What's the Best Way to Barbecue?

May 20, 2009 — -- Memorial Day is upon us, and the backyard grilling season is moving into full speed, giving rise once again to that hotly debated question: Which is best, charcoal or gas?

Setting taste aside for the moment, there is some evidence these days that if you think charcoal is less damaging to the environment you could be dead wrong.

A researcher in England has concluded that the carbon footprint for charcoal is about three times as big as the footprint from burning propane, the most common alternative to charcoal.

That's consistent with a study a few years ago from Oak Ridge National Laboratory, which looked at the impact from all those grills fired up on the most popular grilling day of the year, Independence Day.

That study concluded that enough energy would be burned on that single day to meet the residential demand of a city the size of Flagstaff, Ariz., with 21,000 households.

Those grills would emit nearly 225,000 metric tons of carbon dioxide, a greenhouse gas, the study concluded, especially since charcoal is the preferred fuel for nearly half of America's backyard chefs.

It will also burn the energy equivalent of 2,300 acres of forest.

The study argued that if the 34 million gas grills that were expected to be fired up for that day were instead fueled by charcoal, an additional 89,000 tons of carbon dioxide would be emitted. And if the charcoal grills could be switched to propane, carbon dioxide emissions could be reduced y 26 percent, or about 59,000 tons, the study found.

Case closed, right? Well, it's not all that simple.

In a study published in the current issue of Environmental Impact Assessment Review, environmental researcher Eric Johnson looked at all phases of the production, transportation and consumption of both propane and charcoal in the United Kingdom.

His findings were based partly on the fact that the charcoal consumed in England comes mainly from developing countries, especially Africa.

Much of the charcoal from those countries is produced in a pretty simple way -- trees are set on fire, buried under dirt, and left there until the wood has been reduced to dry carbon, the principal component of the stuff used in backyard grills.