LONGVIEW — Cowlitz County and the Cowlitz Public Utility District have suspended a joint project to establish an energy production system at Headquarters Landfill because they say the cost to meet state emissions requirements has risen.
The project would have used six large combustion engines to turn methane gas into electricity for the local grid. The county and the utility announced plans to break ground on the $40 million project early next year and have it operational in 2026.
PUD spokesperson Alice Dietz said the Washington State Department of Ecology requested additional, more expensive equipment during the air quality permitting process.
The state required the engines include oxidation catalysts — which limit carbon monoxide emissions from engines, much the same way catalytic converters work on cars — and siloxane scrubbing equipment to clean the gas as it comes from the landfill.
Dietz said the additions would increase the average energy production cost from around $66 per megawatt hour to $83, and could increase the annual operating and maintenance cost for the engines by up to 30%.
Dietz said the agencies told Ecology last week the requirements would cause them to suspend the project.
“The technical and financial risks began to outweigh the rewards with this additional requirement,” Dietz writes in an email. “Despite this setback, Cowlitz PUD remains committed to exploring viable and sustainable energy alternatives.”
Andrew Wineke, assistant communication director for Ecology, said any new equipment or projects submitted for air quality review have to use the best available technology. Wineke said the department’s review found the emissions equipment would be cost-effective for the tonnage of carbon monoxide and other gases they were set to eliminate.
Cowlitz PUD planned to pay roughly $20 million of the project’s cost, with the goal of recouping their investment by selling power. The rest of the project cost was to be split between Cowlitz County, federal tax credits and $5 million from the Legislature, the latter of which will remain available through June 2025.
