New systems reduce soot and smoke
Feb. 19, 2009
By Greg Elias
Williston resident Mike Isham has found the Holy Grail in a state where six-month winters and three-figure heating bills are the norm: A way to reduce his fuel bill to nearly zero.
Observer photo by Greg Elias
Veronica Jordan, accompanied by her 18-month-old grand-nephew, Iverson, stands next to her wood-fired boiler. She enjoys cranking up the thermostat without worrying about it hiking her monthly fuel bill.
Observer photo by Greg Elias
Mike Isham shows off his wood-fired boiler. Isham harvests wood from his own land to fuel the new heating system.
Observer photo by Greg Elias
This insulated tank in Isham’s basement holds 1,500 gallons of water heated by the wood-fired boiler and functions as an energy storage system, supplying heat and hot water even after the fire has burned out.
The secret sits in a barn behind his home on Oak Hill Road. Inside, an aquamarine-colored box the shape and size of a refrigerator burns wood, putting out enough BTUs to heat his family’s sprawling farmhouse.
Isham’s wood gasification heating system is a new twist on mankind’s oldest energy source. With the help of a complex system of fans, thermostats and plumbing, it burns wood far more efficiently and cleanly than an old-fashioned stove or fireplace.
Linked to a water tank the size of a small swimming pool, Isham’s system replaces an oil-burning setup that included three boilers and five hot water heaters. Isham needs to fire the new boiler up just twice a day in the winter and about once a week in the summer, when it’s used only to supply hot water.
“It’s a pretty smart system,” he said. “It’s not like the old wood stoves, where the fire goes out and the house gets cold.”
With many people struggling to pay rising heating bills and increasing concern about the environment, alternative heating systems are a common topic these days.
Wood is a popular option. Many Vermonters have long used wood stoves to supplement oil or gas furnaces. Now, some like Isham have shifted entirely to the fuel source.
Isham calls his American-made Econoburn boiler the “Cadillac” of wood-fired systems. He admits the $50,000 price tag isn’t for everyone.
The cost included heavy-duty plumbing and connections to keep his old oil burner working as a backup. It is big enough to heat the farmhouse, built in 1852, and its attached apartments.
Isham said he could have opted for a smaller, less expensive system, but he likes the fact that the furnace is large enough so he only has to load wood infrequently.
Williston resident Veronica Jordan also has a wood gasification system. Her 2,400-square-foot home in the village was built in the early 1800s. Her system is considerably smaller than Isham’s, but puts out enough heat to keep her abode a toasty 72 degrees.
Jordan paid roughly $16,000 for the system, which included the boiler, plumbing and installation costs.
“It definitely was a chunk of money,” she said. “But I think in the long run it will basically pay for itself.”
Jordan noted with satisfaction that she used to pay $3,200 for natural gas to heat her home each year. Now she spends a fraction of that for wood, supplied at a reduced price by a son who works in the timber business.
Scott Gardner is president of Building Energy, a Williston-based company that conducts energy audits and installs alternative heating and energy systems.
He said wood gasification systems are best suited to large, older homes, and they work well for people who have lots of wooded land.
“It’s a good choice to economize for those who have their own wood or have a larger structure that is difficult to insulate efficiently,” Gardner said.
Green and clean energy
Wood gasification systems differ from fireplaces and older wood-fired stoves in that they produce little of the polluting black smoke associated with those devices and burn wood much more efficiently. Isham said he sees only a little white smoke when he first stokes his boiler.
Wood gasification burns cleaner by forcing a mixture of fresh air and hot smoke back down through the fire. The process raises the temperature within the boiler, producing temperatures reaching 1,800 degrees and burning almost all the excess gas that would have otherwise gone into the atmosphere.
The systems work at thermal efficiencies of around 90 percent. Older wood furnaces and stoves work at only about 50 percent efficiency.
In Isham and Jordan’s systems, the boiler heats water stored in insulated tanks that circulates to baseboards throughout their homes.
Burning wood makes particular sense in Vermont, where there is a large enough supply of timber to heat every home in the state, Gardner said. When harvested responsibly, wood is a renewable resource.
Wood sold for fuel is usually taken from felled timber, Gardner said, and clearing deadwood actually helps maintain healthy forests.
Experts generally view burning wood as carbon neutral because decaying trees left to rot in the forest also emit carbon, although that equation may change for older, less efficient wood stoves or fireplaces.
Newer wood stoves certified by the Environmental Protection Agency also operate cleanly and efficiently. Pellet stoves in particular are a good alternative for many homes, Gardner said.
Wood now an expensive fuel
Burning wood can reduce heating bills, but the fuel is not free unless you owns lots of land like Isham and are willing to put your own back-bending labor into cutting, splitting and stacking it. Isham calls his woodpile — 4 feet high and 50 feet long — his “wall of toil.”
Cord wood costs vary depending on demand and other factors. Kiln-dried, split wood has been selling for around $300 a cord this season. Green wood goes for about $200 a cord. Those prices are unusually high, said Gardner, who anticipates costs will fall with new suppliers set to come online.
Jordan estimated she will use 10 cords this year. If she bought dried wood on the open market, it would cost her almost as much as she was paying for natural gas heat.
But gas and oil prices are likely to rise again. If wood costs drop, wood-burning systems will be a more economical choice compared to other fuel sources.
Isham said when the price of oil inevitably spikes again, he will be happy he invested in wood heat.
“When heating oil gets back to $4.50 a gallon and propane is expensive too, I’ll be grateful I’m not paying for that,” Isham said.