If you're like most Americans during the hot summer months, your response is basically to crank up the air conditioning. Which is wonderful, except for a few issues being discussed on the New York Times "Room for Debate" page. For instance, that "the demand for coolant gases, especially in rapidly developing countries like India, threatens to accelerate global warming." Or, as author Stan Cox points out:
Cooling of America's buildings and vehicles has the annual global-warming impact of almost half a billion metric tons of carbon dioxide. (Three-fourths of that is attributable to fossil fuels, the rest to refrigerants.) We consume more energy for residential air-conditioning than do all other countries combined, but that's about to change. Home-cooling demand worldwide is projected to increase tenfold before 2050, stimulated by rising incomes and rising temperatures in already-warm regions. Such staggering growth will swamp out efficiency gains, outstrip renewable energy and accelerate warming.
So, if air conditioning is (highly) problematic from an energy and environmental perspective, what are the alternatives? One idea, raised by Amy Norquist of sustainable design/construction company Greensulate, is to "focus on reducing demand, consumption and providing renewable alternatives for cooling needs whenever possible." That includes technologies like "green roofs" and "white roofs," which can reduce the temperature on the roof "by as much 80 degrees for a green roof and more than 30 degrees for a white roof, [meaning that] HVAC technology can operate more efficiently" and that, of course, the building uses a lot less energy and creates a lot less pollution than it otherwise would have done.
Another great idea, this time by University of Washington architecture professor Steven Badanes, is to return to the ways we used to do things: "carefully orienting and shading buildings so that they gained heat in winter and were shady in summer, introducing thermal mass in dry climates, and in more humid ones using cross ventilation, porches, shutters, ceiling fans, solar chimneys and insulation." These "passive strategies," Badanes argues, "reduce the need for cooling," making it easier for "modern technologies like photovoltaics, daylight integrated lighting and smart controls [to] bridge the gap to a more sustainable future."
We'd also point to elegant alternatives like the deep lake water cooling system being operated in Toronto. This system "draws water from Lake Ontario through tubes extending 5 kilometres (3.1 mi) into the lake, reaching to a depth of 83 metres (272 ft)," as part of an "integrated district cooling system that covers Toronto's financial district, and has a cooling power of 59,000 tons (207 MW)." In conjunction with more efficient buildings (or, ultimately, zero-energy ones), solutions like this can keep us comfortable, while minimizing use of fossil fuels, emissions of greenhouse gases, and energy costs over the long term. Or, we could just keep on doing what we've always done, and expect different results. Of course, we know what Albert Einstein said about that idea...