Will California’s grid hold up this summer? Energy officials are guardedly optimistic
It's a summer rerun nobody in California wants to see: A repeat of the last August's two straight days of rolling blackouts.
And while hot weather may exacerbate a strained electric grid in the coming months, officials with the California Public Utilities Commission, the California Energy Commission and the California Independent System Operator are guardedly optimistic there will be no power interruptions this time around.
For one thing, the system operator that manages the electric grid for about 80 percent of the state and the utilities commission estimate there will be 3,000 to 4,000 megawatts of additional power at the ready this summer, compared to 2020. That's for a system that approaches 50,000 megawatts of capacity at its peak.
In addition, the three agencies said at a virtual workshop Tuesday they have been working with each other — as well as with water and power authorities in and out of state government — to squeeze out every megawatt that will be needed in the coming months.
"In this era of climate change and severe weather and uncertainty, no one can predict 100 percent," said Marybel Batjer, president of the utilities commission, known as the CPUC for short.
"But I feel that what we have undertaken since last August and September, the different reforms we have made, the modifications to existing programs that we have made, I think we have picked up the corner of the tent and examined everything very carefully ... and made some changes that I think have taken us a long way to a measure of certainty."
On Aug. 14 and 15, a severe heat wave led to a surge in electricity demand as Californians cranked up their air conditioners. The system operator, known as the CAISO, declared a Stage 3 Emergency both days because it could not maintain the required 6 percent minimum in contingency reserves.
The outages lasted as long as 2 1/2 hours in some parts of the state on Aug. 14 and 90 minutes on Aug. 15. It marked the first time since the California energy crisis of 2000 and 2001 that the Golden State had experienced statewide blackouts.
If not for emergency measures that brought in extra energy sources and everyday consumers reducing their electricity demand, there would have been more blackouts Aug. 17, 18 and 19. Another heatwave over the Labor Day weekend nearly led to other rounds of outages.
Normally, California grid operators can obtain needed power from neighboring states but the heat wave in August extended across the West, and energy that otherwise might be imported to California stayed in places like Arizona and the Pacific Northwest. That's still a concern. "Overall, capacity conditions are better this year than 2020," said CAISO senior manager Robert Emmert, "but the grid remains vulnerable to high loads and available imports during widespread heat events, especially with significantly low hydro conditions this year."
A lack of rain has depleted many of the hydroelectric dams across the state.
On other hand, Emmert said the system this summer will have 10 times more battery energy storage available than last year.
Among other directives, the CPUC ordered the state's three big utilities to procure at least an additional 2.5 percent of resources, thus increasing the planning reserve margin from 15 percent to 17.5 percent.
There have also been efforts to reduce electricity consumption through "demand-response" initiatives, such as a pilot program that would compensate customers for voluntarily reducing energy use in the event of a grid emergency.
"It's not really a single agency and it's not a single solution," said David Hochschild, chair of the Energy Commission.
"It's silver buckshot, not a silver bullet."
Shortly after the outages, the CAISO discovered a computer glitch inside its day-ahead market trading system led to several thousand megawatts of power in California actually getting exported to other states — at the same time the Golden State needed them.
The glitch was quickly rectified but some critics say CAISO, CPUC and CEC officials have gone overboard in the wake of the blackouts and overprocured sources of energy, with the cost getting passed on to ratepayers.
"We have to have some more shock absorber in the system," said CAISO president Elliot Mainzer. "We have to have a little more margin for error and we do need to look at that reserve margin. Remember, it's not just the CAISO's reserve margin. We all share this in the state. You can't be living that close to the edge."
Last summer's outages highlighted a critical change in grid management.
In the past, operators worked on the principle that if they had enough capacity to meet "peak demand," there would be enough to cover all the other hours of the day.
But with an increase in solar penetration in recent years, the bigger challenge comes a bit later, during "net peak demand." That's when demand is not at its highest but is still strong and solar generation sharply dissipates as the sun sets. Grid operators then have to find other sources of power to meet the drop in solar to keep the system balanced.