Call it a hybrid system with multiple applications for the electric grid. Southern California Edison (SCE) has signed on to be the first utility in the country to buy a project that will combine existing gas turbines with a battery storage system.
The first-of-its-kind technology is devised by Current, the new $1 billion energy services company that’s part of the General Electric empire,
“It means a more reliable electric grid,” said Colin Cushnie, vice president of energy procurement and management at SCE. “It means less emissions in the operations of the power plants to maintain a reliable electric grid.”
SCE bought two of what is called the LM6000 Hybrid EGT, which allows the turbine to operate in standby-mode without using fuel. Plus, 10 megawatts of energy storage enables immediate response to changing energy dispatch needs.
That’s important, especially in California due to the state’s ambitious requirements for renewable energy sources.
Wind and solar have taken on a greater role in the state’s energy mix but they are variable energy sources — with wind production dropping when the breeze doesn’t blow and solar dissipating when the sun goes down.
Energy storage sources are designed to help fill the gaps and the battery system in the LM6000 can help eliminate the need to constantly run the turbines at minimum loads to maintain what is called “spinning reserve” — backup energy production that’s available to a transmission system with 10 minutes’ notice.
“Just like you wouldn’t keep your car running in a parking lot,” Eric Gebhardt, chief of platforms and operations at Current said earlier this month at an energy conference in San Diego, the new system “reduces the emissions being produced and reduces maintenance costs. This is passed on to consumers and should really help (make) for a more efficient overall grid.”
The battery system for the project is scheduled to go online at the end of this year and the combined hybrid application is slated to be completely installed in the first quarter of 2017.
“We know exactly how to integrate it with the gas turbines because they’re our (GE’s) gas turbines,” Gebhardt said. “It integrates with our control systems, with our switch gears and other equipment so we can do it very quickly.”
Mike Niggli, former president and COO at San Diego Gas & Electric, said his first impressions of the technology are good.
“This is an excellent example of new age technology being connected to fossil fuel technology,” said Niggli, who is now a board member for flow-battery maker ESS, Inc.
Officials at Current and SCE say the cost is confidential but Cushnie said, “based on our economic analysis, we believe that the market value we will get from operating these energy storage devices will cover the costs of the purchases.”
If everything runs smoothly, the hybrid system will also help SCE meet some requirements specific to California.
In order to give the energy storage sector a boost, the California Public Utilities Commission three years ago issued a mandate to all three of the state’s investor-owned utilities to procure 1,325 megawatts of storage by 2020.
SCE’s share is 580 megawatts.
What’s more, in January, Gov. Jerry Brown issued an emergency proclamation because of concerns about potentially insufficient natural gas supplies due to the massive leak at the Aliso Canyon storage facility in Los Angeles County.
The CPUC called on SCE and San Diego Gas & Electric to come up with storage solutions by the end of this year to ward off the risk of power outages for the upcoming winter.
With the addition of two 10-megawatt LM6000 systems, SCE will add another 20 megawatts to its earlier total of 27 megawatts scheduled to go on line by the end of this year and the project is expected to be applied to SCE’s 580-megawatt storage mandate for 2020.
The new system is also expected to help SCE put its “peaker plants” to better use.
Operated by utilities to meet surges in energy demand in cases such as upswings in air conditioning usage, peaker plants can be built relatively inexpensively but their running costs are high because they are often used only about 5 percent of the time. California has 71 peaker plants.
The new SCE systems can use energy storage to instantaneously respond to the grid’s needs and as the battery is being depleted, if the need continues, a peaker plant can be turned on.
“The way I think about is, it probably reduces the number of peakers that are needed but it also enhances the values of the ones that you have,” Cushnie told the Union-Tribune.
Was Cushnie nervous about SCE being the first utility to buy this new technology?
“We spent a fair amount of time understanding the technology and how it would operate in our existing facilities and got comfortable pretty quickly that this is a good innovation for our electric grid and we’re excited to be the first utility to do this,” Cushnie said.