Burning Issue

As wood stoves gain popularity, air-quality concerns rise

The soaring prices of heating oil and natural gas are prompting many Americans to warm their houses with a less expensive fuel -- wood.

Consider Julia and Jim Fusari of Freeport, Maine. Last year, they burned 500 gallons of oil to heat their 2,000-square-foot home. They hope to cut that figure in half by supplementing their oil furnace with a new stove that burns pellets of compressed wood waste. Relying solely on oil is "just too expensive," Ms. Fusari says. "We can't afford it.".

But increased reliance on wood stoves is worrying many environmental regulators and activists, who say the practice emits harmful pollutants. Around the country, local environmental regulators are limiting the use of stoves when pollution is especially bad, and in some cases they're offering incentives to get people to buy the cleanest models possible.

"People conceive of burning wood as being natural. Tobacco is natural, too -- until it burns," says Julie Mellum, president of Take Back the Air, an organization concerned with neighborhood air pollution, and Midwest director of Clean Air Revival, a group concerned with the medical hazards of wood-smoke exposure. "When many people are burning wood, the effect is all the more hazardous."

Burning Money

Many homeowners feel they have little choice but to switch to wood stoves. Residential heating oil, an energy source for 8.1 million U.S. households, will average $4.13 per gallon this winter, according to a projection from the Energy Information Administration, a federal agency that tracks energy statistics. The average household can expect to pay $2,524 for heating oil this season, up more than 30% from last year. And natural-gas bills will increase 19% to $1,017, the agency predicts.

The threat of high heating costs is pushing up stove sales across the country. Second-quarter shipments to dealers of pellet-burning stoves and stove-like inserts that fit inside fireplaces rose 212% over the same period last year, reports the Hearth, Patio and Barbecue Association, a trade group in Arlington, Va. Shipments of wood-burning stoves and inserts were up 54%.

Burning wood offers consumers sharply lower fuel bills. In some cases, adding a wood stove can reduce oil consumption by half or more, and the cost of fuel can be as low as about $1,380 per season for a pellet stove in a midsize house. The problem? Wood burning produces toxins such as dioxin, arsenic and formaldehyde, and emits fine particles into the air -- known as particulate matter -- that can become embedded in the lungs.

Heat Source

Particulates can aggravate respiratory conditions and lead to cardiac problems and lung disease, according to Janice E. Nolen, a policy advocate for the American Lung Association in Washington, D.C.

In 1988, an Environmental Protection Agency regulation required new stoves to keep particulate emissions below certain levels. Some states and municipalities require that all stoves sold and installed carry an "EPA certified" designation.

But some clean-air advocates say the EPA's certification standards aren't stringent enough to curb runaway pollution. Even wood stoves that are certified as "clean burning" by the EPA still emit 107 times more fine particulates than an oil-fired furnace.

Earlier this year, the Western States Air Resources Council in Seattle and Northeast States for Coordinated Air Use Management in Boston, both of which are groups of air-quality agencies, urged the EPA to tighten its certification standards with stricter particulate requirements. The EPA says it's reviewing the information it needs to revise the standards.

State by State

In the meantime, local regulators are cracking down. In July, the Bay Area Air Quality Management District in San Francisco approved its first mandatory controls on indoor residential wood burning. The air district can prohibit burning on nights when particulate matter exceeds 35 micrograms per cubic meter -- something that occurred seven times during the 2007-08 winter season. Violators could incur fines of up to $1,000.

Similar measures are in effect elsewhere in California, including Sacramento and the San Joaquin Valley, as well as in other states. The Puget Sound Clean Air Agency in Seattle bans indoor burning of any type of wood or pellet stove -- unless it's the only adequate heat source -- when pollution reaches its highest levels. (That's on top of Washington State's stringent emissions standards for wood stoves, which are tougher than the EPA's.) In Colorado, residents can use only stoves certified by the EPA or state when pollution is high in the wintertime.

Other states are trying to get residents to replace older stoves with cleaner-burning models or other heating sources. The state of Washington this summer awarded $1.5 million in grants to local clean-air agencies for one such effort. Last year, a Puget Sound Clean Air Agency program offered consumers in three communities incentives ranging from $200 to $750 to make the switch. A total of 238 households participated, and more than 100 switched to cleaner-burning wood or pellet stoves.

A similar program in Libby, Mont., saw 1,130 stoves replaced between 2005 and 2007. The result: a 28% reduction in fine particulates during winter months, according to the Hearth, Patio and Barbecue Association. But Montana air officials say the state needs three years of data in order to be more certain of the program's effects.

Some states with a wealth of forestry resources are trying to balance their convenient fuel source with cleaner air. In Maine, for instance, Gov. John Baldacci has established a Wood to Energy Task Force to explore a transition to cleaner-burning stoves and pellet fuels.
What to Look For

So, what's the best move for consumers interested in heating cleanly with wood? First, do your homework. Standards vary among states and local jurisdictions, so make sure you know what's legal for your area. And look carefully at performance levels, which can vary even among certified stoves.

Hearth Condition

* The Popular Alternative: As oil and gas prices soar, people are flocking to stoves to help heat their homes.
* The Drawback: Burning wood releases harmful pollutants -- leading lots of states to crack down on wood-burning stoves.
* The Smart Solution: Before you buy, do your homework on local rules and figure out what size stove you need. Also, look into ways to keep the heat in your house, such as an efficient shower enclosure, to prevent drafts.

"Look at the emissions numbers and try to purchase the cleanest-burning unit you can," says Lisa Rector, a senior policy analyst with the Northeast States air-quality group.

EPA-certified stoves carry a label that that shows how a particular stove performs on a scale of acceptable emissions and its wood-burning efficiency. The lowest particulate emissions among stoves are generally between 1.8 and 3.0 grams per hour; the EPA limit for wood stoves with the most popular type of combustion system is 7.5 grams per hour.

Also bear in mind that some wood stoves and fireplaces are exempt from the EPA standards, which apply mainly to appliances not intended for residential heating, such as cook stoves, decorative fireplaces and outdoor wood-fired boilers. But it's illegal to install noncertified stoves in places with strict standards, such as Washington State.

Adding to the confusion, many pellet stoves don't require EPA certification at all if they already meet certain standards required for certified wood stoves. They are also relatively clean because the pellets burn more efficiently than regular wood, producing more heat and less pollution (generally about 1.2 grams of particulate emissions per hour). Stoves that burn coal, corn and other organic waste are also unregulated.

It's also important to work with a reputable dealer who can help you choose a properly sized stove. If it's too big, for example, it will overheat the room unless you reduce the air flow -- which causes a low, smoldering fire and excessive smoke. What's more, wood selection can play an important role in pollution reduction. Burning dry, seasoned wood reduces smoke output.

Ultimately, says Ms. Rector of the clean-air group, the burden falls on consumers to do research prior to purchasing a stove. "You can burn wood," she says. "But you have to find out how to do it right."

By: Suzanne Barlyn
Wall Street Journal; September 15, 2008