BEND — Deschutes County could soon start harnessing the gaseous byproduct of decomposing waste in Knott Landfill to create “biogas” that can be used to help power the local energy grid.

Between 45% and 60% of landfill gas is made up of methane, which is constantly being vented from Knott Landfill. Currently, that methane is not put to any use. Instead, it’s burned off, which emits harmful carbon dioxide into the air. Deschutes County wants to change that.

“We’re going to take the landfill gas, run it through a process to clean it and then that methane would be distributed into the local gas distribution network,” said Chad Centola, director of the county’s solid waste department.

Centola is awaiting a contract with Cascade Natural Gas, which could likely contribute millions of dollars in equipment and expertise to transform Knott’s methane into a source of natural gas for Deschutes County residents.

“Harnessing the landfill gas and using it as a renewable energy resource is generally a great option,” said Heather Kuoppamaki, a senior air quality engineer with the department.

Knott Landfill takes in about 650 tons of waste per day, Centola said.

“We’re going to reach capacity in 2029. There will be marketable amounts of methane coming out of the landfill for years to follow that,” Centola said.

The county attempted a similar project to harness methane gas nearly a decade ago.

In 2011, the county began negotiations for a methane gas conversion project that was planned with a 2018 start date. Deschutes County awarded a contract to the California-based Waste to Energy Group.

In the years following, the group repeatedly missed deadlines due to funding woes, according to The Bulletin’s archives. The contract between the two was terminated in 2016.

With the county’s currently proposed project, Centola said Cascade Natural Gas could likely capture 2,000 cubic feet of gas per minute. The average residence in Deschutes County uses more than 75,000 cubic feet of gas per year, according to a 2020 report from the Oregon Department of Energy.

Around 25% of Knott Landfill’s contents is food waste, according to Udara Abeysekera Bickett, the program manager for The Environmental Center’s Rethink Waste Project. The center is an education program encouraging waste reduction and prevention.

“A lot of people think food just breaks down in a landfill, but landfills are actually designed to not allow things to break down very well into the environment,” Bickett said.

In part, that’s a good thing, because it keeps harmful substances out of soil and water, Bickett said.

“When food’s not breaking down in a landfill, it’s turning into this mush that’s producing methane. That’s where we see the connection between food waste and methane production,” Bickett said.

Diverting food waste from the landfill to compost or to feed livestock not only reduces solid waste within a landfill, but it can also reduce methane emissions from those landfills, she said.

“There’s a limited scale of how much gas can be produced from this,” Neil Baunsgard, the transportation and climate advocacy manager for The Environmental Center.

He said there is a propensity for making a false equivalency that more natural gas might mean Deschutes County residents and businesses can use as much natural gas as they want. That is not the case.

Around 38% of households in Deschutes County use natural gas for heat, according to data from the Oregon Department of Energy.