The recent launch of a large-scale power station retro-fitted with carbon capture and storage (CCS) is an important step forward in addressing climate change.  It is no criticism to add that many issues surrounding CCS remain to be resolved.

The world will be highly dependent on coal as an energy source for many years to come.  Coal-fired power stations are a major source of carbon dioxide (CO₂) emissions which accumulate in the atmosphere, contributing to global climate change.  If CCS can be made to work at power stations in various circumstances around the world, then it will be less difficult than it would otherwise be to reduce CO₂ emissions on a scale which will substantially mitigate climate change while ensuring that there is enough energy to support economic growth and development.  Note that I do not say it will be easier: the ideas of ‘ease’ and ‘addressing climate change’ simply do not go together.

It is therefore very good news that SaskPower has re-built and fitted with carbon capture technology an old coal-fired power station at Boundary Dam, Saskatchewan, Canada.  Its website gives an interesting overview of what the carbon capture facility looks like and how it works (1).  However, there is no need to rely on the company’s own evaluation of its achievement.  The International Energy Agency has hailed it as a “historic milestone” and stated that “the experience from this project will be critically important” (2).

Some 20% of the project cost was funded by the Canadian government (3).  No doubt there was an element here of supporting an infant industry, seeking to reinforce Canada’s position as a global leader in CCS technology.  Nevertheless, it is very much to the credit of Canada, a country less at risk from climate change than many others, and perhaps potentially a net gainer via improved agricultural yields and reduced heating costs, that it should have committed funds to a project designed to reduce CO₂ emissions.  Moreover, this is exactly the sort of low-carbon investment that is appropriate for government support – an innovative facility which may demonstrate the feasibility of a technology and provide lessons which may enable others to apply the technology more effectively or at lower cost.  By contrast, the case for using public funds to support large-scale investment in a particular generation of low-carbon technologies that may soon be superseded – subsidies for homeowners to fit solar panels, for example – is much more dubious.

The implications of the storage aspect of CCS are easy to overlook.  While the success of the capture aspect can be ascertained quite rapidly, it would be premature to state that a CCS project works until the effectiveness of the storage has been demonstrated over a period of years.  There is little point in incurring large costs to capture and store carbon if a significant proportion will eventually find its way into the atmosphere via gradual leakage from store, or sudden release triggered by some unforeseen event.  There can also be local risks to humans and wildlife from releases of CO₂ (4).  Reliable storage is partly a technical problem of identifying suitable chemical and physical forms and locations in which to store carbon, the range of options under consideration being quite wide (5).  But there is also an institutional problem of ensuring that, once carbon has been transported away from a power station, someone will be responsible for preventing leakage, for monitoring to detect any leakage, and for taking suitable action if leakage should occur.

In the case of Boundary Dam, there are two destinations for the captured carbon.  Some will be stored some 3 kilometres underground in Aquistore, a facility administered by the Petroleum Technology Research Centre, a not-for-profit body accountable to the Government of Saskatchewan and other Canadian public bodies (6).  However, the main destination appears to be nearby oil fields, where it will be sold and used for enhanced oil recovery, and this revenue stream is critical to the project’s financial viability (7).  This prompts several questions.  Once the carbon has passed to a company whose priority is oil production, will prevention of carbon leakage be given adequate attention?  Who will be responsible for the carbon once an oil well runs dry?  And can the costs of CCS be sufficiently reduced that it will be financially viable without the need to rely on public subsidy or local demand for the captured carbon?

Notes and references

1. SaskPower CCS http://www.saskpowerccs.com/
2. International Energy Agency, Press Release 1 October 2014 http://www.iea.org/newsroomandevents/pressreleases/2014/october/iea-hails-historic-launch-of-carbon-capture-and-storage-project.html
3. MIT Carbon Capture & Sequestration Technologies Program: Boundary Dam Fact Sheet https://sequestration.mit.edu/tools/projects/boundary_dam.html
4. Wikipedia: Carbon capture and storage – Leakage http://en.wikipedia.org/wiki/Carbon_capture_and_storage#Leakage
5. Wikipedia: Carbon capture and storage – Sequestration http://en.wikipedia.org/wiki/Carbon_capture_and_storage#Sequestration
6. Petroleum Technology Research Centre – About Us http://ptrc.ca/about-us
7. Goldenberg S, The Guardian. 1 October 2014 Canada switches on the world’s first carbon capture plant http://www.theguardian.com/environment/2014/oct/01/canada-switches-on-worlds-first-carbon-capture-power-plant  See Yeates quote, 4^th paragraph from end.