Oregon's last coal plant evaluating biomass

By Anna Austin | March 11, 2011

Portland General Electric, the last coal-fired power plant in Oregon, is evaluating arundo donax as a potential biomass fuel.

New rules adopted by the state last year require the plant to cease burning coal or close down by the end of 2020, said PGE spokesman Steve Corson. “Conversion is an option we’re looking at, and biomass is attractive for a number of reasons but there are still a number of unanswered questions.”

Corson said PGE has been looking at arundo donax, otherwise known as giant reed, and other potential biomass fuel options for quite awhile. “Giant reed is the focus of our investigation at this point,” he said. “It all boils down to the productivity of the plant. It can grow 20 feet in a year and produce a huge amount of material, which is what we’d need with a 585-megawatt power plant, even if we didn’t run it at the full load.”  

PGE has partnered with the Hermiston Agricultural Research and Extension Center to conduct planting trials, which are currently underway and will eventually total about 15 acres. The groups plan to watch how the plant grows in the region—whether it can survive the winter and how it might compete with other crops—and when it has reached maturity, PGE will run test burns. Corson said that will possibly happen in late 2012 or in 2013.

Eventual plans include torrefying the biomass when it reaches the power plant. “Ultimately the concept that would make the most sense would be to grow adrundo donax in the immediate vicinity of the plant, eliminating transportation costs, and to then put it through a torrefaction process that would leave it in a form that we could pulverize and use the same way we’re using coal,” Corson said.

The test burns will allow PGE to get a better handle on how giant cane would behave in the power plant, and the emission control equipment that would be required for a commercial scale facility. “If all of that looks favorable, we will take the project through a resource planning process with our public utility commission to make the determination of whether it would be the best decision for our customers to proceed,” Corson said.