Progress on biomass: Finally seeing the results of waste-to-energy
By Allen Best
Posted: 02/01/2014 05:00:00 PM MST
In Gypsum, located 140 miles west of Denver, a biomass mill began operations in December, burning wood to create 10 megawatts of round-the-clock electricity. A wall board plant is at left, the biomass plant is to the right. Bill Heicher photo. (The Denver Post | Bill Heicher)
For most of the last decade, Coloradans have been talking about how to make good use of their mountain forests, dying and gray. Something is finally happening.
In Gypsum, 140 miles west of Denver, a biomass mill began operations in December, burning wood to create 10 megawatts of round-the-clock electricity.
In Colorado Springs, the city utility began mixing biomass with coal in January to produce 4.5 megawatts of power.
In Pagosa Springs, a 5-megawatt biomass plant may be launched next year, producing one-sixth of the baseload demand in Archuleta County.
And at Xcel Energy's headquarters in Denver, environmental officials are sorting through proposals for a 2-megawatt biomass demonstration plant. The utility wants to understand the technology, the problems and promises.
This isn't much electricity compared to the 1,426 megawatts generated by the Comanche coal-fired complex at Pueblo and the 1,139 megawatts at Craig. But biomass plants can and should be part of the electrical mix. In providing a market for woody material, they can make forests less vulnerable to fires like the ones that have killed nine people and destroyed 1,164 homes along the Front Range over the last two years.
Biomass also displaces burning of fossil fuels, reducing emissions of carbon dioxide, a greenhouse gas. That's worth something, maybe a lot to Glenwood Springs-based Holy Cross Energy, which is paying extra for the electricity produced at Gypsum to help reduce its carbon footprint. It expects to be at 23 percent renewables later this year.
Colorado environmental groups, however, are skeptical that biomass plants will actually lower carbon dioxide emissions. "We're saying we want to see the analysis of greenhouse gas impacts," says Gwen Farnsworth of Western Resource Advocates.
Biomass clearly can reduce greenhouse gas emissions by displacing fossil fuels, says Keith Paustian, a professor of soil ecology at Colorado State University. "There are questions as to what degree you do that, and obviously, you want as low a carbon footprint as possible," he says.
Paustian hopes a more detailed accounting of carbon impacts will be a byproduct of the $10 million research project he is leading. The project, the Bioenergy Alliance Network of the Rockies, seeks to examine the potential for conversion of the 22 million acres of beetle-impacted wood in the Rocky Mountains into bioenergy.
An even broader fear among some environmental groups is that public lands will be managed to feed the hunger of biomass plants, instead of the bieomass plants being a useful tool for curbing fire risk. "We don't want the tail wagging the dog," says Sloan Shoemaker, director of the Carbondale-based Wilderness Workshop.
If Eagle Valley Clean Energy, developer of the plant at Gypsum, sticks to its projections, that won't be a problem. It insists that at least 30 percent of wood will come from landfills, another 20 percent or more from private lands, and a minimum of 40 percent from state or federal lands.
The plant is designed to operate for 30 to 40 years, long after forests now gray have become green once again.
Stewardship contracts are one mechanism for delivering wood from federal lands to biomass plants. Authorized by Congress in 1998 as an alternative to timber sales, they allow for a more nuanced management of national forests than timber sales allowed.
For example, a stewardship contract across the White River National Forest calls for the agency to pay a contractor, Western Range Resources, $1,500 per acre for 1,000 acres per year for wood removal. Much of that wood will end up at the biomass plant in Gypsum.
Through this program, the Forest Service hopes to also get aspen forests on the periphery of the Flat Tops cut, to allow for more wildlife habitat but also to reduce wildfire threat in Summit County, near Breckenridge and also near Green Mountain Reservoir.
"There's a lot of doghair in Summit County," says Jan Cutler, silviculturist on the White River National Forest, referring to dense forests of small trees. "And a lot of standing and falling dead trees are rotted out at this point. They have no merchantable value as far as saw timbers."
The partnership between Denver Water and the Forest Service is another model for reducing fire risk while producing wood for biomass plants. In that partnership, each agency chipped in $16.5 million to address dead and falling trees on 6,000 acres upstream of Dillon Reservoir, one of metro Denver's primary water sources.
Cutler says fuels removal for biomass and other purposes altogether will probably occur on just 10 percent of the 2.2 million acres of the White River National Forest, which extends from Breckenridge to Meeker and Carbondale.
