TL;DR: U.S. grid operators say households should be ready for tighter power supplies and possible rolling blackouts in extreme weather as AI data centers drive record demand growth.

Why utilities are warning households now

According to Energy News Beat, U.S. utilities and grid operators are urging households to prepare for tighter electricity supplies, possible rolling blackouts during extreme weather, and new risks from large loads like data centers. The report published September 7, 2026, ties the warning to rising demand, plant retirements, and weather-dependent additions.

According to Reuters, blackout risk was expected to escalate on Wednesday, September 2, 2026, as intense heat tested capacity serving millions of homes and businesses from the Midwest through the Mid-Atlantic. Reuters reported that the U.S. Department of Energy warned of heightened blackout risks in the PJM Interconnection, the largest U.S. grid operator.

Reuters also reported that the Department of Energy authorized PJM to use backup generation before a level 3 emergency alert. The same report said MISO said Wednesday peak demand could reach about 121 gigawatts, near record territory, and that electric customers in rural Missouri were asked to reduce consumption.

The message for households is direct: plan for interruptions during heat waves and winter peaks even when operators describe generation as sufficient for expected conditions. According to Energy News Beat, ERCOT posts seasonal updates emphasizing sufficient generation for expected conditions while reminding customers to contact local providers during outages.

What the long-term reliability assessment found

According to Energy News Beat, the January 2026 NERC 2025 Long-Term Reliability Assessment finds the overall resource adequacy outlook worsening, with 13 of 23 assessment areas facing challenges over the next decade as demand from AI data centers and other large loads outpaces planned generation and transmission.

Summer peak demand is projected to rise by more than 224 GW over 10 years — 69% higher than the prior forecast — while winter demand grows even faster at 245 GW, according to Energy News Beat's summary of the assessment. The report describes the assessment as based on mid-2025 industry forecasts.

Most near-term additions are batteries and solar PV, which are weather-dependent and inverter-based, while fossil-fired retirements continue, according to Energy News Beat. That mix increases winter shortfall risks.

NERC classifies several regions as High Risk, meaning shortfalls possible even under normal peaks, or Elevated Risk, meaning shortfalls more likely in extreme conditions, starting as early as 2026–2029 in areas including parts of MISO, SPP, PJM, ERCOT, the Northwest, and Basin, according to Energy News Beat. The assessment emphasizes expediting resources, managing retirements flexibly, and coordinating on large-load growth.

According to Utility Dive, MISO told the Federal Energy Regulatory Commission that on average electric demand was relatively flat between 2009 and 2024, growing by about 0.5% a year. MISO now expects 1% to 2% annual growth through 2044, with higher growth rates in the near term, according to Utility Dive.

The July 22 data-center event that rattled the East

According to Energy News Beat, a concrete example of emerging risks occurred on July 22, 2026, in Northern Virginia's "Data Center Alley." A transmission line fault prompted clusters of data centers to automatically switch to backup power, instantly removing roughly 3–3.8 GW of demand — about 3% of PJM's load at the time.

This created a sudden surplus that caused voltage and frequency swings rippling across the Eastern Interconnection, according to Energy News Beat. Sensors detected disturbances from Northern Virginia to Chicago, with flickering lights reported in homes.

The grid stabilized in about 10–11 minutes with no cascading blackout or customer outages, but PJM initiated a synchronized reserve event, according to Energy News Beat. Similar but smaller events happened in 2024 and 2025.

PJM serves 13 states and 67 million people, according to Energy News Beat. PJM and Dominion Energy confirmed the data centers' own protection systems triggered the transfer, and the utility did not shed load, according to Energy News Beat.

Experts called it a warning: as individual campuses approach gigawatt scale, simultaneous "ride-off" behavior can stress the grid far beyond a local fault, according to Energy News Beat. NERC and FERC have flagged large computational loads as a reliability concern requiring better modeling, ride-through standards, and coordination.

NERC's Level 3 alert on gigawatt-scale swings

According to Energy-Storage.News, the North American Electric Reliability Corporation issued its Level 3 Essential Action Alert with a 3 August deadline for utility responses. The September 1, 2026, report describes it as the most urgent grid reliability warning in response to artificial intelligence data centers causing massive, near-instantaneous power fluctuations.

The alert outlined seven mandatory actions for registered entities to implement immediately, citing "customer-initiated large load reductions and significant oscillations that occur in seconds, leaving little or no room for real-time responses, threatening bulk power system reliability," according to Energy-Storage.News.

