The food we eat supplies energy to our bodies, but the food we don’t eat can provide energy to our power grid.
Bannock County turns gas generated from the landfill into power through the Gas-to-Energy program and is gearing up to expand the program.
Landfill gas – composed of about 50% methane and 50% carbon dioxide – is generated when organic material, like our leftover food scraps, decomposes. Instead of the gas escaping into the air, the gas is captured, converted, and used as a renewable energy source for Idaho Power customers.
Bannock County’s Gas-to-Energy program currently generates between 1,450 to 1,500 kilowatts per hour (kWh), which is enough to power about 46 homes a day.
The gas collection system consists of wells installed into the waste mass, which are connected with piping to form a network. Blowers, commonly called compressors, create a vacuum to “suck” the gas out of the landfill and compress the gas to a higher pressure.
The gas is fed to one of Bannock County’s two Cat Industrial Engines that are attached to generators. The engines spin the generators, creating electricity to be sold to Idaho Power to be put back into the electrical grid.
“Eventually, we want to run both of our engines simultaneously so we can double the amount of kilowatts we’re generating,” said Chris Taylor, the Landfill Gas-to-Energy System Operator. “We just have to have enough gas to run the second generator at a high enough capacity to generate a profit and not cost us money to operate it.”
Since starting the Gas-to-Energy program in 2014, Bannock County has sold more than $5.7 million worth of energy to Idaho Power. The money generated from this program is put back into the landfill’s enterprise fund to be used for landfill operational costs and capital improvements.
Not only does this program help fund landfill operations, but it also promotes sustainability. Greenhouse gases, like methane and carbon dioxide, are the most significant drivers of global warming, according to the Environmental Protection Agency (EPA).
“We’re turning a negative into a positive. The EPA requires us to keep our emissions down, but our emissions aren’t even at the level they would require us to intervene. This is just a good, common-sense way to be fiscally and environmentally responsible,” Taylor said.
The EPA requires intervention to reduce greenhouse gases when Non-Methane Organic Compound (NMOC) emissions reach 50 metric tons. Bannock County is reporting an average of less than four metric tons of NMOC emissions.
Bannock County is among four counties in Idaho that operate a Gas-to-Energy program: Kootenai, Ada, and Cassia Counties.