Edison International
09/16/2024 | News release | Distributed by Public on 09/16/2024 17:20
What is Energy Storage
Energy storage is a flexible energy resource. There are different types, with the most common today being battery storage.
Storage technologies like lithium-ion batteries, which are used in your laptop or phone, capture and store solar energy during times of low demand - when it is plentiful and inexpensive - and saves it for times of high demand, when energy is in shorter supply and more expensive.
Battery storage can also help smooth out the fluctuations in renewable resources - because the wind does not always blow and the sun does not always shine - by storing excess energy they generate and supplying it to the grid later.
Before storage capabilities, excess energy generated by solar panels was lost, unable to be used later.
Since 2020, SCE has increased its energy storage capacity by 3 gigawatts which can power about 2.25 million homes for four hours.
"Lithium-ion technology stands as the cornerstone of modern energy storage," said Juan Castaneda, SCE's principal manager of Grid Technology Innovation. "If we are really serious about a grid that delivers 100% clean energy, you cannot meet that goal unless there is storage solution on a massive scale to capture excess renewables. Storage is what makes an intermittent resource like renewables dependable."
Battery storage is becoming more common in residential solar system installations, as well as large-scale installations at electrical substations that can provide power for millions of customers.
Since 2020, SCE has added approximately 3 gigawatts of energy storage, which can power about 2.25 million homes for four hours, and most of these resources are lithium-ion batteries. And the numbers will continue to grow as part of Edison International's Countdown to 2045 plan for helping achieve California's emission-reduction goals.
The adoption of energy storage for homeowners is also rising. In the last three months alone, about 70% of all SCE residential solar applications included storage.
Storing excess energy using lithium-ion batteries can help supply the grid with power when it is needed most, when the sun is not shining and wind is not blowing.
The ability to store the excess power from solar and use it whenever needed helps customers save on electric bills by using the energy during more expensive peak hours while also being more resilient in emergency power outages.
While battery energy storage is relatively new, especially at the scale it is being used today, other forms of energy storage have been around for decades.
A smaller percentage of SCE's storage portfolio is pump storage, with most of that being provided by the John S. Eastwood Pump Storage Plant - in the High Sierras - next to the company's Big Creek hydroelectric generating system.
"When we have an excess of energy in the system, we use energy from the grid to pump up water from a lower lake to a higher lake," said Castaneda. "Then you release the water when demand is high, passing through turbines to generate electricity."
Learn more about how energy storage technology benefits the grid at edison.com/innovation.