The other night I took my dogs out for a walk around 11pm: despite the fact it was pleasantly breezy and cool, the buzz and rattle of air conditioners came from all sides. My neighborhood, mostly three- to six-story buildings in Brooklyn, had switched into summer mode, and not noticed that the weather itself, at least after dark, was still behaving like spring. The rush to turn on the AC seems to come earlier every year, despite rising electricity costs and mounting evidence of the need to conserve energy.
Air conditioning is one of the biggest consumers of energy in this country, which is itself the largest consumer of energy in the world. One fifth of the energy we use goes to cooling buildings, and air conditioning contributes to global warming through both energy consumption and the inevitable release of refrigerants (aka greenhouse gases) used in the AC units. With six percent of the world’s population we consume 40 percent of the world refrigerants.
Here in New York, and all cities, air conditioning helps create the problem it purports to solve. AC units release heat, creating the urban heat island effect — the result of too much asphalt, too many vehicles, and too few trees. The heat island makes the city five to ten degrees hotter than the areas just outside of the city, and contributes mightily to greater AC use, energy consumption, air pollution, heat-related illness, and mortality. It’s a nasty cycle.
So what can you do to stay cool? Use a fan, or several. Install ceiling fans where you can. Take quick showers to cool off. Pay attention to your living space — keep windows and curtains open at night, then close them early to keep cooler air in and the heat out. Thicker drapes or light-reflecting window shades can really cut down on heat absorption, and are a lot cheaper than even a few days of running your air conditioner. Awnings and shutters, much in use in Europe, are effective and sustainable alternatives requiring a one-time, modest investment.
Remember that direct sunlight heats walls and roofs, which then radiate that heat for hours after the sun goes down (you’ve probably walked by a “hot” wall late some summer night). Any way that you can keep the sun off the outside of your place, or the sidewalk in front, will help: trees are the biggest and best shade casters, (they also transpire huge amounts of water, which helps cool things down). If there’s space for one on your block, contact the city — it might take a while but they will come and plant trees if you request them. Plenty of smaller plants can help, too. A couple of morning glories on a fire escape can cast a lot of shade; some ivy can permanently shade a large area of wall or patio. Get together with neighbors and coordinate some plantings to cover and cool your building.
Green roofs, with waterproof membranes covered by lightweight soil and a layer of plants, are incredibly effective insulators and reduce the need for both heat in the winter and AC in the summer. They also clean the air, absorb rain water in a way that helps control flooding and runoff, and provide some habitat for birds. If we were really serious about the environment, green roofs would be mandatory for EVERY new building and renovation in the city:
Air conditioning contributes to global warming through
both energy consumption and the inevitable release of refrigerants.
of course they cost more up front, but like so many other environmental innovations, they more than pay for themselves in the long run.
Most importantly, try to modify your routine, and your expectations, and remember that most of humanity still lives without AC. Do as your grandparents did: do less in the middle of the day, congregate on your stoop in the evening, or go to a restaurant with a patio or garden. Wear sandals and natural fibers, carry a hand fan, and cut your hair. If you really can’t live without the cool, try spending time at a café or bar, sharing a communal air conditioner rather than running the one at your place. What you spend on iced lattes you may save on Con Ed.