Landfill gas electricity project set to launch this summer
By Ben Moger-Williams
If you haven’t read “Gas Cyclones and Swirl Tubes,” you are probably not alone.
But to Ed DeVarney, who is getting ready to fire up a small scale electrical generation project in Williston using landfill gas, it is practically gospel.
“Anytime you talk to anyone in a particular discipline, you better keep your ears open,” DeVarney said in an interview at the Williston landfill last week. “Because that’s your magic moment to make up what you didn’t learn in engineering school.”
For the last five years, DeVarney, 53, has traveled – anywhere from 4-12 times a week – from his home in Milton to the site of the closed Phase III landfill in Williston owned by the Chittenden Solid Waste District to work on his project. DeVarney said the generators should be online this summer.
Beneath the lush green hill that is Phase III’s outer facade lies a quarter-million tons of decomposing trash. The landfill was closed in 1995 and has since been generating a mix of methane, carbon dioxide and other organic compounds, produced by microbes eating the garbage. For more than a decade, the gas has been burned off using flares, rated to destroy 98 percent of the greenhouse gases. DeVarney’s idea is to capture the gas and reroute it into engines, which, when operational, will produce 0.09 megawatts of electricity for at least five years. The electricity will be fed back into the electrical grid and sold to Green Mountain Power.
DeVarney, a retired auto mechanic, has a do-it-yourself philosophy about his project. He hopes to prove that a small-scale electricity generation project – using any renewable energy source – is both profitable and affordable.
He keeps the cost low by refurbishing used items purchased at online auctions, using recycled materials when possible, and by doing virtually all of the work on the project himself.
“This whole project has been: What can I buy on eBay, what can I use for off-the-counter stuff?” he said.
DeVarney estimates that by acting as his own engineer, legal team and construction crew, he has saved at least 50 percent over a typical landfill gas electricity generation project.
So far he has constructed a building to house the generators; bought the generators themselves (purchased on an Internet auction); designed the fuel delivery and engine control system for the generators; installed a backup flare to burn off excess gas or operate in an emergency shut down; and built a cyclonic moisture separator based on designs in “Gas Cyclones and Swirl Tubes,” by Alex Hoffman and Louis Stein. The device is used to separate water from the landfill gas as it comes out of the landfill, before it goes into the generators.
“The gas is allowed to enter, but centrifugal force says to the water vapor, ‘you can’t hang on any more, honey,’” he explained.
His use of the book is indicative of the types of things he’s had to learn – without the benefit of a college degree.
“I’m an avid reader and student of all things fascinating,” he said. “I have no institutionalized post-secondary education whatsoever.”
DeVarney ordered the book online, read it, but still had some questions about how to make the moisture separator. So he e-mailed one of the authors, Louis Stein, and eventually called him to ask for advice.
“In the ensuing week, I give him my rudimentary drawings, he marks them up, sends them back, and all of a sudden I have a cyclonic collector supposedly of my design, but validated by ‘the man,’” DeVarney said. “That’s the kind of help that I’ve gotten.”
Vermont has three operational landfill biogas electricity-generating projects, according to a report in “The Vermont Energy Digest,” published by the Vermont Council on Rural Development. A landfill in Brattleboro produces about 0.25 MW; the Intervale in Burlington produces about 0.7 MW; and the Coventry landfill cranks out 6.4 MW. The CSWD has been planning a regional landfill in Williston since the 1990s. If the landfill is built, it could have a capacity of 1 MW by 2015, according to the report. DeVarney’s 0.09 MW is comparatively tiny, but he estimates that is still enough electricity to power 75-80 homes.
Green Mountain Power will pay DeVarney by the kilowatt-hour, a portion of which will go to CSWD. The price is calculated hourly by ISO New England, a nonprofit company that oversees the region’s electricity market. DeVarney said he has personally pumped over $100,000 into the endeavor, but he hopes to have the project pay for itself within two years of coming online.
Dave Lamont, power planner for the state Department of Public Service, said projects like DeVarney’s, while small-scale, are a positive thing.
“This is not going to solve the world’s energy problems,” Lamont said. “But they do add up to something. Taken on an individual basis we’re creating energy from waste, which is good.”
According to the federal Environmental Protection Agency’s Landfill Methane Outreach Program, the environmental benefit of DeVarney’s generation project (compared to using fossil fuels to generate the same capacity) is equal to planting 128 acres of forest or taking 90 vehicles off the road.
After the Williston project is live, DeVarney hopes to expand. He sees this as just the beginning of a series of waste-to-energy projects.
“I want to look at what you’re throwing away, where I can park, is there electricity to it, and I want to make a project,” he said. “And I don’t care if it’s a third this size. But I do want to make 200 of them.”