The Economist suggests three things: Better machines, better refrigerants and better buildings.
This TreeHugger used to write that air conditioning was a response to really bad design, quoting Professor Cameron Tonkinwise who said “the window 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 as I wrote recently, the world has changed, and so have I, recognizing that I was being an elitist writing from a detached old house in a temperate climate. Most people are not so lucky. The Economist is following this trend, writing:
At the moment, only 8% of the 3bn people in the tropics have air-conditioning, compared with over 90% of households in America and Japan. But eventually, it will be near universal because so many trends are converging behind its spread: ageing, since old people are more vulnerable to heat stroke; urbanisation, since fields cannot be air-conditioned but offices and factories must be; and economic growth, since, after mobile phones, the middle class in emerging markets want fans or air-conditioners next.Lloyd Alter/ minisplits in Changsha/CC BY 2.0
But there is a huge carbon footprint to running all this AC; “At current rates, Saudi Arabia will be using more energy to run air-conditioners in 2030 than it now exports as oil.” International Energy Agency (IEA) figures that running AC now produces 4 billion tons of CO2 annually or 12 percent of the total.
In their leader to the AC story, How to make air conditioning more sustainable, the Economist notes that just doubling the efficiency of AC and changing the refrigerants could save more carbon than having half the world go vegetarian. But they claim that AC is not given the attention it deserves:
Air-conditioning is one of the world’s great overlooked industries. Automobiles and air-conditioners were invented at roughly the same time, and both have had a huge impact on where people live and work. Unlike cars, though, air-conditioners have drawn little criticism for their social impact, emissions or energy efficiency. Most hot countries do not have rules to govern their energy use. There is not even a common English word for “coolth” (the opposite of warmth).
This is absolutely true. It also points to a contradiction, since to get rid of cars we need greater urban density, which increases the temperature and the ambient noise, creating a need for more air conditioning. The Economist has three recommendations:
Raise minimum acceptable standards of efficiency. “The most energy-efficient models on the market today consume only about one-third as much electricity as average ones.”
Change to safer, less damaging refrigerants. “An international deal to phase out these pollutants, called the Kigali amendment, will come into force in 2019. Foot-draggers should ratify and implement it; America is one country that has not done so.” This is a whole other story, with a whole pile of right-wing anti-science organizations that have the ear of the President is lobbying against Kigali.
And here is perhaps the most important one:
Last, more could be done to design offices, malls and even cities so they do not need as many air-conditioners in the first place. More buildings should be built with overhanging roofs or balconies for shade, or with natural ventilation. Simply painting roofs white can help keep temperatures down.
This has been our mantra too, Reduce Demand! They list all the traditional measures that we have discussed. But it’s not enough; there have to be much higher standards for controlling heat gain through insulation, window sizing and quality for when the old ways can’t cope. That’s why their conclusion is so important:
Better machines are necessary. But cooling as an overall system needs to be improved if air-conditioning is to fulfill its promise to make people healthier, wealthier and wiser, without too high an environmental cost.
You can’t, as Cameron Tonkinwise put it, just add a box. You can’t, as the Rocky Mountain Institute suggests, just sell someone a new HVAC unit. It starts with urban design and goes right down to the detail of how you build a wall. We have to get away from boxes and think about overall systems, the bigger picture, or as William Saletan put it years ago, we will be “cooking our planet to refrigerate the diminishing part that's still habitable."