NRG seeks major revamp of Carlsbad gas project in California

The California Energy Commission said in a May 29 notice that it will take comment on an April 29 petition from NRG Energy’s (NYSE: NRG) Carlsbad Energy Center LLC for changes to a final decision for the Carlsbad Energy Center Project (CECP).

The 540-MW, combined-cycle project was certified by the commission in May 2012. The proposed facility will be located in the City of Carlsbad in San Diego County.

The modifications proposed in the April 29 petition would allow Carlsbad Energy Center to demolish three additional, aboveground fuel oil storage tanks and associated piping and equipment. According to the petition, the proposed revisions would benefit CECP construction by providing additional equipment laydown, construction parking and staging areas, and direct access to the construction site from one of the main construction access roads.

Besides the April 29 petition about removing these existing facilities, the company on May 13 filed with the commission a major update on the project itself. The changes are designed to improve the project’s ability to meet regional electrical resource needs, as determined by San Diego Gas and Electric (SDG&E). These improvements include contributing to electricity reserves that generally will ensure a reliable energy supply, and providing local and electrical transmission grid support in San Diego County and the southern California region.

The proposed changes also address and mitigate many of the expressed reasons for community opposition to the project voiced when the project was licensed. Consequently, the City of Carlsbad supports the amended project, as indicated in a letter of support dated April 23.

Existing plant at the site will be demolished once new plant is ready

The company proposes the demolition of the adjacent Cabrillo Power I LLC Encina Power Station (EPS) facilities after this project is complete. This May 13 petition to amend (PTA) includes the above-grade decommissioning and removal of EPS Units 1 through 5 and other existing buildings and support facilities at EPS. The shutdown of existing EPS Units 1-5 will provide emission offsets and will comply with California’s Policy on the Use of Coastal and Estuarine Waters for Power Plant Cooling (Once-Through Cooling Policy).

The amended CECP is proposed to come online by the fourth quarter of 2017, and demolition of the above-grade EPS generating units, buildings, and related equipment would commence as soon as practicable after that.

The amended CECP will be a simple-cycle facility configured using six 100 MW (nominal), natural-gas-fired combustion turbines with a capacity of 632 MW (net) output. Similar to the already licensed version of the CECP, the amended CECP’s units will interconnect via 138-kV and 230-kV lines that connect to the respective, neighboring SDG&E switchyards.

The six combustion turbines will be General Electric LMS100 units, which boast the highest simple-cycle thermal efficiency, in excess of 44%, of any comparable technology. The combustion turbine generators (CTGs) will be supported by common, balance of plant (BOP) equipment including a bulk water storage and treatment plant, fuel gas compressor enclosure, compressed air system, fire protection enclosure, and an aqueous ammonia storage area.

Each GE LMS100 turbine is capable of reaching 100% load in 10 minutes or less with ramp rates up to 50 MW per minute, providing rapid response to changes in grid demand, the company noted.

This is a major revamp, since the 2012 original approval for this project covered a 558-MW (gross)/540-MW (net) combined-cycle facility configured using two units with one natural-gas-fired combustion turbine and one steam turbine per unit.

Natural gas will be delivered to the amended CECP from the existing SDG&E transmission pipeline (Line TL 2009, called the “Rainbow line”) via an approximate 1,100-foot-long interconnection pipeline west of the site that runs parallel to the existing railroad tracks.

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.