off to meet President Biden’s goal of an 80-percent carbon free grid by 2030. The Build Back Better Act that the House Democrats have written includes incentives for storage capacity. But, issues remain regarding safety, deliverability, mining and availability of lithium, and recycling and disposal of used batteries. Is the United States rushing into a technology that is needed to back-up intermittent renewables without carefully understanding the ramifications?