Chill! (Or don’t.)

It’s summer. It’s hot out. And humid. And in my condo, in the background, pretty much 24/7, my A/C is humming along.

If you live in a city that gets hot – and humid – in the summer, and you’re not in a standalone house on a hill surrounded by trees, you really can’t live without it. Literally.

My mother grew up in Chicago, and she told us more than once that, during a heat wave, the newspapers would publish lists of those who had died.

My mother’s family was fortunate. They lived in a bungalow in the leafy reaches of the North Side, Not in a dense, tenement.  Even in that bungalow, leaves and all, I can guarantee you that it was broiling when, sweaty and grasping for air, you tried to get to sleep on that bungalow’s second floor during July.

Lucky for us, on our every-other-year vacations to Chicago, we only spent a few days (and nights) in the city before heading out to my grandmother’s vacation house (called “The Country”) on the appropriately named Sand Lake, up toward the Wisconsin border. Where it was a lot cooler.

We didn’t grow up with air conditioning in Worcester, either.

But our house was freestanding. On a hill. With lots of trees.

Even there and then, there were plenty of toss and turn nights. When we were kids, we often slept on The Porch, an addition that had been bolted on to our compact ranch house after the arrival of my surprise-baby sister. The Porch began life as, well, a porch: three sides of screens in the summer and glassed in (but unheated in the winter). That mode didn’t last long, and The Porch became what would now be called a Great Room or Family Room: a combo dining and TV watching and general hanging out locus. The Porch was furnished with two fold-down (not pullout) couches that converted to double beds. A boys bed and a girls bed, when we were little. It worked. It was breezy and sleep-able. As we got older, we migrated back to our stuffy, hot box bedrooms. But, because we weren’t in a tenement in the heart of the city, and were on a hill, in the shade, there weren’t that many really dreadful nights. And we always had the option of The Porch.

Eventually, my mother did get herself an A/C for her bedroom. Sleeping in the heat doesn’t age well. As we saw a few years ago when a heat wave in France – where air conditioning is rare – killed thousands of elderly folks. I understand it’s not a terrible way to die. Something to keep in mind…

That said, I’m not quite ready to turn the A/C down and drift off into Big Sleep.

So, the A/C stays on. And on. And on.

But the other day, Penelope Green, writing in The New York Times, asked a provocative question: Do Americans Need Air-Conditioning?

Although my answer is, yes, in fact we do, Green makes some good points.

Offices can definitely be overcooled. No need to have them cooled so that it’s only comfortable if you have a suitcoat on.

She doesn’t mention restaurants or movie theaters, but I never go out in summer without some sort of schmatta to throw over my shoulders in case the temp is set to 62 degrees.

So far, by the way, the cooling battles, the thermostat settings, have been won by men, who on balance like temperatures cooler than women do.

Turning the thermostat up a bit is one thing, but there’s other things we could be doing.

I’m quite sure that buildings could be made more efficient on both the heating and cooling fronts. They oughta be, given the impact heating and cooling have on the environment.

But sometimes the building thing can go too far.

A few years ago, an architectural firm in Philadelphia reno’d a new space for themselves and got rid of AC.

Passive and active features provided the cooling, like mechanical and natural ventilation (fans and windows that opened); automated shades; insulation, including a concrete slab floor; and dehumidifiers. The design thinking behind these contemporary refinements has worked for millenniums — imagine an adobe house, or a Roman villa, sealed and shaded against the day’s heat, and opened up at night.

Unfortunately, the employees hated it.

More fans and pushing folks to get to work earlier and dress more casually didn’t quite do the trick. So the firm had to add some traditional A/C to be deployed as needed. Still, the building “is a model of energy efficiency.”

There are things that can be done beyond concrete slab floors and automated shades.

So I’m delighted that MIT’s Neri Oxman “and her colleagues are developing self-cooling building facades and clothing.”

At M.I.T., Dr. Oxman’s team is experimenting with polymers and bacteria in the hopes they might “grow” building facades, and “wearables” — clothing, for example — complete with arteries to hold cooled liquids or gas. They can already 3-D-print glass structures with “spatial pockets” designed to be filled with cooling liquid, as well as “biocompatible synthetic skins” for bodies and buildings, Dr. Oxman said, which would “act as thermodynamic, environmentally sensitive filters and barriers” to respond to temperature changes in the environment and self-regulate.

Yay, scientists! Yay, MIT!

Let’s get moving on those “biocompatible synthetic skins.” I could have used one the other day working in the kitchen at St. Francis House. If you can’t stand the heat, you don’t want to be doling out chicken corn chowder when it’s 90 degrees out.

And speaking of 90, I found it interesting that “nearly 90 percent of American households now have some form of air-conditioning,” the highest proportion of any country other than Japan. A lot of these, I’m sure, are folks in the leafy-shady burbs or cool and comfy country who only need A/C a few times a year, when things are truly unbearable. Still, that’s a pretty stunning figure. As the planet heats up, places that have done without – like Europe – will likely be clamoring for more A/C, not to mention places like India where more people are being more affluent and urban, and the country is heating up beyond what folks have become acclimated to over the centuries.

Meanwhile, I’m keeping my A/C on, thank you.