The decision to permanently retire Units 2 and 3 of the San Onofre nuclear generating station (SONGS) should not affect system reliability, according to the president and CEO of the state’s grid operator, the California ISO (Cal-ISO).
“The state is in pretty good shape, overall,” Stephen Berberich, Cal-ISO’s president and CEO, told reporters during a conference call June 7. “This is largely an issue in southern Orange County and in San Diego, where we’ll particularly have issues, but the rest of the state should not have a problem.”
“It is not a surprise to us, and it is something we’ve been planning for, for some time,” he said.
SONGS went off-line in January 2012 and was out of service last summer. Last year, however, the grid operator returned to service two fossil-fired units at the Huntington Beach generating station to help make up for the shortfall from the SONGS outage. This year, those units will not be available for generation.
“We converted those [plants] to synchronous condensers [to] provide voltage support,” Berberich said. Voltage support is important because the area will have to rely on transmission to import power from outside the load pocket in SONGS’ absence, he explained.
“The voltage support allows that imported power and keeps that power flowing,” he said. The condensers are expected to enter service on June 26.
Three new generating facilities that have entered service since summer 2012 will also aid the situation. The additional power from the Walnut Creek, Sentinel and El Segundo natural gas-fired plants will be beneficial, he said, “But I don’t want to exaggerate how much help they can be because they’re outside of the specific, local area that San Onofre is in, and they’re still constrained by transmission.”
Gas-fired generation will be the most called-upon to replace SONGS’ output, and while that may serve to keep power supplies adequate, it will create additional issues.
“San Onofre … is not a greenhouse gas emitter, and it’s being replaced by energy from sources that do produce greenhouse gases,” Berberich said. “In the short- and mid-term, clearly you’re moving in the wrong direction from a greenhouse gas perspective.”
He noted that the state’s greenhouse gas trading regime will not change to accommodate that reality. While predicting that the cap and trade program will work as planned to economically force generators to reduce greenhouse gas emissions, it will “also make it more important to find some greener solutions as part of our way around not having San Onofre,” Berberich said.
The grid operator does have 1,000 MW more solar energy on its system this year than it did in 2012, he noted, adding that solar was providing 2,000 MW of power at the time of his news conference.
Longer-term solutions will also include the repowering of older generating units that are cooled by a single pass of seawater – so-called “once-through cooled” units.
Those units are supposed to retire by 2020. With the SONGS development, Berberich expects the repowering to move forward more quickly, which will provide at least three benefits. The physical footprints of modern plants are much smaller than the older coastal units, which are between 40 and 50 years old. In addition, newer plants have a lower heat rate, meaning they are more efficient, less expensive to operate, and less polluting. Finally, newer plants are more flexible than older plants, which will aid in the integration of renewable energy.
Since last summer, Cal-ISO has also completed reconfiguring the Barre-Ellis transmission line into two separate circuits, enabling more power to be imported without the risk of those imports being interrupted by a single-line contingency. Berberich also hinted that additional transmission could be a part of the longer-term solution, as transmission will be needed to bring central station renewable energy into the southern California load pocket.
Making the public aware
Cal-ISO will spend up to $10m to raise public awareness through targeted outreach in the Orange County area and in San Diego, the areas most affected by SONGS’ outage, Berberich said. The outreach will include conservation messages and public information campaigns about Cal-ISO’s Flex Alert program.
Considering everything, Berberich said he feels confident that Cal-ISO will be able to deal with the loss of SONGS in the near term.
“We have ample capacity on the system, even under the most extreme conditions,” he said. “Our one-in-ten analysis shows reserve margins to be pretty good in all areas except in that Southern California area. The rest of the state should be OK.”
Berberich called plant owner Southern California Edison’s (SCE) decision to shutter the plant, “clearly a big decision, and an important one for the electric structure in California.”
SCE is a unit of Edison International (NYSE:EIX).