As someone who enjoys cooking in the great outdoors, albeit a rowhouse backyard, I wondered about the environmental impact of firing up my barbecue cooker.
I read reports and interviewed people who have addressed various aspects of green grilling.
Right away, I struggled with the question of scale. By one federal government estimate, all the barbecue grills in America fired up on July 4 produce only .003 percent of the nation's annual total carbon dioxide. So whatever I do in my backyard grill does not rival the environmental impact of, say, flying a jet from Baltimore to Boston.
But individual acts do matter, both in a cumulative sense and in changing a mind-set. So I plowed on.
It turns out that the environmental impact of backyard grilling is hazy. Take the matter of fuel, of grilling a burger over charcoal or gas. I am a confirmed fan of charcoal fires. I like the smoke flavor they produce and the crust they can put on meat and fish. I have cooked with gas, but only under duress. Somehow, the steaks cooked on gas just don't sizzle for me.
Both fuels produce some greenhouse gases, according to the Environmental Protection Agency. But the carbon dioxide produced by charcoal is considered to be coming from a "natural" source and is not included in the inventory of greenhouse gas emissions.
The carbon dioxide from burning propane, however, falls into the man-made category, and is tallied.
Using the greenhouse gas calculator on the EPA Web site, I saw that to produce the equivalent of a ton of carbon dioxide, I would have to burn almost 38 propane cylinders. That is a lot of grilling.
Tris West, an environmental scientist at Oak Ridge National Laboratories in Oak Ridge, Tenn., told me that the main advantage charcoal has over gas is that charcoal is made from trees.
West, who conducts research in carbon accounting, explained that the trees that produced the charcoal swallowed carbon in the atmosphere as they grew. The cycle of trees swallowing carbon, then burning the tree-produced charcoal, comes close to a net zero in carbon emissions, he said.
Rick Browne, however, spoke up for gas. Browne is a Vancouver, Wash., author of barbecue books, producer of the Barbecue America television program and spokesman for several food products, including a line of gas grills.
Propane, he said, produces about one-third of the emissions per British thermal unit of charcoal briquettes. Moreover, Browne said, gas grills yield no ashes or other residues that require disposal.
I bounced Browne's emission numbers off West. West said you have to look at the big picture. If you fire up a gas grill and a charcoal grill next to each other in the backyard, the charcoal grill would, as Browne suggested, produce more emissions. But West said when you figured in charcoal's leafy-green heritage, its total carbon emissions drop to almost nothing.
My head was swimming in the nuances of emissions, so I switched the conversation to what kind of grill West cooks on. He said he cooks on both a gas and a charcoal grill.
"When I am cooking something longer, I use charcoal," he said. "When I cook something quickly, I use the gas grill."
Browne also said that he uses both gas and charcoal. He also offered me a tip on a cleaner way to start a charcoal fire. Usually, I put charcoal in a chimney starter, a metal device with a false bottom. I get the charcoal started by lighting a crumpled newspaper that I have stuffed under the false bottom of the chimney.
But a greener way to start the fire, Browne said, is to gather a large wad of cotton lint from the clothes dryer and stick it under the chimney. Not only will the charcoal catch fire, Browne said, but the process also gets rid of unwanted lint.
I will try to burn the lint the next time I grill burgers.
See Rob Kasper each Wednesday on ABC2/WMAR-TV's News at Noon.