Best Backyard Grills

*Wood: Harvesting it can contribute to deforestation, and grilling it releases ash and smoke, which provoke respiratory problems. Consider slow-burning hardwoods like fast-growing mesquite, kiawe and hickory over pine and other fast-burning softwoods.

*Charcoal: Releases more greenhouse gases than wood, can cause even greater deforestation and produces ground-level ozone. The Cowboy Charcoal Co. (www.cowboycharcoal.com) makes low-smoke charcoal out of untreated maple and oak scraps from furniture and flooring plants; also available at Whole Foods (www.wholefoods.com).

*Avoid lighter fuel and self-lighting briquettes, which give off petrochemical volatile organic compounds. Instead, set briquettes on top of a small amount of burning paper or try a chimney starter, a cylinder that uses lit newspaper.

*Gas grilling is one of the most energy-efficient methods and, if you use natural gas, the cleanest-burning fossil fuel, you'll release fewer harmful pollutants. Try the sturdy Vermont Castings VCS 3006 gas grill ($449; www.myownbbq.com, 800-525-1898).

*Electric grills are also much safer, emitting 99 percent less carbon monoxide than charcoal grills. They also reduce carbon dioxide emissions by 91 percent over charcoal and 21 percent over propane.