More than 1.3 million utility customers across a swath of states from Oklahoma to Connecticut lost power during the July 4, 2026, heat wave, and for the vast majority of those customers, the experience was a hardship. But for the estimated 3 million or more Americans who depend on electrically powered home medical equipment, the outage was something categorically different: a compounded medical emergency in which dangerous external heat and loss of essential life-support equipment converged simultaneously.
According to NBC News and PowerOutage.us, Michigan led the outage count with more than 305,000 customers in the dark; New Jersey followed with more than 124,000; Pennsylvania exceeded 151,700; and Missouri reported more than 100,000 without power. Total outages exceeded 1.3 million on July 4 and climbed toward 900,000 the following day as additional storm systems moved through.
In New Jersey — where 25 people are suspected to have died from heat — state Health Commissioner Dr. Raynard Washington confirmed that resources, including chillers and generators, were being dispatched to healthcare facilities "in distress." "In some cases, where we have to, we are working to evacuate patients from facilities where necessary," he said at a July 4 press conference.
Why This Matters
For most people, a power outage in a heat wave is dangerous because the home grows hot without air conditioning. For people on home medical equipment, the risk is doubled: heat is threatening from outside while loss of equipment is threatening from within.
Research published by the University of California, Irvine, and the University of Tennessee found that most home medical devices run on backup batteries lasting only 3 to 8 hours — but people in more than half of U.S. counties experienced at least one outage lasting longer than 8 hours between 2018 and 2021. Power outages are becoming more frequent and longer, up 9% more frequent and lasting 56% longer between 2014 and 2023.
The combination is what makes this population particularly vulnerable in this specific event. At 95°F outdoor temperatures with no air conditioning, an interior can reach dangerous body-temperature threshold levels within one to two hours. An oxygen concentrator that runs out of battery at hour three adds a respiratory emergency on top of the heat emergency.
What We Know So Far
From NBC News, ABC News, ABC News energy emergency coverage, and PowerOutage.us:
- Total outages July 4 : More than 1.3 million utility customers across a diagonal swath from Oklahoma to Connecticut
- State totals : Michigan 305,000+; Pennsylvania 151,700+; New Jersey 124,000+; Missouri 100,000+; plus outages in Georgia, New York, Ohio, Virginia, Tennessee, and others
- Home medical equipment users : An estimated 3+ million Americans rely on electrically powered home medical devices
- New Jersey health resources deployed : Chillers and generators sent to healthcare facilities "in distress" ; patient evacuations occurring at some facilities
- Most home medical device backup batteries : 3 to 8 hours of runtime
- Most vulnerable : The subset of low-income urban renters with medical devices who also lack air conditioning and backup resources — disproportionately Black and Hispanic, per UC Irvine research
Who Depends on Home Medical Equipment?
Major categories of life-dependent home medical equipment include:
- Oxygen concentrators — used by patients with COPD, pulmonary fibrosis, and severe heart failure. Portable units typically have 4 to 8 hours of battery life; stationary concentrators have no battery and require power at all times
- Home ventilators — for patients with ALS, spinal cord injury, muscular dystrophy, or severe respiratory failure
- CPAP/BiPAP machines — used by millions with sleep apnea; generally not immediately life-threatening if lost for a single night, but impairful for patients with severe apnea
- Insulin refrigeration — insulin degrades rapidly above 77°F to 86°F; a power outage of more than a few hours threatens the viability of a diabetic patient's insulin supply
- Infusion pumps — used for IV medications including antibiotics, chemotherapy, and pain management
- Electrically powered wheelchairs — loss of power renders these devices immobile, trapping users
Where the Risk Is Highest
Based on the July 4–5 outage distribution:
- Michigan : More than 305,000 customers — particularly concerning in the Detroit metropolitan area, where the aging housing stock and high proportion of elderly residents in inner-ring suburbs create layered vulnerability
- New Jersey : 124,000+ customers in a state that has already confirmed 25 heat-related deaths — the co-occurrence of heat fatalities and power loss is exactly the compounded emergency scenario researchers have warned about
- Pennsylvania : 151,700+ customers — Philadelphia area hospitals were already operating under extreme heat stress
What Officials and Experts Say
"Maintaining affordable, reliable, and secure power in the PJM service territory is non-negotiable," said Energy Secretary Chris Wright in the emergency order authorizing PJM emergency operations. The emergency orders specifically cited ensuring "essential operations like hospitals are fully functioning during the heat wave" as a priority.
