A Little Leak

The Alberta Government has invested two billion into carbon capture and storage (CCS) technology, hoping to sequester the province’s emissions deep within the earth. As one of the only provinces to rely heavily on coal-generated power (Alberta currently has nine coal-fired facilities), and one whose economy relies heavily on oil and gas, this sequestration is an essential part of the province’s overall energy strategy.

In the province, the University of Calgary, in particular, has made a name for itself in the field. Its research is coordinated by the Institute for Sustainable Energy, Environment and Economy (ISEEE). The ISEEE also provides a central online location for its own reports and others’, exploring the complex issue.

According to the university’s researchers, the Wabamun Area CO2 Sequestration Project (WASP) demonstrates that the costs of injecting CO2 and storing it in geologic formations are relatively low — about $3 per tonne of carbon dioxide. The cost to capture the CO2, pressurize it and transport it from the site where it was generated, however, would be about 10 times more than the cost of storage.

But beyond costs, one of the biggest questions about CCS technology is whether it can permanently sequester CO2. Obviously, if the CO2 leaks out, the entire point of the exercise is moot.

But just how much leakage is too much? That number, it turns out, is very small: one per cent.

According to research published in Nature Geoscience, unless CO2 leakage can be kept below one per cent of the reserve per year, CCS will not be able to mitigate the effects of climate change, such as rising sea levels and ocean acidification.

The severity of a one per cent leak decrease as the periods of time increase (from years to decades to centuries), but such a leak wouldn’t actually be problem-free until the thousand-year mark. It’s a huge span of time, but when it comes to waste disposal of any kind, we’re definitely talking about the long haul.