Sign In or Create an Account.

By continuing, you agree to the Terms of Service and acknowledge our Privacy Policy

Economy

Heat Waves Slam the Coasts. Will the Air Conditioners Stay On?

High temperatures are bringing electricity anxiety to sweltering cities.

A thermostat and America's East Coast.
Now It’s the Coasts Turn to Stress About Electric Grids
Heatmap Illustration/Getty Images

High temperatures from Southern California to the East Coast are putting the nation’s electric grids on alert.

PJM Interconnection, the nation’s largest electricity market which stretches from Chicago to Washington, D.C., issued emergency alerts this week, as it tries to fulfill record demand from people running their air conditioning on full blast even as power plants get stressed by high heat. While there are not yet any imminent fears of rolling blackouts, these warnings from system operators show that electricity supply is getting tight.

The East Coast is expecting quite high temperatures Thursday, with forecasted highs in the upper 90s in Washington, D.C., Newark, and Philadelphia, all major cities in PJM’s market, with high humidity throughout. In New York City, which is part of New York’s electricity market, the National Weather Service issued an excessive heat warning. The NWS has warned that the region — which includes PJM territory in New Jersey — will experience “oppressive heat and humidity” through Saturday.

Get one great climate story in your inbox every day:

* indicates required
  • On Wednesday night and Thursday morning, PJM instructed generators in its East Coast and Southern regions to “review plans” to see if any maintenance or testing that would take them off the grid could be “deferred/canceled.” It also issued an emergency alert calling for as much electricity generation capacity — i.e. power plants staying online — on the grid as possible.

    That alert, known as EEA1, “signals that PJM foresees or is experiencing conditions where all available resources are scheduled to meet firm load, firm transactions, and reserve commitments, and is concerned about sustaining its required Contingency Reserves,” according to its emergency operations manual. In other words, PJM thinks there’s enough generation to meet its expected demand, but is worried about maintaining reserves in case either demand or supply gets out of whack.

    High temperatures since June have been challenging the nation’s electric grids, with Texas grid authorities asking for voluntary conservation by consumers in June as they set a new record demand for electricity in generation. During the unrelenting heat wave in Arizona (the forecast high in Phoenix today is 113 degrees, the 28th day in a row temperatures have risen above 110), state utilities set new demand records but have not yet had any major reliability concerns. Now there are few places in America where the grid isn't being besieged by heat.

    In California, where the inland part of the state especially has been experiencing extreme heat (Bakersfield’s forecast high Thursday is 103), the state’s electric grid has either declared a low level emergency or been put on watch three times in the last week. On Wednesday, the state’s system operator said that “due to some resources going offline, continued excessive heat in interior Southern California, and transmission congestion restricting movement of power to parts of the state where it’s needed,” it had been put on watch for Wednesday evening and had initiated “demand response” programs that encourage energy conservation.

    While the California grid has remained stable, the issues it had Wednesday are known concerns when temperatures rise. Hotter conditions can lead to more-than-expected issues with power generation as plants go offline due to mechanical issues and the extreme need for electricity as parts of a power market experience extreme heat can overtax transmission infrastructure.

    California is also a global leader in solar power production, which means that the evening hours when the sun goes down but temperatures stay high can be particularly tight. The state has installed a massive amount of energy storage on the grid, however, that can be charged when it’s sunny and electricity is cheap, and discharged in the evening. At 10 p.m. Tuesday night, California's batteries were putting out about 3,500 megawatts, while its entire renewables fleet, which is largely wind at that hour, was producing 5,800 megawatts (meanwhile there was some 25,000 megawatts of natural gas on the grid).

    The California Independent System Operator also warned that it was “seeing some supply uncertainty this evening, because of heat potentially pushing up demand, and high electricity demand across the western U.S.”

    Heat waves across a broad section of the country are especially concerning for grid operation because they can inhibit imports that some grids need to stay online if an entire region of the country is experiencing high electricity demand.

    Globally, this month will likely be the hottest July on record.


    Read more about heat waves and electricity:

    The Next 2 Years Are Critical for New York City’s Electricity

    You’re out of free articles.

    Subscribe today to experience Heatmap’s expert analysis 
of climate change, clean energy, and sustainability.
    To continue reading
    Create a free account or sign in to unlock more free articles.
    or
    Please enter an email address
    By continuing, you agree to the Terms of Service and acknowledge our Privacy Policy
    Energy

    The Pentagon’s Rare Earths Deal Is Making Former Biden Officials Jealous

    The multi-faceted investment is defense-oriented, but could also support domestic clean energy.

    A rare earths mine.
    Heatmap Illustration/MP Materials, Getty Images

    MP Materials is the national champion of American rare earths, and now the federal government is taking a stake.

    The complex deal, announced Thursday, involves the federal government acting as a guaranteed purchaser of MP Materials’ output, a lender, and also an investor in the company. In addition, the Department of Defense agreed to a price floor for neodymium-praseodymium products of $110 per kilogram, about $50 above its current spot price.

    Keep reading...Show less
    Blue
    Economy

    AM Briefing: A Second Wind for Lava Ridge?

    On a new plan for an old site, tariffs on Canada, and the Grain Belt Express

    Site of Idaho’s Lava Ridge Wind Project May Be Used for SMRs
    Heatmap Illustration/Getty Images

    Current conditions: Phoenix will “cool” to 108 degrees Fahrenheit today after hitting 118 degrees on Thursday, its hottest day of the year so farAn extreme wildfire warning is in place through the weekend in ScotlandUniversity of Colorado forecasters decreased their outlook for the 2025 hurricane season to 16 named storms, eight hurricanes, and three major hurricanes after a quiet June and July.

    THE TOP FIVE

    1. Trump threatens 35% tariff on Canada

    President Trump threatened a 35% tariff on Canadian imports on Thursday, giving Prime Minister Mark Carney a deadline of August 1 before the levies would go into effect. The move follows months of on-again, off-again threats against Canada, with former Canadian Prime Minister Justin Trudeau having successfully staved off the tariffs during talks in February. Despite those earlier negotiations, Trump held firm on his 50% tariff on steel and aluminum, which will have significant implications for green manufacturing.

    Keep reading...Show less
    Yellow
    Climate Tech

    The Software That Could Save the Grid

    Or at least the team at Emerald AI is going to try.

    Technology and power.
    Heatmap Illustration/Getty Images, Emerald AI

    Everyone’s worried about the ravenous energy needs of AI data centers, which the International Energy Agency projects will help catalyze nearly 4% growth in global electricity demand this year and next, hitting the U.S. power sector particularly hard. On Monday, the Department of Energy released a report adding fuel to that fire, warning that blackouts in the U.S. could become 100 times more common by 2030 in large part due to data centers for AI.

    The report stirred controversy among clean energy advocates, who cast doubt on that topline number and thus the paper’s justification for a significant fossil fuel buildout. But no matter how the AI revolution is powered, there’s widespread agreement that it’s going to require major infrastructure development of some form or another.

    Keep reading...Show less