'Green Cones' reduce waste, carbon footprint
Toolbox
By Mel Huff Times Argus Staff - Published: October 15, 2007
MONTPELIER – Vermonters who want to walk more lightly on the earth have a new way to shrink their footprints.
Even better, they also have a way shrink their trash hauling bills.
It's all thanks to Green Cones, aerobic food scrap digesters that reduce as much as 20 percent of the average household's waste. And they're now available in Central Vermont through Zero Waste Inc., an off-shoot of the Central Vermont Solid Waste Management District in Barre.
Green Cones take up where composters leave off: They dispose of food scraps – raw meat, fish, banana peels, moldy cottage cheese, bones, tea bags, bread, used cooking oil – the heaviest components of household waste. Anything scraped off a plate or left over from preparing food can be put into a Green Cone.
The plastic devices come in four parts: a 17-inch-deep "digestion" basket that is buried underground; two cones, one of which fits inside the other, that stand on the basket less than 28-inches above ground; and a lid to cover the lopped-off top of the cones where food scraps are added.
The design promotes air circulation between the inner and outer layers of the cone, channeling oxygen to the food scraps and supporting the decomposition process. The sun heats the top of the cone, promoting the growth of the micro-organisms in the soil that aid in decomposition. Bacteria and insects entering the sides of the basket break down food scraps into water, carbon dioxide and a small residue that remains at the bottom of the cone.
"They've created the perfect environment for all the organisms that break food down," observed Dennis Sauer, who heads up the Green Cone project. In fact, the relationship of the parts is quite precise. Sauer said the designer found that bigger cones didn't work – they didn't get air to the food scraps as effectively.
Sauer was doing organic farming in Westminster in southern Vermont before he arrived at the Central Vermont Solid Waste Management District as the organization's composter. In July the waste district created Zero Waste Inc. as a separate non-profit to promote to adoption of Green Cones, and it named Sauer to head the effort.
Sauer's enthusiasm about the cones pours out: "The trash doesn't smell any more; it's a lot lighter; it doesn't draw flies. Your trash changes quite a bit." And he notes that the 175 households that took part in the Central Vermont waste district's two-year pilot project reported that by reducing the volume of trash, the Green Cones reduced their trash bills.
Sauer notes that Green Cones are designed specifically for digesting food scraps; leaves and grass clippings should go into the compost pile. The two complement each other. "Using a Green Cone and a composter, there shouldn't be anything organic going into the trash," Sauer observed.
Zero Waste's "Only in My Back Yard" program helps people recycle all their household organic waste at home by offering plans for building compost bins and by selling Green Cones at the deeply discounted price of $60.95 per cone, tax included. (Online prices range up to $160 per cone.)
Sauer said that one cone is enough for many families. When the pilot project was started, no one was sure how they would work when the ground is frozen. (It turned out they slow down but don't stop.) The Central Vermont waste district gave every household two cones but about a third of the families needed only one. Sauer said. He advises people to buy only one unless they have a big garden or do a lot of entertaining.
The local waste district heard about the cones from a town in Nova Scotia that had adopted a zero waste policy: Every house in the town has a cone in the back yard. The district figured that it made sense in an area as rural as central Vermont to dispose of organic waste on site rather than trucking it. "When we first started the program, we were just trying to get stuff out of the landfill," Sauer said.
Then he and his colleagues began to consider the broader benefit to using Green Cones.
"It reduces greenhouse gases," Sauer said. "The food scraps in the landfill create methane, and methane is 23 times more potent than carbon dioxide, so by getting rid of the methane, for every ton of food scraps that don't go into a landfill, you're reducing the equivalent of about five tons of carbon dioxide. And you don't emit any carbon or green house gas hauling it anywhere, even to a compost facility," he added. "That's why it's "zero waste" behavior."
Sauer noted that are 16,000 owner-occupied households in the Central Vermont waste district and almost 170,000 owner-occupied single-family dwellings statewide.
"That's a significant amount of food scraps," he said. "If 10 percent of the state had (Green Cones), you'd be reducing carbon by 32,000 tons. It's a great way for people to take personal responsibility for their waste and have an immediate impact on climate change."
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