Open this photo in gallery The office of Alberta Premier Jason Kenney, seen here on Feb. 4, 2020, said his numbers on Friday reflect what emissions the government considers would count towards the cap. Ryan Remiorz/The Canadian Press

There is a 20-megatonne gap between what Alberta and Ottawa say are the emissions from the oil sands, meaning the energy sector is either swiftly approaching a provincially legislated emissions limit or there is ample room to grow before companies need to seriously curtail greenhouse gasses.

Alberta Premier Jason Kenney was looking to burnish the environmental credentials of the oil sands during a trip to Washington on Friday and said its emissions are either 67 or 68 megatonnes this year, far below the province’s 100-megatonne cap. However, data from the federal government shows emissions from the oil sands that fall under Alberta’s legislated cap will total 87 megatonnes this year. That’s up from 68 megatonnes in 2015.

The two numbers tell different stories about how close the oil sands are to reaching the emissions limit created by Mr. Kenney’s predecessor in 2016. The federal findings suggest the province is rapidly nearing the cut-off, while the Premier has used his low number as a justification for why Ottawa should approve a proposed mine from Teck Resources Ltd.

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Ottawa’s looming decision on whether to approve the massive new oil sands development depends partly on whether the province’s emission cap is credible, as the Liberal government nervously eyes the country’s growing carbon emissions. Canada has committed to reaching net zero emissions nationally by 2050.

“Right now, we’re at about 67 or 68 megatonnes per annum of CO2 emissions from the Canadian oil sands. Teck Frontier would add about four megatonnes, taking us to the low 70s,” Mr. Kenney said while speaking at the Wilson Centre on Friday.

When then-premier Rachel Notley’s New Democrats introduced the emission cap in 2016, the Alberta government estimated emissions at about 70 megatonnes. Oil sands production and its related emissions have only climbed since, as existing mines have added more capacity and a number of smaller projects have been built.

According to the Canadian Association of Petroleum Producers, oil sands production is supposed to increase to 3.2 million barrels a day this year from 2.91 million barrels a day in 2018.

A federal report submitted to the United Nations in January estimated emissions from the oil sands will hit 94 megatonnes by the end of 2020. The report found that emissions hit 71 megatonnes in 2015 and 81 megatonnes in 2017.

Alberta’s emissions cap legislation defines emissions from the oil sands as total emissions, less new upgrading after 2015 and emissions from the production of electricity sold to the provincial grid. Subtracting those exempted emissions brings Ottawa to the 87-megatonne oil sands emissions assessment for 2020.

Mr. Kenney’s office said his numbers on Friday reflect what emissions the government considers would count towards the cap. They did not explain the difference between the Premier’s numbers and those put forward by Ottawa.

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The province has never introduced regulations, so the emissions cap cannot be legally enforced and the province has never explained how it will work. The cap was announced in conjunction with Ottawa’s decision to purchase and build the Trans Mountain Pipeline expansion project. While the Alberta government has indicated some emissions won’t count towards the limit, experts say there is uncertainty about which emissions will be included.

Alberta Environment Minister Jason Nixon insisted on Friday that oil sands emissions are “nowhere near” the 100-megatonne cap, even with the addition of the Frontier mine. He said the government has no immediate plans to pen regulations for the cap.

“If that is the lens the federal government is looking at this project through, then approve it, because we’ve already met those requirements,” Mr. Nixon said.

The Pembina Institute, an Alberta-based environmental think tank, has calculated emissions of 82 megatonnes by the end of the year.

Alberta needs to provide data justifying Mr. Kenney’s figures, according to Chris Severson-Baker, the group’s Alberta director. “The burden of proof is on Alberta to show its data and accounting are credible in the eyes of the international community," he said.

Andrew Leach, an environmental economist at the University of Alberta, warned that it’s difficult to look at annual emissions projections without clear definitions from the province on what emissions will be included in the cap.

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“It’s easy to say we’re far away when no one knows what the measure is,” he said. “But if we have a 100-megatonne cap and we’re trumpeting it as a reason we shouldn’t worry about oil emissions, at some point we’re going to have to decide which projects can’t play."

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