"Harnessing Green Energy" - Novae Res Urbis

Friday, July 30, 2021

NRU Publishing

Marc Mitanis

In 2022, the City of Toronto will begin using renewable natural gas produced from the city’s organic green bin waste to fuel city vehicles and heat city-owned facilities, resulting in a significant reduction in greenhouse gas emissions from municipal operations.

In partnership with Enbridge Gas Inc., the City of Toronto has equipped the Dufferin Organics Processing Facility near Dufferin Street and Finch Avenue West with biogas upgrading infrastructure that enables the creation of renewable natural gas from the raw biogas produced from processing organic green bin waste. Starting in 2022, the city will begin using the renewable natural gas that is now being produced from the waste and is being stored in the natural gas grid to power city- owned facilities and city waste collection vehicles.

City of Toronto solid waste management services general manager Matt Keliher said that the project, which is one of the first of its kind in North America, is ultimately a way for the city to forge ahead with a low-carbon economy.

“We’re investing in the capture of greenhouse gases that would have otherwise been flared or burned off into the atmosphere,” Keliher told NRU. “We’re able to convert that energy into a renewable natural gas that goes into the pipeline that the city can utilize for its buildings and also in the fleet that we have which runs on natural gas.”

The city collects approximately 170,000 tonnes of organic material through its green bin program each year, and 55,000 tonnes are currently processed by the Dufferin Organics Processing Facility. The city’s other organics processing plant at Disco Road in Etobicoke processes 75,000 tonnes of organic waste every year. Both facilities employ anaerobic digestion technology to break down organic waste to produce digester solids—used to create compost—and biogas, which is composed of methane gas, carbon dioxide and other elements that can be upgraded to renewable natural gas.

The renewable natural gas produced by the Dufferin facility will be blended with the natural gas purchased by the city to create low-carbon fuel for municipal use. The facility will produce 3.3 million cubic metres of renewable natural gas every year. Capturing the biogas instead of burning it off will avoid over 9,000 tonnes of carbon being released into the atmosphere on an annual basis.

Calling the project a “very important investment in green infrastructure,” ward 6 York-Centre councillor James Pasternak said the production of renewable natural gas will help the city achieve its TransformTO target of net-zero greenhouse gas emissions by 2050.

“It is a really transformational project that could not only help move towards our climate change [mitigation] goals, but that also uses and reuses organics and waste in a positive way,” Pasternak told NRU. “I think in the long run, people will look back at this decision as somewhat historic in our road to net-zero emissions by 2050, and making sure we have as clean a city as possible.”

Toronto Environmental Alliance waste campaigner Emily Alfred said that renewable gas capture from organics processing facilities shows how addressing a waste issue can also help meet climate change goals.

“Food and organics make up roughly 50 per cent of household waste,” Alfred told NRU. “Keeping organics out of landfills is a major benefit, because organics in landfills break down and create methane, a major greenhouse gas.”

The project is the first in a series of biogas and landfill gas upgrading opportunities that the city has identified. Renewable natural gas infrastructure is expected to be installed at the Disco Road Solid Waste Management Facility in Etobicoke by the end of 2023, with potential landfill gas upgrading to occur at the Green Lane and Keele Valley landfills sometime after that. Once up and running, the four sites should be capable of producing enough gas to meet the city’s entire annual natural gas needs.

“I think it’s pretty cool that the city’s waste will be fueling the trucks that are collecting that waste, which will create this nice circular loop,” Alfred told NRU. “I think this is a really encouraging example of how to reduce waste emissions, transport emissions, and reduce natural gas use in buildings.”

The city is planning to build a third anaerobic digester to handle the volume of organic waste being produced by residents and businesses. Alfred said a third organics processing facility would help keep organic waste out of landfills while producing renewable green fuels.

“There are a lot more organics that are being generated in the city right now than the city can process, and there’s also a whole group of multi-residential buildings that don’t even have city waste collection,” Alfred told NRU. “When we take a step back and look at how these organics could be processed locally, keeping them out of landfills, they could actually be creating green local energy.”

Enbridge Gas manager of renewable natural gas Gordon Lau said that Enbridge is assisting the city with early screening and study of the Disco Road and Green Lane Landfill projects, and is working to partner with other municipalities on future renewable natural gas opportunities.

“Renewable natural gas presents a tremendous opportunity for municipalities to affordably and practically reduce emissions, leveraging existing energy infrastructure,” Lau told NRU. “This technology has the added benefits of diverting waste, stimulating regional economic development and creating local jobs at lower cost than electricity.”

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Posted with permission of the publisher of NRU Publishing Inc. Original article first appeared in Novae Res Urbis – Toronto, Vol. 25, No. 30, Friday, July 30, 2021.