In theory, the potential for Carbon Capture and Storage (CCS) is huge: by removing the CO2 produced when burning fossil fuels, it can simultaneously reduce levels of harmful emissions and extend the use of traditional energy sources in a low carbon environment. To date, though, a variety of challenges has prevented construction of any plans beyond pilot schemes (the 30MW “Schwarze Pumpe” in Germany being the most significant to date).
The first stage of CCS involves the ‘capture’ of the CO2, carried out through one of several techniques including Oxyfuel, Pre-Combustion and Post-Combustion. Once collected, the CO2 is then liquefied and transported to final storage, usually deep underground in saline aquifers or depleted oil fields. The combined processes are themselves highly energy intensive, using up to 40% of the plant energy. CCS can be implemented either as a ‘new build’ when the plant is first built, or at a latter stage, known as a ‘retro-fit’. On an individual basis, many of the processes are already used in industry: the storage stage, for example, known as Enhanced Oil Recovery, involves pumping CO2 to extract the final remnants from mature oil fields.
Broadly, the challenges around CCS can be categorised as cost, locality and technology. As with many new schemes, costs are high and liable to revisions: estimates for a retro-fit (cheaper than ‘new build’) come in around £1bn and then a further £1m per mile of pipeline.[1] Interconnected with this is the locality factor, with CCS requiring close proximity to suitable storage to avoid expensive transportation. The prospect of onshore storage near major populations has also proved contentious amongst environmentalists.[2] Finally, on a technological basis, none of the processes involved have ever been deployed on a large scale in a joined up manner.
Set against these challenges, if CCS can be made to work, commentators believe the rewards could be significant - particularly for the UK, with its depleting offshore oil fields providing a natural advantage in storage.[3] Furthermore, CCS expertise is highly exportable to the Far East, where the technology could have its biggest impact cleaning up dirty coal-fired plants. It was notable, then, that the British government recently pulled its proposed £1bn funding for retro-fit at Longannet power station, citing concerns over costs. However, ministers did announce that the funds remain available, and indeed could be used in conjunction with money from the European Union CCS competition (to which the UK has submitted a number of proposals).[4] Elsewhere, coherent government policy can help drive CCS investment, especially around carbon floor price.
In sum, there are big challenges to implement industrial scale CCS, but equally big rewards through emission reductions and extension of the energy mix. The UK is well placed to take advantage, but will need industry and government working closely to overcome the unpredictability that arises with investment in new technology, particularly in the current economic environment.
Posted By Robin Macpherson on the 1st of December 2011
[1] Explainer: How carbon is captured and stored, The Guardian, http://www.guardian.co.uk/environment/2008/sep/05/carboncapturestorage.carbonemissions1 5-Sep 2008
[2] Tackling Climate Change, The Economist, http://www.economist.com/node/21534822 29-Oct 2011
[3] Carbon Capture and Storage, The Economist, http://www.economist.com/blogs/blighty/2011/11/carbon-capture-and-storage 20-Nov 2011
[4] Carbon capture in the UK is far from dead, thanks to European funding, Chris Littlecott,
http://www.guardian.co.uk/environment/2011/oct/20/carbon-capture-uk-european-funding?intcmp=122 20-Oct 2011