According to Energy-Storage.News, Thomas Sisto, co-founder and CEO of flow battery company XL Batteries, said events have been seen where 1,000 MW or more dropped off the grid in a matter of seconds. The same report says individual AI campuses are beginning to consume electricity on the scale of small cities, while computational workloads create demand that can swing rapidly.

According to Energy-Storage.News, Dr. Hooman Ghaffarzadeh, director of power systems engineering at Wärtsilä Energy Storage, said data centre loads are highly dynamic and can go from zero to 100% in just a few milliseconds, with changes recurring every 10 milliseconds. The report says hundreds of thousands of graphics processing units ramping nearly simultaneously can create a very large change in demand very quickly.

Traditional grid monitoring happens at the substation or transmission level, often with seconds or minutes of lag — far too slow to catch millisecond-scale disturbances, according to Energy-Storage.News. Matthew Williams, founder and CEO of IONATE, said utilities often lack a real-time picture of voltage fluctuations and other power quality disturbances, according to Energy-Storage.News.

New rules for large loads in MISO, PJM, and Texas

According to Utility Dive, the Midcontinent Independent System Operator on Aug. 28, 2026, asked the Federal Energy Regulatory Commission to approve a set of proposed reliability requirements for large loads, including ramping and ride-through specifications. The proposal was published September 1, 2026.

MISO defines "large loads" as those above 50 MW and "computational loads" as large loads that include at least 25 MW of demand from information technology equipment, according to Utility Dive.

The interconnection reliability requirements framework aims to improve MISO's visibility into large load characteristics and behavior, support reliable planning and operational decision-making, and establish scalable expectations proportional to demonstrated reliability risk, according to Utility Dive.

The proposal is part of MISO's response to FERC's mid-June "show cause" orders requiring major grid operators to set rules that meet certain criteria for adding data centers and other large loads to the grid, according to Utility Dive. MISO said it plans to make additional proposals by a Nov. 16 deadline.

MISO runs the grid and wholesale power markets from Louisiana to Minnesota, according to Utility Dive. MISO's proposal follows similar actions at the Electric Reliability Council of Texas and the PJM Interconnection aimed at setting reliability standards for large loads after several incidents where data centers suddenly tripped offline, according to Utility Dive.

According to Energy News Beat, PJM is now considering ride-through requirements so data centers stay connected during minor disturbances rather than dropping off en masse. In extreme cases, operators may curtail large loads that lack their own contracted supply to protect residential customers, according to Energy News Beat. Texas lawmakers already granted ERCOT similar curtailment authority over new large loads to prevent emergencies, according to Energy News Beat.

What utility executives say about 2027

According to Energy News Beat, Exelon CEO Calvin Butler, whose company serves more than 10 million customers in the Northeast and Midwest including PJM territory, warned in June 2026 that Americans could "absolutely" face power losses as early as 2027 due to plant shortages and surging demand.

He noted the region came close to curtailing hundreds of thousands of customers during recent winter peaks, according to Energy News Beat. PJM has projected significant capacity shortfalls and is running emergency auctions while exploring backstop measures, according to Energy News Beat.

According to Utility Dive, MISO asked FERC to let its proposal take effect on Dec. 4, with grandfathering provisions to provide certainty to existing and nearly complete commercial arrangements for large loads. MISO also plans additional filings covering transmission products, study processes, protections against cost shifts, and treatment of generation service to electrically proximate large loads, according to Utility Dive.

According to Energy-Storage.News, industry experts anticipate that NERC's initial steps will evolve into formal requirements similar to those developed for renewable energy interconnections over the past decade. Dr. Ghaffarzadeh predicted more standardized or mandatory packages for dynamic studies starting from design through commissioning, according to Energy-Storage.News.

How households are told to prepare

According to Energy News Beat, the Edison Electric Institute and individual utilities continue standard storm and wildfire preparedness messaging: update contact information for outage alerts, stock emergency kits, and plan for medical needs.

Western utilities use Public Safety Power Shutoffs during high wildfire risk, according to Energy News Beat. Households in those areas are told to track shutoff notices through utility outage alerts and local providers.

The September 7, 2026, Energy News Beat report recommends a hybrid mix for homes, noting the amount of power needed to run a refrigerator, a freezer, heat, and cooking, and planning for several weeks of water. It also describes professional installation or packaged battery systems paired with gasoline, natural gas, or propane systems, and notes Generac systems that plug into natural gas or large propane tanks.

For extended outages, keep refrigerator, freezer, heat, and cooking needs in the plan and maintain emergency water supplies, consistent with the utility guidance summarized by Energy News Beat. Update outage-alert contacts before storm season, keep kits ready, and account for medical devices that need power.

Sources referenced