Ada County landfill’s methane gas is now powering buses, trucks. See how
Facing rapid population growth, Ada County officials have been trying to find creative ways to extend the life of the county landfill.
Now, they’re cookin’ with gas.
Biogas Development, a renewable-energy company, has built a new refinement plant that captures the landfill’s natural gas, or methane. It’s a naturally occurring waste product from landfills that is typically a headache for landfills to dispose of, since environmental regulations require it to be captured and flared off, said CEO Ahren Tryon.
Biogas’s new plant, called Hidden Hollow Energy, purifies the gas coming out of the landfill and turns it into fuel for buses, trucks and other large vehicles, Tryon said. It’s still scaling up, but at full capacity, it will produce enough fuel to power 15,000 homes, he said.
“What we’re doing is taking something that could have been a problem, and we’re making real opportunity out of it,” he told the Idaho Statesman on a tour of the plant.
LFG Development, a subsidiary of the Dallas-based Biogas Development that operates and manages the Ada County project, has overseen smaller-scale methane operations at the landfill since 2018. Under a previous agreement, LFG captured only about half the landfill’s methane to sell to Idaho Power for generating electricity, while burning the remaining half, the Statesman previously reported.
The new plant works in partnership with Intermountain Gas, which built a new pipeline to bring purified methane from the plant into its distribution system. Ultimately, it makes its way to brokers that serve bus or truck companies with large fleets looking to buy renewable natural gas to achieve their sustainability goals, Tryon said. He declined to say which companies were the end users, citing confidentiality agreements with brokers.
The price per gallon of the fuel produced, too, is confidential information, Tryon said — though he shared by email that buyers “pay a premium” for the sustainability of renewable natural gas. Landfill-generated gas is considered renewable in part because it comes from organic waste, which is continuously added to a landfill.
It’s the first plant of its size in Idaho, though some smaller plants work similarly at dairy farms around the state, Tryon said. He attributes his company’s interest in the landfill to the area’s growth.
“People move into town, people equals trash,” he said.
That trash goes into the landfill, where it’s digested by naturally occurring microbes that generate methane and other gases as waste products. For Tryon, more gas means more business.
The plant was a $50 million investment that took years to build. Ada County, which contributed no tax dollars, will get about $1 million a year in royalties from the plant, according to a county news release in May. Ada County commissioners celebrated the plant as “good business” that would help to keep costs low for users of the landfill.
The plant also helps to extend the life of the landfill, which is filling up faster than planned. The landfill has been compacting its trash to take up less space, which in turns creates landfill gas more quickly.
“It’s really a symbiotic relationship,” Tryon said.
And it’s one that he hopes will continue. The company’s gas-rights agreement with the county is for 20 years, but he aims to keep operating afterward. Landfill officials have estimated that they will close the active section of the landfill, the North Ravine Cell, in about 40 years, but it will continue to produce gas beyond that time, Tryon said.
“We foresee many decades of gas production after the initial 20-year term,” he said.
