The air conditioning paradox: How staying cool makes it hotter

Turning down the thermostat is turning up climate change

June 16, 2021 7:29 am

Ain’t nobody got the words like a Southerner when it comes to heat waves — and this week, there’s gonna be a whole lotta hens layin’ hard boiled eggs.

But before you reach for the thermostat, think twice. Every degree you turn it down, you’re turning up the dial on climate change.

The air conditioning paradox is cruel. No one thinks about 10 years out while sweatin’ like a hog. Yet thinking ahead is exactly what addressing climate change requires us to do.

The problem with AC is two-fold.


The first issue is hydrofluorocarbons. Hydrofluorocarbons are chemical compounds used as refrigerants in cooling systems including air conditioning. Like carbon dioxide, HFCs are greenhouse gases, meaning they trap heat when in the atmosphere and contribute to climate change. Although these compounds make up significantly less of the greenhouse gasses than CO2, HFCs are many thousand times more potent at trapping heat, meaning they accelerate climate much more quickly, even in small amounts.

When contained properly in cooling systems, HFCs can be used for cooling without too much guilt. However, if there is a leak, or if a unit is disposed of improperly, these compounds can quickly escape into the atmosphere and wreak havoc. With millions of AC units in use, these effects add up more than one might suspect.

Based on current levels of HFC use in the United States, the Environmental Protection Agency estimates total HFC emissions could equate to more than 4.7 billion metric tons of CO2 by 2050. This is roughly the equivalent of three full years of U.S. power sector emissions based on 2019 levels. Thankfully, as of May 3, the EPA has moved to reverse a Trump-era policy, and is now working under President Joe Biden’s administration to reduce HFCs by 85% over the next 15 years. Still, if you have a model with a leak using HFCs, you’ll want to get it fixed or replaced immediately.

The second concern with AC use is energy consumption, and this is the crux of the paradox.

As climate change continues to drive temperatures hotter than the hinges of Hades’ gates, the energy required to use air conditioners — even units without HFCs — increases dramatically. Given our current grid infrastructure is nowhere close to fully renewable, this means we’re using more fossil fuels every time we reach for the “on” switch. Of course, the increased use of fossil fuels further drives climate change, making temperatures even hotter, which in turn requires more air conditioning, thereby using more energy. This loop continues ad nauseum, until eventually it’s so hot they’d say cows give evaporated milk. Not even a sweet iced tea can fix that one.

Energy consumption is also problematic in that as we transition to a fully renewable grid, it requires not only producing enough energy to meet current demands, but actually expanding energy capacities for the anticipated increased demands as energy consumption continues to rise for extreme temperatures. Especially as many existing buildings do not have built-in air conditioning systems, more units will be installed, further increasing consumption. Given we all use the energy at the same time — when it’s hot — the rate at which we consume energy could easily extend well beyond our current grid capacities. One need look no further than the Texas electrical grid this week for an example.

If you’re thinking the AC paradox will disproportionately impact disadvantaged communities, you’re right, and for multiple reasons. For starters, in many states, landlords are not required to provide air conditioning — even in climates hotter than the dickens. This risks the health of tenants who can’t afford to buy. At the same time, the cost of increased cooling is also an issue, and those who can’t afford to better insulate or upgrade cooling systems will be most impacted.

All this isn’t to say you shouldn’t turn on your AC — you almost certainly must. Still, we should all be aware of how often we use it, when we use it and especially how to properly fix leaks or dispose of units as needed so as to avoid further exacerbating the problem.


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Trish Zornio
Trish Zornio

Trish Zornio is a scientist, lecturer and writer who has worked at some of the nation's top universities and hospitals. She’s an avid rock climber and was a 2020 candidate for the U.S. Senate in Colorado.