Alberta oilsands plants have slowed the growth rate of their carbon emissions by becoming more efficient in their role as Canada’s top natural gas user, according to IHS Markit. 

An updated production survey released Wednesday showed a 20% reduction of average oilsands greenhouse gas (GHG) emissions since 2009 on a scale known as “intensity.”

Instead of total volume, the yardstick measures emissions caused per barrel of output by burning gas in heat processes used for oilsands production, especially to make steam for underground bitumen extraction.

IHS said its new oilsands carbon emissions survey confirmed a trend foreshadowed by 2018 research that projected a 16-23% decline as of 2030, down to a level 30% below the 2009 intensity peak.

The consultancy cautioned...