Fire risk is not totally eliminated. The right combination of climatic conditions in the higher, subalpine forests will someday yield a fire comparable to the one that burned 1.2 million acres in and near Yellowstone National Park in 1988, says Tony Cheng, director of the Colorado Forest Restoration Institute.
But land managers do hope to provide firefighters safe zones from which to fight major fires. Taking the slash piles after thinning operations or removing the debris to produce slash creates an added benefit, says Cheng.
At Pagosa Springs, fire was frequent prior to about 1900. Growing seasons there are longer, the climate more moist, and soils rich, all of this conspiring to produce bounteous forests of ponderosa pine and now, because of fire suppression, white fir. Houses now sprinkle the private lands along and sometimes on in-holdings within the national forest, a combustible mix.
In creating the stewardship contract on the San Juan National Forest, foresters identified forest types within a 50-mile radius of Pagosa they wanted treated, then stripped out wilderness and roadless areas. That left 140,000 acres for the stewardship contract.
The buyer, local entrepreneur J.R. Ford, can harvest wood from 1,500 acres per year. He is required to pay the U.S. government for trees greater than 10 inches in diameter. He will mill these logs at a sawmill beginning in April, shipping the blocks of wood to a sawmill elsewhere for refined sawing. For trees of less than 10 inches in diameter, the government will pay Ford. He can leave no slash piles of trimmings behind.
In addition, Ford will draw upon another 300 to 400 acres of private land. This will provide 50,000 tons of wood chips for the biomass plant he hopes will go online next year.
Steve Hartvigsen, supervisory forester for the Pagosa Ranger District, says the stewardship contract will yield no permanent roads. "That may mean temporary timbering roads, but they must be rehabbed," he says of the rehabilitation process.
The San Juan Citizens Alliance, a grassroots environmental group, has endorsed Ford's biomass plans. "That scaling is what made us comfortable. It wasn't a 20-megawatt deal," says Jimbo Buickerood, the group's public lands coordinator. That smaller plant results in shorter distances for trucks to haul wood. Experts say biomass must commonly draw wood from within 50 miles, to contain deal-killing truck-hauling costs.
Whether Ford goes ahead with the biomass plant depends partly upon how much Durango-based La Plata Electric will pay for the electricity. Ford says he needs 15 to 20 percent more than what the La Plata and other electrical cooperatives pay wholesale provider Tri-State Generation and Transmission.
"The coops are paying between 7 and 7.5 cents per kilowatt and are selling it for 11 or 12 cents, depending upon the area," Ford says.
In Europe, biomass production is far more common than in the United States. There's a good reason: Europe has fewer fossil fuels at its disposal. All electricity is more expensive, generally 14 to 18 cents per kilowatt.
All biomass plants in Colorado contemplate subsidies. The Gypsum biomass plant got a $250,000 biomass utilization grant from the U.S. Department of Agriculture. Plus, it enjoys $40 million in loan guarantees from the Rural Utilities Service, the same agency that financed many of the co-ops coal-fired power plants.
Xcel also expects electricity from biomass will cost more, and is seeking approval from the state's Public Utilities Commission to pass along higher costs to customers. The utility is seeking plants that use gasifier technology, as is planned at Pagosa Springs, instead of the boiler technology now in place at Gypsum. It has fewer emissions and uses no water. That, says Kathryn Valdez, manager of environmental policy for Xcel, is an important consideration if plants are to be located in places that will minimize haul distances.
Xcel specifies just a 2-megawatt plant for its 10-year demonstration plant.
Phil Kastelic, of Colorado Forest and Energy, a company proposing to build a demonstration plant in Gilpin County, says that size matters. "There just aren't that many places where you can put five-megawatt of generation and have local feedstock to support it."
In other words, biomass plants aren't the answer to everything that ails us. They won't immediately turn our forests green, nor will they alone replace the fossil-fuel plants that are fouling the atmosphere with greenhouse gases.
But biomass has another attribute. Think of it as the energy equivalent of community agriculture. The 20th century was all about bigger and more centralized production of everything. This creates huge supply lines, mile-long coal trains going to plants, and high-voltage power lines leaving them.
It's easy to think of water originating in the tap, electricity in the outlet, without broader consequences. Smaller sources of power generation, close to their locations of use, keep us in touch with the spider's web of our relationship to the energy we use.