Winning Wood Stove Designs Announced

Wood Stove Decathlon aims to usher an old-fashioned heat source to new-age efficiency.

For anyone seeking respite from the chilly fall air in Washington, D.C., this week, the National Mall was a hot place to be: Twelve wood stoves were burning away as part of a fiery competition for efficient heating.

The Wood Stove Decathlon concluded Tuesday after five days of testing and judging among teams that came from around the world. The goal? "Heat more cleanly, cheaply, and renewably," said John Ackerly, organizer and president of the Alliance for Green Heat. (See related story: "Wood Stove Contest Seeks to Fire High-Tech Solutions for Smoke.")

The New Hampshire company Woodstock Soapstone snared the $25,000 first prize with its hybrid stove, which regulates combustion and includes a regulator to ensure efficient heat. It also comes with unique plates that can be personalized to a homeowner's taste. (See related quiz: "What You Don't Know About Home Heating.")

Beyond the heating element, the decathlon had a warm air of collaboration and congeniality. Woodstock Soapstone shared its prize with the two teams that competed without financial sponsorship, Walker Stoves and IntensiFire. The $10,000 second prize was shared by Wittus-Fire by Design and Travis Industries, which donated its share of the prize back to the Alliance for Green Heat.

Winners for individual categories were HWAM for innovation; Travis Industries for lowest carbon monoxide emissions and also for market appeal; IntensiFire for affordability; the University of Maryland's Mulciber for lowest particulate emissions; and Woodstock Soapstone for efficiency.

Revival of Wood Stoves

The use of wood for residential heating in the United States has increased nearly 40 percent over the past decade, according to government figures. And Europe, where wood pellet stoves are widely used, has been at the forefront of developing wood stove technology, said Ackerly and others. (See related: "High Fuel Costs Spark Increased Use of Wood for Home Heating.") Given the robust demand, proponents of wood stoves want to ensure environmental sustainability, but future economic growth as well.

Wood stoves are diverse. Materials range from traditional steel-plated fireboxes to soapstone or other natural minerals that conduct heat naturally. Combustion chamber designs vary, and air flow can be regulated with fans or drafts. Tied to the wood stove that's been in your family for generations? No need to buy a fancy new-age machine-retrofit models are abundant.

So how does a person judge what makes a wood stove the best? The answer goes beyond how hot the room gets.

European Techniques

Testing of wood stoves is not as simple as tossing a few logs into a fire chamber.

Tom Butcher of the Energy Research Division at the U.S. Department of Energy's Brookhaven National Laboratory, one of the judges for the decathlon, explained the process.

"We're measuring primarily for two things: particulate emissions and carbon monoxide emissions," Butcher said.

There's a Goldilocks point of testing as well: Temperatures are generally the highest near the beginning of burning and the lowest at the end, so testing has to occur in the middle of the process, where it's just right.

"The sampling period is just 15 minutes," Butcher said. In other words, being precise, fast, and accurate is important.

To test the output of the wood stoves, judges climbed a ladder and measured emission levels with a suitcase-like device that held analyzers specifically developed and used for the first time in the decathlon, according to Butcher. In the U.S., testing usually occurs in a lab, but in Europe, where wood stoves are much more common, field testing is the norm.

But what about the wood? As experts have pointed out, different tree species, consistencies, and moisture content of wood can affect how efficiently and cleanly it burns.

That's where the "woodmeister" comes in.

The "Woodmeister"

Ben Myren is the guy in charge of making sure "the game is fair," at least as far as the wood is concerned.

His company, Myren Consulting in Colville, Washington, is an independent laboratory accredited by the Environmental Protection Agency to certify that wood stoves comply with EPA standards.

Using a meter to gauge the moisture levels of wood, Myren makes sure the wood is sufficiently dry before splitting it into pieces. Myren said the wood used for the competition was bought in May to ensure that it was dry.

"The key is to dry your own wood," Myren said. "There's less pollution and higher efficiency if you do. The wetter the wood, the more energy is wasted."

There are still obstacles to creating the perfect wood stove, but this decathlon was a start, said Ackerly.

"The goal is to get people to be aware that this technology is efficient," Ackerly said. "We need to get wood stoves a facelift by showing there really is a high-tech future."

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