A greener flame
by Pamela Portwood
The smell of wood burning in a fireplace evokes scenes of family and friends gathered by the roaring fire, drinking hot cider and laughing while snow falls outside. (Of course, for desert natives the images often come from movies rather than memories.) The smell of wood smoke may be romantic, but it's not healthy or energy efficient.
Wood smoke is a combination of gases and particles. Inhaling the smoke's microscopic particles and getting them in your eyes causes more than coughing and burning eyes. Fine particle pollution has been linked to many health problems, including reduced lung function, increased asthma problems, the development of chronic bronchitis, nonfatal heart attacks and even premature death in people with heart or lung disease.
Premature death just takes the romance out of that smoky smell, especially since studies have shown that up to 70 percent of chimney smoke can reenter the home and nearby buildings.
As heating sources, fireplaces are notoriously ineffective, and they can reduce the interior heat by drawing warmed air up the flue. Traditional woodstoves do heat homes better than fireplaces, and EPA-certified woodstoves burn more gases and particles so that less smoke is released.
Below are some greener options for fireplaces and stoves. Federal tax credits are available now for some energy-efficient woodstoves purchased by Dec. 31. Check the Environmental Protection Agency's site for details: www.epa.gov/burnwise.
Ethanol fireplaces burn ethanol, which is produced by fermenting the sugar and starch of bio-based products, including sugarcane, corn and even grapes. Ethanol's only emissions are heat, steam and a small quantity of carbon dioxide. Ethanol fireplaces don't require a chimney or venting, so stylish, freestanding models are available although some of them are largely decorative.
Natural gas fireplaces burn cleanly and are economical. Gas fireplaces do not generate particulate matter, but they do produce some greenhouse gases, such as methane. Although vent-free gas fireplaces are available, both the EPA and the American Lung Association recommend using vented gas fireplaces to ensure good indoor air quality (IAQ). On the con side, gas is a non-renewable resource.
Electric fireplaces are like framed flames that you can hang virtually anywhere. Some models will run with or without heat to create the ambience of a fireplace with no air exchange, no emissions and no wood consumption. Of course, electricity is often generated by coal-burning plants, so the environmental issues have been pushed back in the production line.
Woodstoves that include internal baffles and catalytic burners are more energy efficient and produce less smoke than traditional woodstoves. EPA-certified woodstoves are 30% more efficient than older models. These improvements in the burn efficiency also reduce the creosote buildup on the flue pipe, which can catch fire.
Wood-pellet stoves burn cleanly and heat efficiently using pellets that are made from sawdust, wood chips, crop waste and other recycled products. Pellet stoves do require electricity to run the fan, controls and pellet feeder.
Masonry stoves generate much more heat than conventional woodstoves by circulating the hot exhaust gases though a flue that snakes through the brick, stone, adobe or cement-block stove body. The masonry mass continues to radiate heat for six to 24 hours.
Fireplace inserts are fitted inside existing fireplaces to convert them to woodstoves, which increases their heat retention. Fireplace inserts that burn gas or pellets are more efficient and burn cleanly.
Article is reprinted courtesy of The New Southwest (formerly The Tucson Green Times)