For decades, oil companies have been injecting liquid carbon dioxide (CO2) into the ground to get more oil from their wells. It’s a process called enhanced oil recovery (EOR), and it works because CO2 acts as a solvent to free up oil that’s stuck in rock formations.
EOR has unintended environmental benefits too, because a lot of that CO2 stays in the ground instead of going into the air. For that reason, a lot of today’s experimental carbon capture and storage (CCS) technologies are based on processes pioneered in EOR.
Now Canadian energy provider SaskPower has become the first to combine the two practices on a commercial scale with the new CCS facility it opened at its Boundary Dam Power Station in Estevan. Ten years in the making, the new CCS plant is designed to capture up to 1 million tonnes of carbon dioxide (CO2) per year, which is equivalent to removing 250,000 cars from the road. At least some of the CO2 it captures will be sold to Cenovus Energy Inc, which will inject it into the ground below its Weyburn oil field so it can get more oil from its fading wells.
SaskPower says the deal’s a win-win: one win for the environment (by extracting CO2 from the emissions of coal-fired power plants top combat climate change) and one win for the bottom line (by pumping out more oil) – although the jury’s still out on the size of the environmental benefit once you account for the emissions from the extra oil being extracted.
That accounting is critical, because this project only the first of what promise to be hundreds of other combined EOR-CO2 projects around the world.
“This project is important because it is applicable to about 95 per cent of the world’s coal plants,” said Canadian Economy Minister Bill Boyd at the plant’s unveiling. “As nations develop emission regulations, they will come to us to see how we continue to provide affordable coal power to customers, but in an environmentally sustainable way.”