This summer’s extreme heat poses a major threat to the nation’s electricity grid — yet so far, the power supply has avoided the widespread outages that many had feared. Credit new sources of wind and solar energy, along with continued supplies of natural gas and coal — and a dash of luck, writes Jason Plautz. That doesn’t mean Americans can continue to count on electrons flowing to their refrigerators and air conditioners as the planet’s warming fuels more extreme heat and violent storms, said Mark Olson of the North American Electric Reliability Corp., a national grid watchdog. “We’re seeing the grid operating at the outer limits of its capability,” Olson said. “Fortunately the operators are able to get through, but we’re seeing the creaks and groans. We should all take these signals to heart.” Hot, hot, hotter
The pressure on the power supply this summer has been unrelenting, including triple-digit temperatures across the Southwest in June and July and record heat indexes in Chicago and the upper Midwest this month. That has pushed electricity demand into “uncharted territory,” Olson said. Officials at electric utilities and the nation’s regional grids say they’re preparing for more of the same — a hot, unpredictable future. “You’d think of one hot summer as an anomaly,” said Justin Joiner, who helps run Arizona Public Service Co., the state’s largest utility. “What we’re seeing now is a trend.” Solar + gas + luck = lights on
One thing helping shore up the grid is a significant boost in solar and wind power, experts said. In Texas, for example, power demand was higher than forecast earlier this summer, and coal and natural gas plants saw significant outages. But solar, wind and battery storage stayed the course. On some days, they met as much as a third of demand. Natural gas remained a top source of power across the country too, accounting for a larger share of electricity than last summer. Luck was also a factor. A temperate spring gave grid operators time to do routine maintenance checks. A wet winter shored up hydropower in the West. And summer’s evening breezes were especially strong in parts of the country, allowing wind energy to take over when the sun set. But a changing climate could stifle future winds or fuel gusts that damage turbines and power lines. Prepping for the future
Besides gearing up for a hotter new normal, some utilities and grid operators are drawing up plans that consider factors such as growing population centers and electric vehicles. That means relying on tools such as encouraging customers to reduce power use during high demand. Some grids are also eyeing so-called virtual power plants, which let customers pool their home batteries and electric vehicles to provide backup energy.
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