100°F Prison Cells: 10+ Hotter Days Fuel Inmate Heat Deaths

Climate adaptation isn't only about seawalls and wildfire buffers—it's also about whether prison cells remain survivable during heat waves. At San Quentin, America's oldest prison, an eight-hour outage in 2024 pushed indoor temperatures to 100°F with no AC, ice, or cold water. For climate and energy professionals, the failure to cool carceral facilities is a measurable infrastructure gap with rising legal and humanitarian costs.

America's aging prison infrastructure is emerging as a lethal failure point in the climate crisis. Reporting from San Quentin Rehabilitation Center, California's oldest prison, documents how incarcerated people like Steve Brooks endure cell temperatures between 90 and 100 degrees Fahrenheit during an eight-hour power outage in 2024, with no air conditioning, no ice, and no cold water. Brooks, who writes about extreme heat behind bars, describes the sensation as hyperventilating, the room closing in, and running out of oxygen. These conditions are not isolated. Researchers at the Massachusetts Institute of Technology found that most U.S. prisons experienced at least 10 days in a single summer that were hotter than every previous summer, and that overcrowding, heat-trapping construction materials, and a prison boom that began in the 1970s compound the danger.

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Damon Gilbert, a fellow at New York Lawyers for the Public Interest, said heat-related deaths in prisons are underreported and that the country is 'not keeping up' with adapting these facilities.

The physiology of extreme heat is well understood: extreme heat can cause dizziness, nausea, and headaches, while heat stroke is the most serious heat illness and can kill. High humidity slows sweat evaporation, making it harder for the body to cool itself. For prisoners with chronic conditions such as diabetes, cardiovascular disease, kidney disease, or mental illness, even lower temperatures can destabilize health or become fatal. Damon Gilbert, a fellow at New York Lawyers for the Public Interest, said heat-related deaths in prisons are underreported and that the country is 'not keeping up' with adapting these facilities. That underreporting matters because official mortality data underestimates the true burden and may mask heat-linked suicides and other deaths.

The structural roots are decades old. Many U.S. prisons and detention centers were built during the prison construction boom that started in the 1970s, using concrete and steel that absorb and re-radiate heat. They often lack modern cooling systems or have units that are inefficient or nonfunctional. Overcrowding compounds the problem: more bodies in confined spaces raise indoor temperatures and strain electrical systems, and periodic power outages disable fans and any evaporative cooling, turning cells into ovens. Brooks' reliance on two eight-inch fans illustrates the precarious baseline.