General Electric (GE) has for the first time achieved blackstart of a GE heavy-duty gas turbine using battery energy storage.
The company announced on Feb. 26 it completed black start of a GE 7F.03 gas turbine at a 150-MW simple-cycle unit at Entergy Louisiana’s Perryville Power Station using a 7.4-MW battery-based energy storage system. The unit in Ouachita, Louisiana, began operation in 2001.
GE told POWER on March 5 that the project uses lithium-manganese-cobalt-oxide (or NMC) batteries, and according to Entergy, the system is arranged in six parallel inverter/transformer pairs. It produces 7.4 MWh (DC) as embedded energy and 6.6 MWh (AC) as usable energy at the point of installation. According to a GE project leader, the battery energy storage system enables blackstart by creating a voltage reference—also known as “grid forming”—to which the turbine and its associated auxiliary power systems can synchronize. These components “then draw the required current to rotate the turbine and begin the start-up process.” GE noted that the gas turbine controls at the unit were upgraded at the same time under a separate, previously planned project that wasn’t specifically tied to the battery-blackstart project.
As Entergy told POWER on March 10, construction of the battery energy storage system (BESS) began in July 2019 and was concluded in November, and the unit was commissioned and charged in December. The blackstart test entailed “using the BESS to successfully start the 150-MW gas turbine two times on the same charge,” the company said.
GE said that the milestone project will serve as a “potential model for future projects in GE’s F-class gas turbine fleet,” which currently comprises about 900 units in service—a total combined capacity of 150 GW—in 12 countries. For Entergy, “innovative” use of the battery technology will provide “another tool to buttress the overall reliability and resiliency of our system,” as Phillip May, president and CEO of Entergy Louisiana, said in a statement.
The development is noteworthy as entities around the world explore new, more efficient, and less polluting ways for “blackstart”—a process to startup plant generator units from a completely unenergized state, without needing external power from the grid. Blackstart capability is considered especially important because it could ensure timely restoration of grid operation after a major power grid outage.
Experts note that ideal blackstart units require minimal time, fuel, and equipment, and they can be relied upon at any time to be available for blackstart. They should also have enough nameplate capacity to provide real and reactive power, and can provide station and startup power to other generators with as few transformers in the path. Finally, they must operate quickly after a blackout and continue to operate when frequency swings typically occur.
According to a May 2018 joint report by the Federal Energy Regulatory Commission (FERC) and the North American Electric Reliability Corporation (NERC) that evaluated blackstart resources across the North American bulk power system, most installed blackstart units range from small (50 MVA) to larger units ((100–200 MVA), to banks of generating units exceeding 1,000 MVA in capacity. Resources include a mix of coal and gas-fired steam units, gas combustion units, and hydroelectric units. While none of the participants at that time used wind or solar for blackstart services, interest in the use of battery storage was already surging.
In May 2017, Imperial Irrigation District (IID) in California commissioned a 33-MW, 20-MWh lithium ion based energy storage system that allowed the utility to balance power, arrest frequency decay, provide spinning reserves, mitigate large fluctuations of energy, increase voltage stability, and deliver blackstart power restoration capabilities for a 44-MW combined cycle unit at the nearby El Centro gas generation plant. At the time, the district said the installation was believed to be “a first for the energy industry.” GE, which was involved in the project, had put online one of the world’s fist battery-gas hybrid systems just months before at Southern California Edison’s (SCE’s) Center Peaker Plant in Norwalk, California. That system combined a 10-MW/4.3-MWh battery system with a 50-MW GE LM6000 aeroderivative gas turbine.
According to the latest data collected from generators via form EIA-860, the Energy Information Administration (EIA) noted that about 1,084 MWh of energy storage operated in the U.S. in 2018. Most systems provide frequency regulation, but others also offer arbitrage, load following, ramping and spinning reserve, co-located renewable firming, transmission and distribution deferral, system peak shaving, load management, voltage for reactive power support, and back up power. About 23 projects, a total 145.7 MWh, provided back up support, but it is unclear if that entails black start capability.
Amit Kulkarni, general manager for GE Gas Power’s Large Blocks product segment, said the Perryville project “demonstrates the complementary nature of gas-powered energy and battery storage, and we’re proud to integrate this technology while helping to maintain unit reliability and availability.” He added: “With the battery energy storage system integrated to our heavy-duty gas turbines, we have created a first-of-its-kind backup support system, and we are excited about developing similar projects with our customers globally.”
—Sonal Patel is a POWER senior associate editor (@sonalcpatel, @POWERmagazine)
Updated (March 7) with details from GE of how the BESS system enables blackstart. (March 11): Adds requested details from Entergy.