Dec 19 - McClatchy-Tribune Regional News - Kat Hughes Columbia Daily Tribune, Mo.

If one person's trash is another's treasure, then Columbia has found a way to cash in.

Yesterday, the city dedicated its $2.5 million biogas energy plant, which uses methane gas produced by garbage to supply 1.5 percent of the city's energy use per year, enough for about 1,500 homes.

"Who would have thought you leave your trash out on the curb and we return it to you as energy back to your house?" interim Water and Light Director John Glascock said.

Each year, more than 2 million tons of garbage are buried in the Columbia landfill. Rather than allow methane produced by bacteria in the waste to seep into the atmosphere, the city built a system that vents the gas from garbage through pipes. The methane is then filtered out and used to fuel two internal combustion engines that produce electricity for the city's power grid.

Michael Carolan of Sexton Energy, the company that helped install the system, said the engines are similar to those used by cars.

The two bright green engines emit carbon dioxide as a byproduct of the process. Daily, the system also uses about 40,000 gallons of liquid such as wastewater to increase by 36 percent the rate of gas produced by the decomposing organic materials in the landfill.

Guest speaker Stan Bull, executive director of strategic partnerships with the National Renewable Energy Lab, said the system is environmentally friendly not only because it produces electricity from a renewable source, but also because it limits the amount of methane released into the atmosphere.

"It's great be-cause it will produce power as long as people will continue to produce trash, and it will reduce greenhouse gas," Bull said. "Carbon dioxide is 21 times less effective a greenhouse gas as methane."

The plant was constructed and partially funded by 2006 electric bonds approved four years ago by voters to help the city meet the renewable energy standards.

At the biogas dedication, Mayor Darwin Hindman said the city is already ahead of fulfilling those standards, and by the end of 2008 the city will provide 5 percent of its electricity from renewable sources. That is the target prescribed for 2012.

"I think the crowd here shows Columbia is interested in sources of renewable energy, and I'm very proud of that," Hindman told more than 50 people in attendance.

Although the city started purchasing wind power in September from a wind farm in King City, the biogas plant is the city's first project to gather energy from a renewable source.

Once a second biogas plant is completed next year at the Jefferson City landfill, Columbia will purchase the power it produces as a third source of renewable energy.

The city hopes to expand its biogas plant in the next five to 10 years, adding two more engines and eventually providing 2.5 percent of Columbia's electricity. Because the system relies on organic waste, a bill passed by the Missouri Senate allows the city to dump yard waste into the landfill so that it will be able to complete the expansion.

Glascock said the largest benefit of the system is that it allows the city to produce its own power.

"It took a lot of vision to pass this," he said. "It's hard, it's something new, but it's the right thing to do."