https://www.vox.com/recode/2022/8/10/23300032/air-conditioner-planet-climate-change-heat-pumps

The AC is about a century old. What comes next?

Amid a growing number of heat waves, air conditioners have become a lifeline. Because these appliances are critical to keeping people cool — and protecting them from dangerously hot weather — the International Energy Agency (IEA) estimates that there may be more than 5 billion air conditioners across the planet by 2050. The problem is that while air conditioners do keep people safe, they’re also a major contributor to climate change.