Southern California Edison, AES work out interconnect for repowered plant

Southern California Edison filed on March 6 at the Federal Energy Regulatory Commission a Large Generator Interconnection Agreement with AES North America Development LLC and the California Independent System Operator covering the long-planned repowering of the Huntington Beach power plant.

AES North America submitted an application to interconnect its proposed 938.61 MW (net), 973.246 MW (gross), combined-cycle thermal Huntington Beach Generating Facility, to be located in Huntington Beach, California, to the CAISO controlled grid. AES plans to retire the existing units 1, 2, 3 and 4 (approximately 870 MW (gross)) at the site by demolishing these units in their entirety and replacing them with two combined-cycle gas turbine blocks (called Block 1 and Block 2).

Each block would consist of three gas turbine generators, each unit rated at 113.825 MW, and one steam turbine generator, rated at 145.148 MW, for a net increase in generation capacity of 103.246 MW. The existing generating units 1-4 are interconnected to SCE’s 220 kV Ellis Substation via four 220 kV radial transmission lines from SCE’s Huntington Beach Substation, and the new project will interconnect at the same location. AES proposes a commercial operation date of Jan. 1, 2019, for Block 1 and June 1, 2020 for Block 2, Southern California Edison said in the March 6 filing.

The AES Southland unit of AES Corp. (NYSE: AES) is working on repowering projects for two California plants to meet various needs, including power customer commitments. AES noted in its Feb. 26 annual Form 10-K report that three coastal power plants comprising AES Southland are in areas that are critical for local reliability and play an important role in integrating the increasing amounts of renewable generation resources in California. The plants are: Alamitos (2,075 MW), Redondo Beach (1,392 MW) and Huntington Beach (474 MW).

All of AES Southland’s capacity is contracted through a long-term agreement, which expires in mid 2018 (called the “Tolling Agreement”), with Southern California Edison.

In October 2014, AES Southland was awarded 20-year contracts by Southern California Edison to provide 1,284 MW of combined cycle gas-fired generation and 100 MW of interconnected battery-based energy storage. In addition to replacing older gas-fired plants with more efficient gas-fired capacity, SCE chose advanced energy storage as a cost-effective way to ensure critical power system reliability. This new storage resource will provide unmatched operational flexibility, enabling the most efficient dispatch of other generating plants, lowering cost and emissions and supporting the on-going addition of renewable power sources, AES said.

This new capacity will be built at the existing AES sites in Huntington Beach and Alamitos Beach. For the gas-fired capacity, financing agreements are expected to be finalized in 2016, construction is expected to begin in 2017, and commercial operation is scheduled for 2020. For the energy storage capacity, commercial operation is scheduled for 2021.

AES is pursuing permits to build both the gas-fired and energy storage capacity and will complete the licensing process before financial close. The total cost for these projects is expected to be approximately $1.9 billion, which will be funded with a combination of non-recourse debt and AES equity.

About Barry Cassell 20414 Articles
Barry Cassell is Chief Analyst for GenerationHub covering coal and emission controls issues, projects and policy. He has covered the coal and power generation industry for more than 24 years, beginning in November 2011 at GenerationHub and prior to that as editor of SNL Energy’s Coal Report. He was formerly with Coal Outlook for 15 years as the publication’s editor and contributing writer, and prior to that he was editor of Coal & Synfuels Technology and associate editor of The Energy Report. He has a bachelor’s degree from Central Michigan University.