Everyone keeps saying that oil sands is where the sure money is going in oil right now (forget frying the climate in the process), but costs just keep rising.

One of the leading oil sands firms, Canadian Natural Resources has admitted that costs for its Horizon oil-sands project have risen to as much as $8.7 billion (Canadian), $1.9 billion more than initial estimates, as severe cold at its northern Alberta project site hampered construction.

Canada’s second-biggest oil explorer said construction at the site north of Fort McMurray, was 90 per cent complete and Horizon remained on track to open in August, as it decided to spend the additional cash in order to stick to the schedule. It’s the third time that Canadian Natural has raised its cost estimate.