CARBONDALE — One of the more unusual applications in renewable energy could find its way to a dog-friendly park here.
Laurie Guevara-Stone of Carbondale-based Solar Energy International recently approached Carbondale’s parks and recreation commission about installing a gas lamp in one of the city’s two dog parks that would be fueled by methane from dog waste.
If the project proves feasible — and if grant funding can be obtained — it would serve as yet another renewable-energy demonstration project in green-savvy Carbondale.
Bio-methane technology isn’t new, Guevara-Stone said. “There are bio-digesters all over the world that turn waste products . . . into usable methane gas,” she said.
But this application is a little different. The project would be modeled after the Park Spark Project, which began at a dog park in Cambridge, Mass. Park Spark has grown to include similar demo projects across the country, including one in the works in Denver.
Park Spark installs a methane digester in public parks to collect dog waste and transform it into methane, according to the project website, at parksparkproject.com.
In Cambridge, the methane is used to light a small gas lamp in the park, which burns all the time.
The methane collection system involves a pair of chambers or tanks, which can be installed either above or below ground, according to a description provided on the website.
Dog owners pick up their dog’s waste using biodegradable bags and drop it into a “feeding tube” that goes to the first chamber.
The first tank is designed to be anaerobic, meaning without oxygen. The waste collects in the tank, which is filled to a certain level with water. There’s a hand crank on the outside to stir the mixture and release the methane gas, which then rises to the top of the tank.
The second chamber is an overflow tank for the liquid and keeps the digester tank at a constant level so that there’s room for the gas to collect. A pipe extends from the digester tank, bringing the methane to the lamppost, where it is burned.
“We need to do some research to see how feasible it would be to do here, and then apply for some grants,” Guevara-Stone said. “But I think it would be a really cool thing for Carbondale to have.”
In addition to its demonstration value, the project would also divert dog waste from the landfill and make use of the resulting methane on site.
“All of that dog waste just goes to the landfill now, where it turns to methane anyway, and just adds to greenhouse gases,” Guevara-Stone said.
A lot depends on whether there would be enough volume of waste to make the project work in Carbondale, but she figures a small-scale demo could be done for about $5,000.
“A small demonstration project is all we’re talking about for now,” she said. “But it would be really exciting to see something like this expand. It’s a great way to deal with dog waste, and I’d like to see it catch on and be the norm.”
Carbondale Public Works Director Larry Ballenger said the parks commission was open to the idea. “We would just need to figure out the best place to put it,” he said.
Get the scoop
Read about the move to bring poo-fueled lighting to metro dog parks at Park Spark Denver on Facebook.
