Every time you poop in Portland, you're helping the environment

Photo: David Gn Photography/Getty Images Portland's plan to convert solid human waste into a renewable...

Portland may soon become the nation's leader in converting bowel movements into a force for good.

The city, which already turns about three-quarters of the gas produced by raw sewage into electricity and heat, is going to build a $9 million plant to convert the remaining quarter into natural gas, the Oregonian reported Thursday. The natural gas will be sold through a Portland-based distributer to governments and organizations looking to replace diesel fuel-powered vehicle fleets.

"We're going to be turning poop into power," Commissioner Nick Fish told the Oregonian.

Currently, 77 percent of city sewer system's methane is used to generate energy at the Columbia Boulevard Wastewater Treatment Plant. The remaining 23 percent is burned, resulting in carbon dioxide emissions.

The new treatment facility, to be built at the existing wastewater plant, will convert the leftover methane into natural gas, a renewable energy source. Natural gas has increasingly been used to as a substitute for diesel fuel.

The city expects to make from $3 million to $10 million a year from the gas production, not a bad return on its $9 million plant investment.

And its air will be cleaner, naturally.