By Hudson Sangree
CAISO is seeking to extend measures for another year that deal with the continuing threat to electrical reliability posed by limited operations at the Aliso Canyon natural gas storage facility, where a massive release of methane occurred in October 2015.
CAISO is seeking expedited approval from FERC to renew the temporary tariff provisions, which were first put in place in June 2016 and then subsequently refined and extended. (See CAISO Board Aliso Canyon Rules Package.)
“Our hope is to be able to keep these measures in place for another 12 months,” Anna McKenna, an assistant general counsel for the ISO, said in a conference call with stakeholders Tuesday.
The provisions include a measure allowing the ISO to enforce constraints on the maximum amount of natural gas that can be burned by gas-fired plants in the areas served by the Southern California Gas and San Diego Gas & Electric. The constraints would be based on limited supply anticipated by CAISO during specific hours.
The provisions also allow CAISO to suspend or limit the ability of scheduling coordinators to submit virtual bids if it’s determined virtual bidding could undermine reliability or grid operations.
Similar provisions have been in place for the past two years to prevent blackouts or grid disruptions caused by the natural gas supply in Southern California being over-taxed.
The current proposal, called Phase 4, would extend the temporary provisions now in place for another year beyond Nov. 30 and Dec. 16, when they are set to expire.
CAISO planned to file its proposal with FERC by Thursday and ask for a 60-day turnaround so the new restrictions are in place when the first set of rules expires at the end of November.
Before the 2015 blowout, Aliso Canyon was the state’s largest natural gas reservoir, and its damaged status poses challenges to generators and regulators alike.
Despite objections from local residents and Los Angeles County officials, SoCalGas resumed injections into the facility in July 2017 to comply with a state directive to maintain sufficient gas inventories to support reliability on the region’s gas and electric systems. (See Aliso Canyon Resumes Injections.) The California Public Utilities Commission this May authorized a temporary increase in the volume of injections to support summer grid operations but still maintains a policy of allowing withdrawals only as a last resort. (See CPUC OKs Temporary Increase in Aliso Canyon Injections.)