Waterloo Region to save millions by converting sewer gas into electricity at treatment plants

WATERLOO REGION — A project to capture waste biogas from treating sewage will cut the Region of Waterloo’s electricity bills by millions of dollars and reduce damaging greenhouse gases.

The project will use the biogas that’s produced at the region’s three largest sewage treatment plants to generate electricity and heat the buildings.

Some of that gas is now used as part of the sewage treatment process, while the rest is burned off.

“We think it’s a fantastic project,” said Pam Law, the Region of Waterloo’s senior project engineer for the project.

“We’re taking something, biogas, which is really a renewable resource because we’re always producing it, and we can take it and use it more effectively and efficiently. It’s better for the environment and it’s also more economical.”

Once the system is in place, by mid-2020, it will produce about 12,000

megawatt-hours of electricity every year, which is the amount of electricity used by 1,200 houses per year.

The largest plant, at 368 Mill Park Dr. in Kitchener, will see its power bills cut by 60 per cent, while bills at the other two plants, 230 Water St. S. in Cambridge and 340 University Ave. E. in Waterloo are expected to decrease by 40 per cent.

This project is expected to save the region almost $17 million in electricity bills over the next 20 years, and is expected to pay for itself in about nine years, Law said.

There’s an environmental benefit, too, since using gas that’s now being burned away will reduce the region’s emissions of greenhouse gases, which contribute to climate change.

The three biogas cogeneration plants combined would reduce emissions by about 550 tonnes of carbon dioxide each year, equivalent to taking around 115 cars off the road.

At a series of open houses in November and earlier this month, residents expressed concerns about potential noise and smells from the cogeneration.

“In general, the public was very supportive of the project,” Law said.

“There were a few concerns raised from residents living adjacent to the wastewater treatment plants. But we were able to tell them that the new cogeneration facilities, located on the plant sites, will not be noisy, will not smell and will be safe.”

The buildings will have noise dampening features and silencers in the exhaust stack. The plants are expected to generate about 30 decibels of noise, about the noise level you’d get in a library, according to a report by consultants CH2M.

The region operates 13 waste water treatment facilities, but the other plants don’t generate biogas in sufficient amounts to make it worthwhile to capture the biogas and generate electricity.

The plants separate waste into liquids and solids, treat liquid waste to provincial standards and send it into the Grand River; solid waste is treated and either spread on farm fields as fertilizer or sent to landfill.

Construction on the project is expected to start in a year and wrap up in July 2020.

The region has set aside $24.1 million for the project. Provincial incentives will contribute almost $2.8 million.

More information is available at www.regionofwaterloo.ca/water under “master plans and projects.”