For years, I have been going on about how and why we should live without air conditioning. There are dozens of posts talking about ways to beat the heat without AC. About how to dress, when to eat, what to eat. And most importantly, how it is all about design. I would quote professor Cameron Tonkinwise of Carnegie Mellon School of Design: "The air conditioner allows architects to be lazy. We don't have to think about making a building work, because you can just buy a box."
But things are changing. I have always written that air conditioning is a response to a design problem, the way we design our cities and our homes. I recommended big windows with cross-ventilation, high ceilings, walls with tons of thermal mass. However the Passive House experts approach the problem from a different angle: they use super-insulation, high quality windows, and mechanical ventilation to create an envelope that needs almost no heat or cooling at all to maintain a comfortable interior temperature. The Net Zero people are piling enough solar panels on the roof to run the AC, changing the old "We're cooking our planet to refrigerate the diminishing part that's still habitable" trope I have been quoting since 2006.
In February (why then, I have no idea) I wrote in MNN about how technology was changing in ways that might solve our problems; looking at the growth of solar power, passive houses and electric cars, I wondered if my previous prescriptions of a city without cars and homes without air conditioning still made sense.
I don’t think that's realistic anymore, given that so many people live in the South and Southwest now, places where it is almost impossible to live without air conditioning. Our summers have become hotter, and we have become used to being in a cocoon of cool air as we move from house to car to office.
Also, encouraging people to live without air conditioning is less relevant with the increasing popularity of super-insulated homes like the Passive House, which don’t need much air conditioning at all; it doesn’t take much to get them cool and keep it there.
Let's be realistic about the rest of America too, it's getting unbearably hot in New York City and Toronto now. In my own house, with its brick walls and cross ventilation and big tree providing shade, my daughter needs an air conditioner to survive on the third floor. I could say "sleep on the porch" like people did a hundred years ago, but that doesn't work anymore when there are alternatives that let one stay in their own room. People are not willing to go through the hell they did in New York just sixty years ago, sleeping in parks with their alarm clocks beside them in the grass.
Over at the Resilient Design Institute, Alex Wilson comes to the same conclusion writing In an Age of Climate Change, Passive Cooling Won’t be Enough
Rising temperatures and increasing cooling loads argue, first of all, for redoubling our efforts to incorporate high levels of insulation, cooling-load-avoidance measures, and passive cooling strategies into our buildings. This is particularly important given the prospect of increased risk of power outages during heat waves—as we saw in western France a few weeks ago....Yes, we need to keep doing all that—and doing it better—but we should also be thinking about incorporating efficient mechanical cooling systems.
Fortunately, if you apply the passive strategies first, the active heating and cooling components become really dinky and inexpensive; Alex heats and cools his super-insulated house with an off-the-shelf mini-split air source heat pump.
I have written before that air conditioners are like cars; they have changed our lives and we have built our cities around them. Our houses and modern apartments are designed in such ways that they would be uninhabitable without air conditioning, as uninhabitable as our suburbs are without cars. The climate is changing and just making it hotter and harder to live without AC.
So I am not going to talk as much about living like Grandma; it was never realistic for most people. In MNN, I concluded that it is still all about design. Yes, learn from the past, but be realistic about the technologies that we can use today.
We need a balance between the old and the new, an understanding of how people lived before the thermostat age along with a real understanding of building science today. To discover what we have to do to minimize our heating and air conditioning loads and maximize comfort, we have to design our homes right in the first place.
Then adding a little air conditioning won't be a problem for anyone.