San Francisco to test turning dog waste into power

Norcal Waste Systems Inc., the city's garbage company, plans to test collection carts and biodegradable bags in a city-center park popular with dog walkers.

A city study found that almost 4 percent of all the garbage picked up at San Francisco homes was from animal waste destined for the city's landfill, Norcal Waste spokesman Robert Reid said. San Francisco has an estimated 120,000 dogs.

"The city asked us to start thinking about a pilot program to recycle the dog poop in order to cut back adding more waste in landfills," Reid said.

Dog feces could be scooped into a methane digester, a device that uses bugs and microorganisms to gobble up the material and emit methane, which would be trapped and burned to power a turbine to make electricity or to heat homes.

Dogs and cats in the United States produce about 10 million tonnes of waste a year, Will Brinton, an environmental scientist and owner-director of Woods End Laboratories in Maine, said.

"As much as we love them, our pets leave a lot of manure behind them in yards and on the street and that can be a major source of contamination of groundwater," Brinton said.

European cities such as Zurich, Frankfurt, Munich and Vienna are operating biomass programs to turn waste into gas, he said.

San Francisco runs an aggressive program to recycle bottles, cans, paper and other trash and now diverts two-thirds of its garbage away from landfills.

The city's goal is a 75 percent diversion by 2010 and zero new waste in landfills by 2020.