Gridflex seeks changes for California pumped storage project

Gridflex Energy LLC on July 2 asked the Federal Energy Regulatory Commission for an amendment to its existing preliminary permit for the Haiwee Ridge Pumped Storage Project, located in Inyo County, Calif.

A preliminary permit allows a company three years of exclusivity to look at project feasibility, with a license application then needed if the decision is to advance the project further. This July2 amendment request, which relates to a permit first issued in March 2012, reflects the following changes:

  • elimination of the “New Reservoir” alternative;
  • reduction in scale of Alternative B from 500 MW to 250 MW;
  • reduction in extent of the project study boundary to reflect those changes; and
  • addition of affected U.S. Bureau of Land Management lands which were inadvertently omitted in the original application.

The existing dam associated with the project’s South Haiwee Alternatives A and B is the South Haiwee Dam, which is operated by the Los Angeles Department of Water and Power.

  • Equipment in Alternative A will consist of four 125-MW reversible pump-turbines, totaling 500 MW of generating capacity. Annual energy production is expected to be approximately 1,314,000 MWh.
  • Alternative B would now consist of one 250-MW reversible pump-turbine, instead of the previous four 125-MW turbines. Annual energy production is expected to be about 657,000 MWh.

The project would interconnect either with LADWP’s 230-kV Owens Gorge-Rinaldi line or with Southern California Edison’s 115-kV Control-Inyokern lines via a new three-mile interconnection line.

“The Project will be operated to provide support to new renewable resources being interconnected to the regional transmission grid currently and in the future,” the company said. “These resources—predominantly wind energy—are emissions-free and increase energy security, but are variable and intermittent in nature. The Project will use the dynamic capabilities of pumped storage to aid in the efficient integration of variable and intermittent renewable resources from both an operational and economic standpoint. The Project may also have benefits to the water quality in the South Haiwee Reservoir.”

The project contact is: Matthew Shapiro, Chief Executive Officer, Gridflex Energy LLC, (208) 246-9925, e-mail:

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.