Posted: Thursday, December 06, 2012 12:00 PM
PGE must shut down all coal-fired production by 2020
By MITCH LIES
HERMISTON, Ore. -- Portland General Electric has found that several crop residues and woody fibers offer high potential for fueling its Boardman, Ore., power plant.
Wayne Lei, a research and development director at the utility, said he was encouraged recently to learn that corn stover, pea hay, poplar planer sawdust, digested fiber from cow manure and wood chips could be excellent sources of fuel for the plant.
Under an arrangement with the Oregon Public Utilities Commission, PGE must shut down all coal-fired production at its Boardman plant by 2020.
PGE wants giant cane, or Arundo donax, to be the primary replacement fuel, but also is researching other options, Lei said.
Recent tests conducted by a Washington State University researcher show several sources could provide a viable fuel source, Lei said.
The test showed the fuel sources retain a high percentage of their solids in torrefaction, a pretreatment process that converts the biomass to a fuel source.
Lei said he would have been happy if the biomass had sustained upwards of 38 percent of their solids in the conversion.
"Every one of these items is in the low 40s or higher," he said.
Several of the woody biomass products tested, including red fir wood chips, red fir bark and white fir wood pellet fuel, tested above 80 percent.
Corn stover tested above 57 percent, pea hay tested above 58 percent and wheat straw tested above 45 percent.
Lei said plans are to use giant cane as the plant's "base anchor" fuel source.
But the utility hopes to find other sources, as well. And the recent discovery is encouraging, Lei said.