While the Fraser Institute rails against increasingly burdensome climate change policies that it believes are toothless and sometimes "ugly" obstructionism in Canada, Cann believes the oil sands industry's main challenges lie in being a high-cost resource and finding a new market now that the US is swimming in shale oil.

While he is a big-picture bull for oil and gas, when he returns to Calgary to become a partner in Deloitte's Canadian oil and gas practice to be closer to his two children in Toronto, Cann knows he'll be entering an industry in flux.

Alberta's New Democratic Party is rushing ahead with implementing its climate change plan, including a proposed cap on oil sands emissions, which the Fraser Institute believes will leave hundreds of billons of dollars' worth of oil in the ground while doing little to reduce global greenhouse gases.

A recent study by the institute's senior director of natural resource studies Ken Green and senior policy analyst Taylor Jackson estimates that Alberta's proposed cap of 100 megatonnes of emissions will cut the industry's production by more than three billion barrels of oil cumulatively between 2025 and 2040.

This will cost the economy more than $C250 billion ($A253.93 billion) in lost production over that time result in a meagre 0.035% reduction in global greenhouse gas emissions by 2040.

Green said there was a "serious imbalance" between the high costs of Alberta's proposed carbon emissions cap to the economy and the minimal benefits that could be realised in greenhouse gas emission reductions.

Current projections show oil sands operations could hit 100 megatonnes of emissions by 2025.

The study also finds capping emissions in the oil sands will, at most, only reduce carbon emissions by 236 megatonnes cumulatively between 2025 and 2040, and at a cost of $250 billion that equals more than $1000 to abate just one tonne of emissions.

By comparison, British Columbia currently prices carbon emissions at $30/t.

However, Cann told Energy News that it is the market movements across Canada's southern border that were causing some of the biggest headaches for the country's oil sands industry.

"The challenge of the Canadian heavy oil industry is that it's a high-cost resource. It's economic when oil prices are high and when they go down it gets very challenging for projects to be successful," he said.

"The second challenge is that there's only one market for their product: the US. Canada has never needed to export the product internationally. So all of our infrastructure points to the US, and the Americans have discovered shale oil, and it's abundant."

With the demand for Canadian heavy oil falling, Cann believes the next problem for Canada is how to open export markets.

"There is lots of opposition to moving crude oil around these days due to various high profile disasters like Gulf of Mexico, so communities are very skittish now about the potential for petroleum product spills in their neighbourhoods, and want to see a much higher standard of performance," he said.

"That goes on all oil and gas projects. Even in the US there is opposition to pipelines in the Marcellus and Bakken for the same reasons."

Violence broke out yesterday at a hearing of Canada's National Energy Board which was taking public comment and testimony regarding the Energy East Pipeline.

The meeting was cancelled after an anti-pipeline activist charged at the three-member panel of Energy Board commissioners, and had to be forcibly restrained.

CBC reported that the table in front of the commissioners was "almost" knocked over, in scenes which the Fraser Institute called the "ugly face of pipeline obstructionism in Canada".

Canada gets 25-30% less per barrel than other types of crude oil sold internationally, and the Fraser Institute says that with oil sands production to grow as global demand picks up and oil price keep firming up, "there's still more to lose".