The minimal benefits of shutting down all of Ontario's coal-fired power plants didn't justify the cost of the closures, according to a new study from the Fraser Institute.

Air pollution levels decreased slightly as a result of shutting down the plants in Toronto, Hamilton and Ottawa, but installing pollution "scrubbers" on the plants would have created the same effect, according to the study released Tuesday from the Vancouver-based think tank.

The study, authored by Ross McKitrick and Elmira Aliakbari, specifically notes pollution reduction in Toronto and Hamilton was "not statistically significant" with regard to coal plant closures. They cite industrial pollution, emissions from natural gas plants and natural weather conditions as having a greater impact on pollution across the province.

The Fraser Institute's report was authored by economists, who looked at the costs and benefits of removing coal from the power generation system. It points out that electricity prices in the province have gone up due to closing coal plants, something Premier Kathleen Wynne has also admitted led to higher hydro costs for consumers.

Thunder Bay Generating Station

The Ontario Ministry of Energy maintains closing the plants was the right decision.

Spokesman Dan Moulton points out they were "the source of countless smog days." As well, according to Moulton, "closing the plants is... saving us more than $4 billion in annual health care expenses."

However, the Fraser Institute's perspective is the amount of pollution caused by coal-fired plants was not significant enough to see such health improvements.

In a statement, McKitrick pointed out "policymakers in Ottawa should note how Ontario's coal phase out failed to achieve its stated goals."

Coal is still burned to generate around 10 per cent of the country's electricity.