Many might be surprised to know that from Quebec to the Maritime provinces most of Canada's oil is actually imported even though there is plenty of oil available in Western Canada. Every day Canada exports two thirds of the oil it produces mostly south to the U.S. At the same time it imports half the oil it uses.
The claim is that it is cheaper to import oil in the east rather than transport it by pipeline from western Canada. However, as the price of oil increases this may change. Part of the problem is that Canada does not really have a national energy policy. One would think that for reasons of energy security alone Canada would ensure that domestic oil would flow into the east so that Canada was not dependent upon foreign oil.
However, the west particularly Alberta is wary of a national energy policy. The last such policy was pursued in 1980 by Pierre Trudeau. The policy made Big Oil and Big Alberta hopping mad. It even included a publicly owned national oil company a no no to the big oil capitalists who run our oil enterprises for us. If a publicly company makes money it should be privatized as happened to Petro Canada. Profits are for corporations. For more see this article.
Actually Canada does have a national energy policy. The first plank is to provide oil and gas and electric power to the U.S. NAFTA ensures this. Second is to ensure that the large energy corporations make money in their Canadian operations. Canada is now trying to increase production and enter Asian markets.