Apr 27 - McClatchy-Tribune Regional News - Laura Snider Daily Camera, Boulder, Colo.


Boulder is progressive, many say. Boulder is green. Boulder is striving to meet the Kyoto Protocol.

And Boulder has a coal plant within its city limits.

True, the Valmont power plant is owned by Xcel Energy, and true, the electricity feeds into the grid and doesn't necessarily power homes in Boulder. But still, the three tall smokestacks on the eastern side of town have, for a growing number of residents, become a symbol of the old energy economy where fossil fuels are king.

"We need to retire Valmont, and if we can't, we need to hybridize it," said environmental geologist Alison Burchell, who helped start the recently formed Boulder Climate Action Network. "I'm working with the United Nations on programs in other states and other countries to hybridize coal plants, why not here?"

Xcel does not currently have plans to convert the Valmont plant, but they are looking at several different strategies for hybridizing power plants, including adding solar panels, said Xcel spokesman Tom Henley.

The call to shut down Valmont, one of Xcel's older coal plants, isn't new. But the interest in finding a compromise -- a way to keep the coal plant running without the coal -- is.

People within the climate action network, a group of scientists, policy experts, activists and environmentalists who are committed to helping Boulder make more drastic carbon cuts, want to see Valmont run on biomass, burning forest slash, beetle-killed trees and invasive shrubs.

"As a visible symbol of how Boulder gets electricity, Valmont provides us an opportunity to show our country and the world how to stop burning coal," reads a comment to the city council prepared earlier this month by the climate action network.

Converting coal plants to run on biomass is a growing trend in the United States, according to the U.S. Environmental Protection Agency. Plans have been made since 2006 to convert plants in Hawaii, New Hampshire and at an Xcel-owned plant in Wisconsin.

And most recently, Atlanta-based Georgia Power got approval to convert an older coal-burning plant in the southwest part of the state to a 96-megawatt biomass plant, the largest in the country.

"Plant Mitchell is an older coal-fired plant," said Lynn Wallace, spokeswoman for Georgia Power. "With the environmental regulations and the environmental controls that we're having to put on our coal plants, it was more cost-effective to just go ahead and convert it to biomass."

Plant Mitchell and Valmont are not dissimilar. They were both built in 1964, and they have similar capacities for burning coal. They are also both built in areas where there's a lot of wood being cleared from the forest.

"It's in southwest Georgia," Wallace said. "We have an abundance of surplus wood waste. ... This is leftover stuff that can't be used by for other purposes: tree tops, misshapen wood, limbs, needles and leaves."

Locally, the U.S. Forest Service, the county, the city and private land owners are all thinning the forests, trying to create a healthier ecosystem and reduce wildfire risk. Much of the excess wood is now burned in place or at slash drop-off areas. A five-county initiative based in Fort Collins called Peak to Peak Wood, which includes Boulder, is actively trying to create markets for the excess biomass, so it can be sold instead of burned.

Converting a coal plant to biomass isn't without difficulties. A ton of biomass has less energy than a ton of coal, and the coal plant has to be retrofitted to burn the wood. The overhaul on Plant Mitchell, which includes a new boiler, will cost upwards of $125 million.

Every type of fuel burned -- whether natural gas, coal, biomass or even tires -- has different properties and all the costs and benefits need to be considered, said Terence Parker, who researchers energy conversion systems at the Colorado School of Mines.

(c) 2009, McClatchy-Tribune Information Services