On December 14, 2018, Dan Tonello, Manager at the Persigo Wastewater Treatment Plant operated by the City of Grand Junction retired after almost 35 years in public service.
Dan championed a first in the Nation project by converting methane produced at the treatment plant to running vehicles on biofuel! “This lemons to lemonade approach took tremendous persistence and support, funding as an enterprise and not from taxpayers, which resulted in a great benefit to the community and environment,” said Dan the day before his retirement.
In 1982, Dan began working at the wastewater treatment facility located downstream of the City along the Colorado River. Basically, water is purified by removing solid sludge from sewage using microbes. This process generates methane, a greenhouse gas. At that time, they collected about 16% of the methane to heat the microbial digestion plant but needed to burn and flair off the remainder gas to prevent explosions.
In 2005, he promoted the idea of capturing compressed natural gas (CNG) to be a useful byproduct by considered three options: 1) operating microturbines which had a low return on investment (ROI), 2) fuel cells that were expensive and no payback, and 3) running vehicles using CNG as a biofuel. This third option could have a large financial ROI and greatly benefit the environment if they could create a market. To make the idea work, they would need to collect methane at the plant, distribute the CNG, and provide vehicles that could run on CNG. So they began with the end in mind.
Initially Dan and his supporters in 2011 created the CNG filling station at the City yard. As vehicles needed to be replaced, instead of purchasing new gasoline and diesel vehicles, they sought to purchase CNG vehicles. Over a four-year period, the City purchased 32 vehicles to operate on imported biofuel. Once demand for CNG was established, Dan acquired revenue funds of $2.8 million for the methane collection system at Persigo ($1.5 million) and 5.7 mile pipeline from the plant to the city yard ($1.3 million).
The process to capture methane at a wastewater treatment plant works in the anaerobic digester by first removing hydrogen sulfide (H2S swamp gas) with an iron oxide hydroxide metal, activated carbon to remove organics, and membrane filtration to separate out methane CH4 from the H2S. A chiller removes condensate (moisture) so the gas can be moved through the pipeline. The City purchased the system from Unison Solutions.
Clean burning CNG biofuel is available to the public, for City Grand Valley Transit, City Vehicles like trash trucks, Parks and Wildlife, and others refilling at Monument Clean Fuels.
On March 28, 2016, Dan was interviewed on National Public Radio. Here is an excerpt of the interview:
DAN TONELLO, Manager, Persigo Wastewater Treatment Plant: This is what eight million gallons of sewage a day looks like.
DAN BOYCE: Yes, human waste can also be turned into power. We’re at the wastewater treatment plant in Grand Junction, Colorado. And that distinctive smell of sewage is starting to smell like money to manager Dan Tonello. The plant has had a digester for decades, but most of the methane used to be flared off into the air.
DAN TONELLO: Not good for the environment and a waste of a wonderful resource.
DAN BOYCE: So the city spent just under $3 million for the natural gas refining equipment. And, rather than just putting it into a pipeline or generating electricity with it, Tonello had another idea.
DAN TONELLO: In the evening, when the trucks are done with their routes, they hook up, fill up.
DAN BOYCE: Grand Junction has been replacing an aging fleet of garbage trucks and buses with natural gas vehicles fueled mostly by the human-sourced gas from the treatment plant. Tonello says Grand Junction is the first city in the nation to do that.
DAN TONELLO: We’re looking at hundreds of thousands of dollars a year being saved by implementing this process.
JOANNA UNDERWOOD, Energy Vision: That’s a model for small wastewater treatment plants anywhere in the country.
DAN BOYCE: Joanna Underwood works with Energy Vision, an environmental group which promotes the use of this renewable natural gas. She says using biogas to run a fleet of vehicles is the most efficient way to use a digester.
JOANNA UNDERWOOD: Every time you convert a bus fleet or a refuse truck fleet or a produce delivery fleet to renewable natural gas, you have had a huge impact.
DAN BOYCE: Because, more often than not, those natural gas vehicles are replacing older, more polluting diesel trucks. Underwood says, if all the organic waste in the country were gathered from dairies, food producers and sewage plants, current technologies could produce enough natural gas to replace about half of the diesel fuel used in the U.S. transportation sector.
And wastewater treatment plants could provide as much as 12 percent of the nation’s electricity, turning waste into a serious powerhouse.”
In addition, a City press release for a National Geographic episode from October 2017 stated, “there were 62 CNG vehicles operating for the City of Grand Junction and Mesa County saving $400,000 per year in fuel costs and eliminating 3 million pounds of carbon per year!”