The Shepard Landfill Solar Project in Alberta provides power directly to Calgary’s composting plant while avoiding the generation of 3,600 tons of annual greenhouse gas emissions.Supplied
For decades, landfills and other contaminated sites across North America have found a new life as parks, golf courses, housing and retail projects – and more recently as methane gas capture facilities and solar hubs that can power municipalities and generate revenue through energy market sales.
Efforts to give landfills a fresh start gained momentum in the late 1970s with U.S. legislation aimed at spurring development of brownfield properties, former industrial and commercial sites which typically contain hazardous waste or pollution.
In 1989, the National Contaminated Sites Remediation Program was established in Canada.
And while putting buildings on top of land formerly used as garbage dumps presents challenges with preventing the settling and leaching of gas, that hasn’t stopped developers – in places where land scarcity justifies the cost – from building malls and hotels on long-shuttered sites.
Sports facilities and relatively light structures are common types of development on these sites, such as the film production studios, warehouses and offices built on a former landfill at Montreal’s Technoparc.
Landfills have also functioned as an incubator for engineering innovation and a living laboratory where properties of renewable natural gas (RNG), such as landfill gas, can be studied. According to a 2022 report from Fortune Business Insights, landfill gas processing is expected to expand into a US$5.2-billion global market by 2028.
“RNG represents a tremendous opportunity to provide affordable, reliable and low-carbon fuel to meet Canada’s increasing energy needs, leveraging our existing energy system and stimulating economic growth,” says Cynthia Hansen, executive vice-president of energy provider Enbridge, which partnered with Walker Industries and Comcor Environmental Ltd. to jointly develop renewable gas projects across the country.
Enbridge says Canada has more than 10,000 landfill sites that account for 20 per cent of national methane emissions with only a third of the emissions captured and utilized. The renewable natural gas industry estimates that landfill-derived gas could potentially power 400,000 homes a year.
The Green Lane Landfill, in St. Thomas, Ont. Enbridge says Canada has more than 10,000 landfill sites that account for 20 per cent of national methane emissions with only a third of the emissions captured and utilized.Peter Power/The Globe and Mail
Along with gas capture, solar panels on landfills are another area of growth in land repurposing in the U.S. and Europe, with pressure to meet emissions targets creating an uptick in interest in landfill-to-solar projects in this country, especially in Western Canada.
In Calgary, landfills are becoming prime real estate for large solar farms with the city exploring options for developing solar assets on both municipally owned active and closed landfills, as well as on other brownfield sites.
“We are continuing to assess renewable development and other uses on these sites,” says Cory DeFraine, senior energy engineer, climate and environment, City of Calgary. “This is one of many actions we are taking under our Climate Strategy to achieve net-zero emissions by 2050.”
According to a 2021 report by the U.S.-based non-profit the Rocky Mountain Institute, millions of acres of idle landfill sites in North America are candidates for conversion to ground-based solar panel farms.
Blessed with abundant sunshine, along with an open market electricity system where private power producers can sell directly to buyers, Alberta has seen a burst in utility-level solar energy project development since the first phase of the Calgary Shepard Landfill Solar Project was completed in 2018. The installation provides energy directly to the city’s composting plant while avoiding the generation of 3,600 tonnes of annual greenhouse gas emissions.
Private development of solar on brownfield sites in Calgary include the ATCO Group’s Barlow and Deerfoot projects, Western Canada’s largest urban solar projects.
Meanwhile, the City of Saskatoon and its partners have installed 92 solar photovoltaic panels to produce energy to provide 40 per cent of the power for a nearby landfill gas facility and in Dawson City, Yukon, a solar power project has been built on a former landfill.
Ottawa is exploring the idea of establishing a future solar project at the former Nepean landfill site, says Andrea Flowers, the city’s strategic projects manager.
“Some city policy documents include language which allows for or supports solar projects,” she added, referring to Ottawa’s new Official Plan which states “intensification is encouraged on former industrial or commercial sites, including brownfield sites where feasible.”
According to a 2021 report by the U.S.-based non-profit the Rocky Mountain Institute, millions of acres of idle landfill sites in North America are candidates for conversion to ground-based solar panel farms.
Solar panels that can be linked to power grids via existing landfill connections are mounted with lightweight ballasts to prevent sinking and leaching, though leachate collection systems are often installed as well.
There is “a full-court press” for solar development on landfills and brownfields in the U.S., says Christopher De Sousa, a professor at Toronto Metropolitan University’s School of Urban and Regional Planning.
“Repositioning of landfills is booming business in the U.S.,” he says. In Canada, “not so much.”
A landfill site near Brooks, Alta., on Oct. 22, 2012. According to a 2021 report by the U.S.-based non-profit the Rocky Mountain Institute, millions of acres of idle landfill sites in North America are candidates for conversion to ground-based solar panel farms.Jeff McIntosh/The Canadian Press
Fernando Carou, manager of renewable energy and net-zero development with the City of Toronto, says landfill to solar became uneconomical after the winding down of the feed-in-tariff subsidy that had guaranteed above-market rates for clean energy producers in the province.
He says the city is focused on converting waste sites to parkland and other best uses, and on promoting solar energy on rooftops, carports and city facilities.
The city is also remediating brownfields, notably through the jointly funded $1.25-billion Port Lands project along the waterfront, which Infrastructure Canada calls “one of the largest waterfront revitalization efforts ever undertaken in the world,” that will open lands for development in the future.
Dr. De Sousa says Toronto has a long history of repurposing brownfields, formerly industrial lands that are potentially contaminated – and of reclaiming waste sites, such as Etobicoke’s Centennial Park, which was built on a municipal dump.
He says a push for renewable energy on brownfields in Ontario ran into a wall when the Progressive Conservative government came into power in 2018 and cancelled hundreds of renewable energy projects.
“We’ve stepped back and that’s too bad. I drive in Toronto and see one wind turbine [on the grounds of Exhibition Place],” he says. “I would have thought there would have been more to come, but apparently not.”