As I emerged from the hellmouth that is the New York City subway system in July and walked into the Time-Life building in midtown Manhattan this morning, I noticed something odd. Most of the lights in the lobby were switched off. For a moment I hoped we were having the summer equivalent of a snow day, but then I remembered that the building was enrolled in the New York utility Con Edison’s electricity load distribution program. During periods of extreme electricity consumption—like, say, a 94 F day in July—Con Ed will actually pay industrial customers like office buildings to voluntarily reduce the amount of electricity they’re using.
Voluntary load distribution is one of many ways that utilities will try to cope with what could be unprecedented demand on the nation’s electrical grid as a suffocating heat wave sweeps through the East. The heat has already killed at least 22 people, and by the weekend it’s expected to cover half the country and affect half the American populations. Records are going to fall.
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Extreme heat means extreme power use as well, as air-conditioners in homes, apartments and offices run at maximum to compensate for the high temperatures. Peak demand will likely occur in the early afternoon, when businesses are still open but people have begun to use appliances at home as well. As Jon Jipping, chief operating officer of the transmission grid operator ITC Holdings, told the AP:
These are the days everyone wants to have their ACs on, their computers going while they watch TV. These are the days we get ready for.
To meet the excess demand—which can be double the amount of power consumed during a cool day in April—utilities will activate peaker plants: small, inefficient power plants that are turned on and off as needed. Because they’re so inefficient, the power they produce is more expensive than the juice from the backbone fleet—and because the plants tend to be older, they can also lead to more air pollution as well. But when the temperature stays north of 90 F for days on end, those peaker plants are often the only thing preventing a brownout or even a blackout. And this heat wave will be particularly stressful because it will last for so long—at least through the weekend—and will cover such a large portion of the country. The grid will be reaching its limit, with little room for error.
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If all goes well—meaning no Ohio trees accidentally triggering a region-wide blackout, as happened in 2003—the grid should weather this heat wave, and all the other high-temperature days to follow this summer. But the grid is creaky—while the devices we plug into the wall become more sophisticated each day, the wires and transformers that bring us electricity is still stuck in the early 20th century. Speaking to members of his advisory board yesterday, Energy Secretary Steven Chu warned that the electrical grid might not be able to handle the new renewable electricity generation expected to be brought online over the next 10 years. (Renewable power from intermittent sources like solar or wind tends to put more stress on the electrical grid than steady sources like coal or natural gas.) More heat waves of the sort the U.S. will experience over the next few days—headed our way over the next few decades—will only stress the grid further. That sizzling sound you’re hearing isn’t just the asphalt.
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