Cool, Clean Air

Editor’s Note: Ah, the deep days of summer. Time for sandals, sunscreen, iced tea in tall glasses–and cranking up that air conditioner a notch. Sure, you could do that, say Kim McKay and Jenny Bonnin, authors of True Green: 100 Everyday Ways You Can Contribute to a Healthier Planet (National Geographic, 2006). But U.S. home heating and cooling systems dump 150 million tons of greenhouse gases into the environment every year, and running those systems costs a lot, too.

Culled from McKay and Bonnin’s collection (based on their experiences with Clean Up the World, a global environmental campaign), here are some suggestions for getting through summer sans AC, no sweat.

Join the fan club. When a house is built for size and view, good passive solar design and orientation are often ignored–and the result is a heat trap (or, in winter, a cold dwelling). If you’re among those who live in a well-designed home, your abode should need nothing more energy-intensive than a ceiling fan. Even if your home design isn’t ideal, consider a whole-house fan or evaporative cooler. If you must use an air conditioner, set it to a balmy 81 degrees Fahrenheit rather than 75 and you will reduce energy use by nearly a third. Keep your ceiling fan on–it will improve your air conditioner’s efficiency.

Seal the cracks. Every degree of difference in the temperature between the inside and outside of your home can add as much as 10 percent to your heating and cooling expenses. Make the most of the energy you do use by trapping air rather than letting it escape through cracks under doors, between windows, and around floor vents. You can cut greenhouse gas emissions by more than 1,000 pounds a year just by using inexpensive seals to caulk and plug cracks and gaps, fitting dampers to fireplaces, blocking unnecessary vents, and weather-stripping all seams. Go to to learn more about tax credits for improving home efficiency.
Get cozy. Even in August. Heating and cooling your home accounts for up to 50 percent of your household’s energy bills, and air leakage alone accounts for 10 percent or more. Insulation material made from cellulose, fiberglass, foam, recycled paper, or straw can keep a home comfortable year-round, minimizing the need for heaters in the winter and air conditioners in the summer, and reducing your annual heating and cooling costs by up to 30 percent.

Make a curtain call. Cut heat transfer through windows by a third by installing heavy, lined drapes with pelmets or valances. Wooden frames provide better insulation than aluminum. Shade east- and west-facing windows with blinds or shutters. Cover south-facing windows with suitably angled eaves or awnings that provide shade during summer and light during winter. Choose glass appropriate to orientation and climate. Many Americans live in climates where glass technology can help save energy throughout the year, regardless of which direction their home faces.

Consider going glazed. Windows are the weakest link in a well-insulated home; a square yard of conventional single-pane glass exposed to direct sun on a hot day generates as much heat as an electric space heater. Double-glazed windows–two sheets of glass with air or gas sealed between them–are up to twice as expensive, but also twice as efficient. Look for an outer pane that will block unwanted solar radiation and an inner pane that will reduce heat transfer. Energy-efficient windows can lower your heating and cooling costs by up to 35 percent each year, and substantial tax credits are available.

Get your leafy greens. Plants not only lower greenhouse gas emissions and provide habitats for wildlife; they can lower home energy costs. Trees with high canopies on the west side of your property will provide shade from the afternoon sun. Shrubs that allow filtered light and breezes are appropriate for east- and west-facing windows. Deciduous trees and vines are useful on your home’s southern side, providing foliage to shade against the summer sun, while allowing light and warmth during winter. Be sure to shade your air-conditioning unit. You can enjoy significant yearly savings in home heating and cooling costs just by landscaping wisely.

Excerpted from the book True Green: 100 Everyday Ways You Can Contribute to a Healthier Planet, published by National Geographic; Copyright © 2006 True Green (Global) Pty Ltd. For more ideas, visit

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