This article about the Avista biomass facility in Washington
ran this weekend in the Spokane Spokesman-Review newspaper…
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Biomass
conundrum: where to get cheap wood waste By BECKY KRAMER , 05-16-10,
the Spokesman-Review |
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KETTLE FALLS, Wash. (AP) --
Roaring furnaces unleash the energy of wood at Avista Corp.'s Kettle Falls
generating station. Chips and bark become
white-hot ash as temperatures soar to 2,500 degrees inside the massive
seven-story furnaces. The searing heat produces steam, which runs a turbine
for electricity. The plant should be a national
model for alternative energy. Using waste salvaged from sawmills and logging
operations in northeast Washington and southern British Columbia, it produces
electricity for nearly 40,000 homes. Instead, the Kettle Falls
operation is an example of a cruel irony facing the Northwest biomass
industry: Located in the timber belt of the Selkirk Mountains, the plant has
trouble getting wood fiber at prices that produce affordable electricity. "People think, 'OK,
it's the Northwest. There's lots of wood up there,' " said John Lyons,
Avista's power supply analyst. And there is. But grinding
up low-value wood and trucking it out of the mountains is expensive. On a
per-kilowatt basis, electricity from the biomass plant costs more than
electricity from Avista's dams, a coal-burning plant in Montana or the
company's gas-fired turbines in Boardman, Ore. When fuel costs climb too
high, the Kettle Falls plant shuts down. It can be idled for weeks at a time. For Avista and other
biomass advocates, it's a frustrating conundrum. As the nation searches for
alternatives to fossil fuels, the heavily timbered Northwest offers a
potentially vast energy reserve. Trees are abundant, renewable and
carbon-neutral, but the fiber isn't necessarily cheap. "The Western U.S. is biomass
rich but it's still about fuel. Can you get it in reasonable quantities and
affordable costs? That hasn't been solved yet," said David Naccarato of
McKinstry Co., a Seattle-based firm that works on biomass projects. Avista opened the Kettle
Falls plant in 1983. One of the U.S.'s oldest and largest utility-owned
biomass plants, it's a case study in the promise and pitfalls of
wood-to-energy plants. Before the plant was built,
the skies of the Inland Northwest were filled with a smoky haze from
"tepee burners." Mills burned their wood waste in cone-shaped
structures that didn't have pollution controls. When the federal government
banned tepee burners, Avista saw an opportunity to turn the wood waste into
electricity. The furnace's high heat produces a clean burn, said Ron Gray,
Kettle Falls' fuel manager. Nearly all of the plume visible above the stack
is steam. Scientists also consider
trees a "carbon-neutral" energy source. That's an added benefit in
an era of concern about climate change, Gray said. As trees grow, they take in
carbon dioxide through photosynthesis and store it. When the wood burns or
decays, the carbon is released. As new trees grow, the carbon is absorbed
again. "It's a continuous
cycle, not a net addition of carbon to the atmosphere," said Kevin
Booth, Avista's environmental compliance coordinator. But fueling the plant is a
challenge. Each hour that Kettle Falls generates electricity, the furnaces
consume 70 tons of wood waste - 60 truckloads per day. Timber industry downturns
have made the fuel harder to get. "Every time a mill shuts down, that's
a huge amount of wood waste that's no longer on the market," said
Avista's Lyons. Over the years, the company
has branched out, buying fuel from B.C. mills and working with loggers to
salvage treetops and limbs that would otherwise burn on slash piles. Most
fuel comes from within a 100-mile radius of the plant. Any farther and diesel
costs make the wood too expensive. Avista declined to disclose
how electricity produced at Kettle Falls compares cost-wise with the
company's other electrical generation. The Spokane-based utility sells
renewable energy credits from the plant to California utilities, which
offsets some of the higher cost. But the plant was idled for
2 1/2 months last year. The downtime was related to maintenance work as well
as fuel costs. Despite the challenges,
biomass holds intriguing possibilities, said Jeff King, a senior resource
analyst for the Northwest Power and Conservation Council in Portland. Sweden gets about 6.5
percent of its electricity from biomass. In the United States, biomass
accounts for less than 2 percent of the nation's electrical generation,
according to 2008 figures from the U.S. Department of Energy. "Europeans have done
this for a long time. They use every part of the forest," King said. Europeans are also used to
high energy costs, he acknowledged. In the Northwest, where hydropower is
abundant and residents pay pennies per kilowatt for electricity, "a new
biomass plant is only barely cost effective," King said. Fuel supply is also an
issue. Banks want assurances of long-term fiber availability before they
finance projects. That's difficult in the Northwest, where so much of the
forest is publicly owned. Still, King and others have
noticed a flurry of interest in woody biomass projects in recent years. Last
year, the city of Post Falls fielded two to three calls per week from private
companies interested in building a large biomass plant in North Idaho, though
"some of them may have been kicking the tires," said Mayor Clay
Larkin. The interest is driven by
the prospect of changes in U.S. policy, King said. Government subsidies and
tax credits could brighten the economics of biomass generation. So could
federal "cap and trade" legislation, which is aimed at reducing the
nation's carbon emissions. But so far, only one large
Northwest biomass project appears to be moving forward. Adage LLC, of
Maryland, has announced plans for a $250 million, 60-megawatt power plant
near Shelton, Wash. The plant would tap the Olympic Peninsula for fiber. In the meantime, the
Seattle firm McKinstry is among those finding success with small biomass
projects. Rural schools, hospitals
and prisons have cut their utility bills by installing wood-burning boilers.
The boilers heat buildings with steam. They're particularly effective when
they replace high-cost propane or oil furnaces, said Naccarato, the McKinstry
manager. Heating one building typically
requires 400 to 600 tons of wood waste annually. In Enterprise, Ore.,
thinning 60 acres of trees each year provides enough fiber to heat a
400-student school, said Chad Davis of Sustainable Northwest in Portland,
which works on rural economic development. Idaho's Shoshone County is
one of the rural areas interested in biomass, said Vince Rinaldi, a county
commissioner. It's been a century since
1910, when one of the nation's largest wildfires burned more than 3 million
acres in Idaho, Montana and Washington. Some of the trees that grew up after
the fire are overcrowded and diseased. Rinaldi said thinning projects could
help protect towns in Shoshone County from wildfires while providing fuel for
a biomass plant. The county's put together a
working group to identify opportunities. A small electrical plant is one of
the ideas. The working group has representatives from business as well as
environmental interests, including the Lands Council of Spokane. Taking too
much fiber out of the forest raises concerns about soil productivity, said
Mike Petersen, the council's director. Decaying wood plays a role in the
ecosystem. "You need adequate
safeguards so you're protecting the ecological process," he said.
"But I think in these rural communities, something on a small scale is
possible." Small scale is exactly what
Shoshone County is thinking, according to Rinaldi. "This biomass stuff
needs to be right-sized," he said. |
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Kevin Weeks
Public Information Officer
Oregon Department of Forestry
(503) 945-7427