Portlanders may be speaking a lot about Poop to Power this summer, when the city treatment plant expects to begin converting sewage into renewable natural gas.
But eggshells, chicken bones and rotting produce won't be part of the mix, now that Metro has scrapped talks with Waste Management Inc. to collect the region's food scraps and turn it into energy at the same city plant. In December, Metro ended nearly a year's negotiations with Waste Management — which was partnering with the city Bureau of Environmental Services — after failing to reach agreement on the price and volume of food scraps to be processed at the bureau's Columbia Boulevard Wastewater Treatment Plant in North Portland.
Metro says it will stick with its ambitious five-year timetable to require food processors, groceries, schools and other major operations to set aside food scraps for recycling, but will go back to the drawing board to figure out where that material will be processed into energy. Meanwhile, much of that food waste will be hauled by truck more than two hours to the state's lone facility that turns such organic waste into energy, a Junction City plant owned by Shell New Energies.
The city could have earned $800,000 to $900,000 worth of energy a year from the food scraps, plus tipping fees for disposing of the material, said Paul Suto, the Bureau of Environmental Services engineering manager overseeing the Poop to Power project.
However, he added, "the impact on the Poop to Power project isn't really significant."
That's because the city previously decided the Poop to Power project could pencil out without the food scraps component, given the surging market value of renewable natural gas, he said.
The Poop to Power project figures to cost about $16 million when it's fully operational in July, Suto said. The resulting renewable natural gas, to be sold to NW Natural, is expected to fetch as much as $10 million a year, he said. That would put the facility on track to pay for itself in four to eight years, as promised when the Portland City Council approved the Poop to Power project in the spring of 2017.
As recently as 2016, independent analysts concluded that the biogas project, which eventually was dubbed Poop to Power, wouldn't work financially without more "feedstock" to pour into the treatment plant's anaerobic digesters and produce energy.
Janice Thompson, the Citizens' Utility Board's independent consumer advocate who monitors the Portland water, sewer and storm drainage utilities, wrote a report in February 2016 concluding the project wouldn't work without the bureau adding an organic waste component. That would be food scraps or, if those couldn't be procured, fats, oils and greases now trapped separately by restaurants and food processors, so they don't muck up the city's pipes and sewage treatment system.
"The biogas project does not appear to have an adequate payback unless the organic waste receiving facility is built," Thompson wrote in a Feb. 29, 2016, report to the Portland Utility Board, a city advisory panel that monitors the Water Bureau and Bureau of Environmental Services. Thompson says at her urging, the Bureau of Environmental Services determined that it could add fats, oils and greases to the project if Metro's food scraps plan couldn't deliver the necessary feedstock.
A March 17, 2016, report by a city budget analyst reached the same conclusion. "The economic viability of the biogas reuse project without the organic waste receiving facility is uncertain," the analyst wrote. "Current forecasts of the bureau show these projects together could recover costs and result in a small net benefit in 15 years or less."
But Suto, who is the overall Poop to Power project manager, says much changed by the time the bureau brought it to the City Council for approval just 13 months later.
For one, the bureau determined it could produce more than three times as much energy from sewage, he explained. And the prices for selling renewable natural gas got much more lucrative.
The actual value of the gas as energy is relatively minor, currently about 10 percent of what the city expects to fetch, Suto said. The bulk of the money comes from economic incentives for producing alternative renewable energy via three programs: the federal Renewable Fuels Standard and low-carbon fuel standards adopted by California and Oregon. Those have incentives to promote vehicle fuels with a lower carbon footprint than energy produced from fossil fuels.
The bureau had decided it was too risky to proceed with Poop to Power while banking on feedstock from the Metro food scraps program, Suto said, and designed it as a stand-alone project.
Expanding into the FOG
Now the bureau will design a smaller addition to turn fats, oils and greases — known in the industry as FOG — into energy, he said. That could produce $300,000 to $400,000 worth of energy a year, which will be used to power the treatment plant, he said. The bureau gets even more than that for a tipping fee to dispose of the material.
The bureau is working on designs and expects to propose that component to the City Council this spring, Suto said.
"We're looking at those costs right now. We're targeting a 10-year payback on that facility."
That organic waste receiving facility could eventually be expanded to accommodate food scraps.
"We'll try to keep some flexibility to expand in the future if there are future opportunities with Metro," Suto said.
As Metro explores cheaper ways to process food scraps, one of the logical places to go are sewage treatment plants in Portland, Gresham and Washington County, because they already have anaerobic digesters needed to process the material — and are innovators in achieving environmental objectives in their operations.
Waste Management, the nation's largest solid waste company, also could be back to propose smaller projects.
"We're not giving up," said Jackie Lang, the Houston-based company's spokeswoman for the Northwest. "We're not done yet."
Quality local journalism takes time and money, which comes, in part, from paying readers. If you enjoy articles like this one, please consider supporting us.
(It costs just a few cents a day.)