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Climate change and energy

Here’s how to keep California’s grid from buckling under the heat

It’s time to modernize our electricity systems—and pay people to crank down power during critical shortages.
August 18, 2020
A caution sign in Death Valley.

California’s electricity system is buckling under the strains of a blistering heat wave that may have established the highest temperature ever reliably recorded.

As residents cranked up air conditioning en masse to keep cool, the state’s primary grid operator ordered a series of rolling blackouts that have left millions without power in recent days, at least briefly. These were California’s first intentional but unplanned outages in nearly two decades, enacted in the last moments as reserves ran short to prevent a cascading series of failures across the system.

It’s a troubling development because the loss of power during a severe heat wave poses serious health risks, and because extreme summer temperatures are becoming increasingly common as climate change accelerates. California, the world’s fifth-largest economy, is also a critical test case for the reliability of an electricity grid operating with a rising share of renewable power from fluctuating wind and solar resources.

Industry observers and state electricity entities are still unraveling and arguing over a variety of issues that may have forced the grid operator to order the sudden outages—and hashing out what will be required to avoid similar events in the future.

The president of the California Independent System Operator, which oversees operation of the state’s electric power system, pointed a finger at the California Public Utilities Commission for failing to secure enough reserve electricity to provide an adequate buffer for the state. Others questioned whether the grid operator was managing the system too conservatively, enacting the rollouts when there was electricity generation to spare. Loretta Lynch, a former president of the commission, raised the possibility that electricity sellers are engaging in the sort of market manipulation that led to the California electricity crisis in the early 2000s.

What we do know is that a pair of natural-gas turbines went down on Friday, and that there was a rapid surge and then sudden slump of wind power on Saturday evening. In addition, the state couldn’t rely on resources from neighboring states as much as usual, because much of the West is also suffering through heat waves.

Severin Borenstein, an energy economist at the University of California, Berkeley, who serves on the governing board of the Independent System Operator, says the state’s growing reliance on renewables “definitely” played a role in the blackouts. He notes that the outages on Friday and Saturday both occurred as solar power was ramping down in the early evening. Changes that have reduced the share of energy coming from fossil-fuel plants, including the retirement of natural-gas facilities in California and a decrease in coal generation in neighboring states, have narrowed the safety margin for the system, he adds.

“That in no way says we shouldn’t be doing solar,” Borenstein says. “But it does mean we need to be realistic about what solar provides and what it doesn’t—and it doesn’t provide power after the sun goes down.”

The critical question: How can California—or any other region—provide reliable supplies of electricity as summers get hotter and renewables power an even great portion of our grids? Among other things, it’s going to require more energy storage, more reliable sources of carbon-free electricity, and major upgrades to aging grids.

“The grid we have is largely the one that was operating in 1980,” Michael Wara, a senior research scholar at the Stanford Woods Institute for the Environment, said in an email. “We haven’t been maintaining it, let alone upgrading it at nearly the rate we need to, over the past 40 years. And that’s despite the fact that we have decided to generate our electric power in totally different ways and mostly in very different locations.” 

But meanwhile most energy experts, including Borenstein and Ben Serrurier of the Rocky Mountain Institute, say one of the cheapest and fastest things that could help address the issue is for California’s utilities or grid operators to design and implement far more effective demand response programs.

These provide economic incentives to households and businesses to reduce energy usage during periods of high demand. Options include raising prices during peak times, lowering them during off hours, or even providing direct payments during crucial moments.

The problem is that so far, very few people even know such programs exist. The state’s utilities have done a poor job of marketing them, designing them to shift energy demand to the best time periods, communicating with customers in real time, or providing adequate incentives, observers say.

Serrurier calls it a lost opportunity, noting that if grid operators or utilities start paying a critical share of residents to simply dial up their thermostat a few degrees in the early evening during sweltering summer days, it could make a big difference in the stability of the system.

“They’re looking under the couch cushions for every megawatt hour in the West but aren’t willing to pay for someone’s voluntary action,” he says.

Whatever the precise causes of California’s outages, it’s clear these kind of updates to electricity systems and practices are necessary—and long overdue—as the dangers of climate change grow.

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Illustration by Rose Wong

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