My house doesn’t have air conditioning. I don’t miss it. Occasionally there’s a day or two where it’s a bit uncomfortable. On those days, my strategy is to grab a cold beer and wade into the lake. It works for me.
The current heat wave isn’t hitting northern NH too badly. It’s not even supposed to get to 90 before cooling off early next week. It still gets down to the 50s and 60s at night, so it’s possible to have a comfortable night’s sleep.
Air conditioning is a wonderful invention. It’s made the south livable. Old southern architecture, in the days before AC: high ceilings, good cross ventilation, big shaded porches, but when it gets really hot, it’s hot. AC makes even a tin box mobile home comfortable. New houses aren’t designed to use natural cooling and without AC they are unlivable.
In northern NH we don’t worry so much about staying cool. Keeping from freezing to death half the year is the main concern. At least it’s possible to stay warm using fairly primitive methods. Pile on the clothes and blankets. Burn wood in a woodstove. In the old days, a serviceable fireplace could be built using rocks and clay.
There is no primitive AC. Sure, there are swamp coolers that work if the humidity is low enough, fans help, earth tubes and earth sheltered construction can be effective. That being said, there is no easy retrofit for a modern AC unit. Many homes in the north have added wood heat without too much trouble. There’s no plug in substitute for AC. Whether it’s heating or cooling, having one really comfortable room is a relief -necessary for people with health issues.
Heat waves currently cause a certain number of deaths. If the grid goes down at the same time, there’ll be a lot more. Plenty of people aren’t acclimated to hot temperatures. My sister-in-law in TX didn’t even know there was a heatwave one year. She went from AC house, to AC car to AC office.
Most people can adapt to warmer temperatures, but it takes some exposure to them. You can’t go from a constant 70 degree AC environment to 100 degree temps. When my wife and I go to the the south, we try and stay out of AC as much as possible to adapt. There’s no AC in our old truck, and we often camp in tents or on the sailboat. We drink plenty of water and take it easy until we adjust. For me, it takes about two weeks, but it’s worth it. After that, it’s fun in the sun.