Tuesday, December 24, 2013

Carbon Capture and Storage: An Update

If carbon capture and storage could be accomplished at a reasonable cost--and that "if" is absolutely enormous--the implications for the question of climate change are extraordinary. At least some of any needed reduction in emissions could happen while still burning fossil fuels. The Australian-based Global CCS Institute describes the potential and the issues facing carbon capture and storage in its annual report, The Global Status of CCS--2013. For the record, this Institute was established in 2009 with initial funding from the government of Australia, and its members "include national governments, global corporations, small companies, environmental non-government organisations, research bodies and universities." It seems to me a bit of a cheerleader for the potential of carbon capture and storage approaches, but it still offers a useful overview of where the technology stands at present. 

The report envisions a future in which CCS technology would account for perhaps 15% of reduced carbon emissions by 2050, compared with the baseline that would otherwise exist. The argument is that if carbon emissions are going to be cut, then CCS technology will be cost-effective compared with some of the other options. The report argues (citations omitted): 

"CCS has strong potential to be cost competitive in a low–carbon future. The International Energy Agency (IEA) has estimated that the exclusion of CCS as a technology option in the electricity sector alone would increase mitigation costs by around US$2 trillion by 2050. This is because many alternatives to CCS as a low–emissions technology in the electricity sector are more expensive. ...
Beyond the electricity sector, it is unlikely that energy–related and process CO2 emissions can be eliminated without CCS. This is because CCS is the only large–scale technology available to make deep emissions cuts in several industrial sectors (such as iron and steel and cement). Industrial sector emissions account for more than 20 per cent of current global CO2 emissions. It follows that the widespread deployment of CCS in the power and industrial sectors in the coming decades is imperative to achieving a low–carbon energy future at least cost."
I tend to think of carbon capture and storage as a largely unproven technology. Here, the report dances a delicate line. It argues on one hand that the basics of CCS are well-understood. But it also argues that very large changes are needed if CCS is to be a major player in future carbon reductions. Here's a sample of the encouraging discussion:

"CCS is often mistakenly perceived as an unproven or experimental technology. In reality, the technology is generally well understood and has been used for decades at a large scale in certain applications. For example:
  • large–scale CO2 separation is undertaken as a matter of routine in gas processing and many industrial processes
  • CO2 pipelines are an established technology, on land and under the sea
  • large–scale injection and geological storage of CO2 has been safely performed in saline reservoirs for more than 15 years, and in oil and gas reservoirs for decades.
There are currently 12 operational large–scale CCS projects around the world, which have the capacity to prevent 25 million tonnes a year (Mtpa) of CO2 from reaching the atmosphere. The key technical challenge for widespread CCS deployment is the integration of component technologies into successful large–scale demonstration projects in new applications such as power generation and additional industrial processes."

There's a lengthy discussion of the large-scale projects that exist, and others that might be considered. There is also a lengthy discussion of various hurdles that need to be overcome. Here are some examples:

"More than 90 per cent of the overall cost of CCS can be driven by expenses related to the capture process. ... There is a variety of R&D programs focused on developing new and more cost-effective capture technologies. For example, the US DOE’s National Energy Technology Laboratory (NETL) has R&D programs designed to explore new solvents, membranes, and sorbents that could be used for CO2 capture. These programs focus strongly on developing technologies at the bench scale, and then funding their transition through to pilot scale."
"For CCS to meet the longer term climate challenge of restricting global warming to less than 2°C, the estimated magnitude of the CO2 transportation infrastructure that will need to be built in the coming 30–40 years is 100 times larger than currently operating CO2 pipeline networks."
"[T]here is an urgent need for policies and funded programs that encourage the exploration and appraisal of significant CO2 storage capacity."
"Between 2008 and 2012, 'policy leader' governments committed more than US$22 billion in direct funding to large–scale CCS demonstration projects. ... In late 2009, the scale of funding support being considered globally exceeded US$30 billion. However, as the global financial crisis deepened, some funding mechanisms were cancelled before they could be legislated ... To date, not all of the available funding has been taken up. In several jurisdictions, some of the funding is no longer available due to legislative limits or changing government priorities. In some situations, the value of available government commitments has decreased due to the structure of funding mechanism or the funding is difficult to access due to the design of programs. In total, funding commitments have been reduced by more than US$7 billion ..."

In short, carbon capture and storage technology needs lots of basic research on the technologies for capturing carbon, and on the infrastructure for transporting it, and for where it would be stored. Meanwhile, funding commitments are dropping. The report sums up the situation this way:

"CCS is at something of a crossroads. For those immersed in a highly challenging environment with often slow-moving funding and policy commitments, it would be very easy to put the commercial deployment of CCS in the ‘too difficult’ basket. However, for those with an eye to the very real challenges of creating a sustainable low–carbon energy future, the commercial deployment of CCS is non-negotiable. The value proposition for CCS does exist, but it is complex and challenging to communicate ..." 
I finished the report feeling that the hurdles in front of carbon capture and storage becoming commercially viable were every bit as large as I had previously thought, if not larger. But there is some interesting work happening: a report in the December 2013 of Scientific American described some research in which carbon dioxide is injected into underground basalt formations, where minerals would interact with the carbon dioxide to turn the carbon into a solid--thus eliminating any risk it might leak out in the future.  The risk of adverse climate change scenarios from higher carbon emissions is substantial enough that no possible solutions, even partial solutions, should be neglected.