Sep 7, 2022 - Energy & Environment

California's power grid holds up, so far, during record heat wave

Picture of the sun behind power lines in Los Angeles, California.

The sun sets behind power lines near homes during a heat wave in Los Angeles, California on Sept. 6, 2022. (Patrick T. Fallon/AFP via Getty Images)

California's worst-ever September heat wave is putting the state's electricity grid through a big test. It held up Tuesday evening, with no rolling blackouts despite an all-time record high power demand of 52,061 megawatts.

Why it matters: Heat waves are becoming more intense, more frequent and longer lasting due to human-caused climate change, and such events are stressing our energy infrastructure in new ways.

The big picture: California is seeking to move rapidly off fossil fuels, having just passed a slew of climate-related measures, including a ban on internal combustion engine-powered vehicles beginning in 2035.

  • A large-scale grid failure during an unprecedented heat wave could call into question the state's progressive policy agenda, including its overall energy transition strategy.
  • In addition, it could create political headaches for Governor Gavin Newsom (D), a politician with national ambitions.
  • California's grid operator sought to avoid a repeat of rolling outages in August 2020, affecting about 800,000 homes and businesses, instead aiming for smaller interruptions if needed.

Zoom in: Since that event two years ago, California has moved to add generating capacity and battery storage as well as put in place electricity import agreements from nearby states.

  • Much of the additional generating capacity that has been switched on is powered by natural gas.
  • The state is seeking cleaner options to call on in coming years, including deals for battery storage that can release renewably-generated power into the grid during peak times.
  • The California ISO, which operates the state's grid, has leaned on these strategies the past few days. In addition, the state has spotlighted demand-side measures to cut electricity use during peak use periods, between about 4 and 9 p.m. local time.
  • The California ISO has implemented eight straight Flex Alerts to call for energy conservation from its customers, such as pre-cooling homes and then turning thermostats up to 78°F during peak use.

Of note: One particular text alert from the California Office of Emergency Services, delivered to cell phones Tuesday evening, had a near-immediate effect on lowering electricity demand in the state. It warned of impending rolling outages if energy use stayed too high.

Between the lines: In its "root cause analysis" of the 2020 outages, officials concluded that climate change impacts require speeding up the incorporation of better grid planning and more electricity generation.

  • Climate scientists said there is little doubt that climate change is worsening the current heat wave.
  • "We really don’t need to attribute most heatwaves individually anymore. The answer is always the same, we made them hotter," Michael Wehner, a climate researcher at the Lawrence Berkeley National Laboratory, told Axios via email.
  • Wehner tweeted that this heat wave is about 3 to 5°F hotter than it would have been in the absence of human-caused greenhouse gas emissions.
  • "For heat waves there’s absolutely no question whether climate change played  a role, all heat waves have been made more likely and more intense, how much more depends on exact location," said Friederike Otto, a leading scientist working on extreme event attribution at Imperial College London, told Axios via email.
  • She said that the rate of change in extreme heat events is a key factor in determining the societal impacts. "How fast are hot extremes getting worse with global warming and can our adaptation keep up with it?" she said.

The bottom line: The question of whether we can keep adapting our infrastructure to the shifting climate is likely to keep California power officials up at night long after this heat wave ends.

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