Skip to main contentAs Portland General Electric fights an early closure of the state's only coal-fired generating plant, a local entrepreneur has stepped forward with what he and the utility hope is a solution.
Environmental groups want PGE to close its Eastern Oregon plant in Boardman by 2014 because it's a major polluter; the state's largest utility hopes to delay closure until 2020. Oregon's Department of Environmental Quality has ordered PGE to install pollution control equipment to keep the plant open beyond 2014.
Into that battle steps Hiroshi Morihara, an engineer with a background in chip fabrication and biotech.
Working with a team of chemists and engineers at the Gresham startup HM3 Energy, Morihara says he has fine-tuned a process for torrefaction, which turns biomass—the byproduct of materials such as timber harvest slash—into briquets that can be burned like coal but much more cleanly.
Jaisen Mody, who runs PGE's generation products group, says the utility is working with Morihara and is intrigued by biomass.
"The advantage is, you may not need to change any of the plant's generating components," Mody says. "We definitely think it is a viable process, but there are a lot of questions we have to answer."
Torrefied biomass is dried in the absence of oxygen, and creates about 20 percent more energy per ton than coal. PGE's Boardman plant burns about 2 million tons of coal annually and would need about 1.6 million tons of torrefied material to replace that volume.
The Sierra Club, which has pushed hard for Boardman's closure, is skeptical that biomass is the answer. "We'd like to see them close Boardman and pursue more proven alternatives," says Cesia Kearns of the Oregon Sierra Club.
Ray Wilkeson, director of the Oregon Forest Industries Council, says the primary market for biomass today is a "hog fuel" created by burning unprocessed biomass in kilns used to dry wood. Hog fuel furnaces face increasing regulation in the future, however. And the forest council is interested in finding alternative uses for their businesses' byproducts.
"We would welcome the opportunity to expand our markets," Wilkeson says. "And both gubernatorial candidates have talked about biomass as an opportunity for rural Oregon."
But to make that promise a reality, Morihara must answer two major questions: whether torrefied biomass works on the massive scale Boardman would require, and whether the price can compete with that of other fuels.
Earlier this year, HM3 and PGE jointly paid for experimental burns of a mixture of 90 percent coal and 10 percent torrefied briquets. Mody called the results promising, but needs to know more about the emissions a stream of 100 percent torrefied material would produce and whether it would gum up Boardman's burners.
PGE researchers are also looking at the possibility of creating a biomass source by farming a type of giant reed that grows a foot a week.
"We think we would need 100,000 acres," Mody says. "The good news is, in this part of Oregon there is more than enough land, with plenty of sunshine with water rights available."
Growing some or all of the material nearby would address the other big obstacle: cost. PGE pays about $30 a ton for coal, a price the utility expects will double under future carbon regulation.
Today, Morihara thinks torrefied material would cost $120 per ton before accounting for state and federal tax credits that have powered the growth of wind farms. He expects large-scale production would reduce the price.
That's still a long way off, and Mody says no utility is much further along than PGE, although Canada's Ontario Power hopes to convert a couple of its Boardman-sized plants to biomass.
"Nobody's there yet, but I think the world's moving to biomass in a big way," Mody says. "The ultimate solution is to replace 100 percent of the coal with 100 percent biomass, but it's going to take time, and that's why we're hoping to keep Boardman open until 2020."
Morihara's company figures that Oregon produces 4.8 million of the 8.6 million dry tons of biomass produced annually. The largest source, 2.3 million to 4.0 million tons, consists of timber harvest slash—wood debris left over from logging.
WWeek 2015