El Centro Unit 3 Repower Project reaches commercial operation


 EL CENTRO – Imperial Irrigation District’s 140-megawatt El Centro Unit 3 repowering project has reached commercial operation and is adding power to the local electric grid.


The repowering project consisted of replacing major components of a Combustion Engineering boiler, which had been in operation since 1957, and a Westinghouse steam turbine generator at the El Centro Generating Station in El Centro, Calif. Both were replaced with a natural gas fired, combined-cycle system consisting of two combustion turbine generators, two heat recovery steam generators and a steam turbine generator.


The repowered unit will increase IID’s generation capacity by 100 megawatts, improve overall system reliability and boost fuel efficiency while reducing greenhouse gas emissions. The new unit is equipped with best available control technology (BACT) to manage air pollutant emissions, will consume one third of the water, on a per-megawatt basis, and be 45 percent more fuel efficient than its predecessor.


“Now that El Centro Unit 3 has been placed into commercial operation, it will save approximately $1 million a month in fuel costs relative to other natural gas units the district utilizes to generate power,” said Henyrk Olstowski, IID assistant energy manager in charge of generation.


The project’s in-service date was delayed due to a failure during testing that caused damage to the entire turbine core. The original turbine was returned to Sweden and replaced with a new core. A full report is expected to come forward on the cause and extent of the damage.


Olstowski emphasized that the type of failure Unit 3 suffered is rare, and that it occurred before Siemens turned control of the unit to the IID. Despite the setback, the $250 million project remains within budget. The IID has a one-year warranty on equipment and is fully insured.