What the grid emergency orders cannot address is the individual residential vulnerability of millions of Americans on home medical equipment — a gap that university researchers have documented extensively and that advocacy organizations for older adults and people with disabilities have repeatedly flagged.
What the Evidence Shows — and What It Does Not
The 1.3 million outage figure is confirmed by PowerOutage.us real-time tracking. The 3+ million home medical equipment user estimate is drawn from utility medical baseline program data and healthcare utilization research. The specific mortality consequences of the July 4 outages for medical equipment users have not yet been tallied — heat wave mortality investigations take weeks to complete.
Who Faces the Greatest Risk?
Based on the UC Irvine/UT research on home medical device users and energy insecurity:
- Low-income renters with medical devices who lack AC, backup power, and financial resources to address power disruptions
- Older adults on oxygen or ventilator support living alone
- Patients with insulin-dependent diabetes whose insulin may have been rendered ineffective by the outage
- Rural patients with medical equipment who are furthest from emergency response and cooling centers
Symptoms and Warning Signs to Watch For
For oxygen-dependent patients during an outage:
- Increasing shortness of breath or labored breathing
- Bluish tinge to lips or fingernails (cyanosis) — a sign of oxygen deprivation
- Rapid heart rate or confusion
- These symptoms require immediate 911 contact — do not wait
For insulin-dependent diabetics:
- Unusually high blood glucose readings after using insulin stored during the outage
- Signs of diabetic ketoacidosis: nausea, vomiting, abdominal pain, fruity breath, rapid breathing
What You Can Do Now — The Single Most Important Preparedness Step
Register with your utility as a "life support" or "medical baseline" customer — today.
Every major U.S. electric utility has a medical priority program. Registration provides:
- Priority power restoration — your household is flagged for faster service restoration during outages
- Advance notice of planned outages — giving time to arrange backup power or temporary relocation
- Protection from service disconnection during declared heat or medical emergencies
In New York: call Con Edison at 1-800-752-6633. In New Jersey: call your utility company. In Michigan: contact DTE Energy or Consumers Energy. In Pennsylvania: contact PECO or PPL Electric.
Beyond registration:
- Develop an emergency plan that identifies: the nearest hospital, a family member or neighbor with power, and a cooling center that can accommodate your medical needs.
- Maintain backup battery power for your most critical devices — portable power stations capable of running a CPAP, oxygen concentrator, or refrigerator are available at most electronics retailers.
- Keep insulin in an insulated case with ice during any threatened outage. If your insulin was stored at room temperature during an outage of more than two to four hours, verify with a pharmacist whether it remains viable.
- Call 911 if you are a dependent of powered medical equipment and have lost power with no battery backup. Most 911 systems can flag medical priority for restoration or dispatching emergency resources.
Cost and Access: What Patients Should Know
Utility medical priority registration is free and available from all regulated utilities in the affected states. Backup power stations range from $200 to $2,000+ depending on capacity; for patients on fixed incomes, some state energy assistance programs provide subsidies for medical backup power equipment.
The Low Income Home Energy Assistance Program (LIHEAP) provides direct financial assistance with utility costs and may provide emergency support during declared heat emergencies.
What Happens Next
New Jersey, Michigan, Pennsylvania, and other heavily affected states are conducting post-event assessments of heat wave mortality that will include an investigation of deaths among home medical equipment users. Utility companies are also conducting infrastructure assessments to identify equipment that failed under heat stress.
MedicalDaily will report on confirmed fatalities linked to power outage medical equipment loss as state reports are completed.
The Bottom Line
When 1.3 million customers lost power during the deadliest July 4 heat wave in over a decade, most of them faced discomfort. For the 3 million Americans who depend on powered medical equipment at home, the consequences were potentially life-threatening. The single most effective protective action available right now — registering with your utility as a medical priority customer — costs nothing and can save a life. If you or someone in your household depends on electrically powered medical equipment, make that call today.
