By ANN DE ROUFFIGNAC
Nov. 22, 2000AES Corp. shut down 2,000 MW of gas-fired power plants in California last week contributing to the shortfall in generation that caused the California Independent System Operator (ISO) to scramble to meet load and to ask for voluntary curtailments in some areas.
The plants, taken out of service because of air pollution problems, will be off line until June 2001, says Aaron Thomas, spokesman for AES Pacific.
AES is moving quickly to make changes required by the South Coast Air Quality Management District, he says.
AES exceeded its nitrogen oxide emissions limits at the company’s Los Alamitos generating plant by 340 tons through Sept. 30. Credits to cover excess emissions at Redondo Beach and Huntington Beach facilities were virtually depleted, South Coast said.
To avoid further risk of violations, AES shut down Redondo Beach and Huntington Beach. The company received a notice of violation concerning the Los Alamitos facility for exceeding its emissions limit.
But no fines have been levied pending a compliance plan submitted by AES, says Bill Kelly, spokesman for South Coast Air Quality. If civil fines are proposed, the board will file a separate lawsuit asking for as much as $20 million in civil penalties against AES, he says.
California experienced a summer with extremely tight supply conditions and the ISO had to ask interruptible load customers to turn off the power day after day. Every electric power plant capable of operating was called into service to keep the lights on.
“We were called on by the ISO to run those plants,” says Thomas. “We had to keep the pedal to the metal all the time. And the Los Alamitos plants are designated as ‘reliability must run’ plants in the summer.”
However, nitrogen oxide credit market got exceedingly expensive last summer.
“The prices for the credits got up to $40/MW-hr,” Thomas says.
Each plant has an annual allotment of emissions credits. When AES accounted for the number of credits each plant used during the summer months, they had not purchased enough. AES’s own report filed to the South Coast board last week, triggered the ‘abatement’ order from the South Coast Board and the decision by AES to shut down the plants.