COLUMBIA — An additional generator to transform methane gas into electricity is expected to go on line at the city landfill this year, increasing the amount of renewable energy produced in Columbia.
In 2009 the city installed a bioreactor that speeds up the process that turns waste at the landfill into methane gas, which is then captured and converted into electricity.
“Garbage in a landfill generates gas for 30 years, but there’s only about 20 years of it that can actually be captured,” Richard Wieman, solid waste utility manager, said. “The bioreactor will speed that up. It takes that 20 years and probably cuts it in half, closer to a 10-year cycle so you can capture more of the gas.”
Increased methane means more generators will need to be added in order to turn the waste byproduct into electricity.
“We will send out a description of the project and interested engineers will submit their proposals,” Christian Johanningmeier, power production superintendent for the city, said. Once proposals are requested, it could take three to four months to draw up a contract, he said.
The project has a budget of $1 million.
Whether or not the plan will include a generating unit like the ones already in place will depend on the type of technology engineers propose. Johanningmeier said the new equipment could use technology such as “fuel cells, or a micro turbine” to convert the gas into electricity.
The two Jenbacher generators in operation produced 1.2 percent of Columbia’s electricity supply in 2011, according to the 2012 Renewable Energy Report Draft.
Ronnie Tennill, operation and maintenance technician supervisor at the Bioenergy Plant, said the engines run 24/7 and "produce enough electricity to power 1,500 households."
Connie Kacprowicz, utility services specialist at Columbia Water and Light, said the third generating unit is expected to increase Columbia’s electric supply from methane to about 1.8 percent. The facility was constructed to hold four generators that would be capable of producing 2.5 percent of Columbia’s electricity.