The title may sound slightly frivolous – with visions of elephants jumping hurdles or being serenaded in gondolas as they drift under the Bridge of Sighs – but the subject matter is really very serious. It is the future of CO₂ storage that will determine the degree of success of CCS in Europe. I use the term 'degree of success' as opposed to 'success or failure' because we simply cannot afford to fail with CCS. It is not an option. Several other factors could play a role, but none more important than storage. Unfortunately, we have already made big mistakes which are now hampering our progress.

Storage of carbon dioxide had been going on at Sleipner (Norway) for over 10 years and a very small number of EU Member States had started to think about CCS in a relatively low-key way before CCS finally made its serious political debut in Europe. This was in 2007/2008 when energy and climate policies were top of the political agenda. Europe clearly needed to continue its use of coal for economic and supply security reasons, but its emissions remained a major problem.

Emphasis was immediately placed on the technology for capturing the gas. It was clearly in the interest of the equipment suppliers to bring capture to the fore and the utilities, whose expertise was in operating large industrial plants, were comfortable with this emphasis. Only a limited number of them had experience in transporting gases and even fewer had experience in deep geology (especially offshore). It was generally assumed that transport would not be a major issue and that pumping the gas underground would not present any particular problems. Only those companies or organisations that had already experienced some local resistance to exploratory work sounded the warning bells, but they went unheeded in the enthusiasm for the technology and its unquestioned benefits from the point of view of climate change. The expectations were that the carbon price under the Emission Trading System (ETS) would rise quite quickly and, as a result, encourage demonstration and fund early deployment. We were somewhat over-optimistic!

In 2006, the electricity producer EoN announced that it would be building a new coal-fired power plant at its Kingsnorth site in Kent (UK) as replacement for units at the site. In 2008 it announced that part of the new capacity would be equipped with CCS and would enter the UK's CCS competition. However, by October 2009, the company had announced that the project would be delayed, and one year later announced its cancellation. While the cancellation was for commercial reasons – the company was and still is supportive of CCS and are expected to take a final investment decision (FID) soon on the ROAD CCS demonstration project in the Netherlands – delays in the CCS project could have proved important. A retrospective view on the project might have come to the conclusion that it should have been 'storage-led'. This is a realisation that several other projects are now arriving at. While capture equipment and pipes can, to a greater or lesser extent, be bought 'off the shelf', the same is unfortunately not true for storage capacity nor for a storage site.

It is with some dismay that companies have started to realise that it is likely, in many cases, to take seven to 10 years from preliminary identification of a potential storage site to it receiving its storage permit, especially if you are looking at virtually unexplored saline aquifers in the North Sea. It is of particular concern if you are already less than five years away from a major funding deadline by which you should be demonstrating the full CCS value chain! Who will be ready and willing to capture a million tonnes of carbon dioxide a year if they have nowhere to put it? In fact, how many companies can afford to take an investment risk in the technology to add to their plants before they have at least some form of assurances about storage? It would probably not be an attractive option even in times of strong economic growth. At the present time in Europe it is something that could only be done with strong political support, mainly in the form of major grant funding.

Therefore it is hardly surprising that the need for storage is seen as one of the hurdles for the demonstration of CCS. It is, of course, not the only one. There are regulatory and financial hurdles, the need for infrastructure for transporting CO₂ and a noticeable lack, at this moment in time, of political support and public acceptance in European countries. This is where the elephants make their appearance! In April this year I participated in a BP-sponsored symposium in Brussels on 'Getting Carbon Capture and Storage Technologies to Market'. Towards the end of the meeting, participants were asked to identify their 'elephant in the room' as far as CCS was concerned – meaning, in this case, what had the greatest potential to negatively impact the progress of CCS. All the usual suspects were mentioned, though two topics stood out: public acceptance and the lack of storage. Every geologist in the meeting identified the need for storage. This was not because geologists do not believe that there is inadequate potential for storage in Europe. In fact the opposite is the case. Europe has tremendous potential for storing CO₂ both onshore and offshore, but at the moment it is almost all still potential. A great deal of effort needs to be done to confirm that this is useable. This takes time and money, especially working in the difficult environment of the North Sea. A massive exploration effort, comparable to that required to support the oil and gas industry, could well be needed.

In addition, the other big 'elephant', public acceptance, is most commonly related to storage, in particular the safety or perceived lack of safety of geological storage. Yet another member of the herd was political acceptance, which is closely linked to public acceptance and hence to storage. So the lack of proven storage is a major hurdle, or a massive elephant in the room to the demonstration of CCS.

So where do gondolas fit into this? The answer, not surprisingly, is in Venice! This is a reference to the CO₂ GeoNet and CGS Europe meetings that were held on the Venetian island of San Servalo in April 2012. This was the seventh annual 'open forum' of GeoNet and gave a comprehensive review of the research on storage in Europe, including many encouraging results. The large majority of the presentations were of R&D activities supported by the European Commission's Framework R&D programmes. Many of the presentations were excellent and reported on good progress.

A good example was the report on the SiteChar project and, in particular of the permitting 'dry runs' that were being carried out for the offshore Moray (UK) site and the onshore Vedsted site (Denmark). This work has strong parallels with the Global CCS Institute-sponsored regulatory toolkit for CCS. The project also has a number of other interesting work packages, such as the studies on public awareness for a UK offshore site and a Polish onshore one. Other projects that attracted considerable attention included:

• CO2Remove – a project that is just finishing (finalisation of report) after 5 years of work (monitoring and verification of CO₂ geological storage);
• MUSTANG – a large-scale project for developing methodologies for quantifying saline aquifers for storage;
• RISC – impacts and safety of CO₂ storage, basically looking at leak detection for onshore and offshore sites; and
• ECO2 – detecting and monitoring sub-seabed CO₂ emissions.

The CGS knowledge sharing workshop included some excellent presentations on national storage activities including identification of sites for the Belchatow (Poland) and Getica (Romania) CCS Demonstration Projects. All the presentations from both meetings are available from the CO2GeoNet site.

While the 'gondola meetings' did not present all the answers to the hurdles or elephants question, they clearly indicate we are well advanced on providing some of them. But the full characterisation of likely storage sites is still going to be the controlling influence over how soon CCS can be demonstrated and deployed. This will still take considerable efforts, money and, of course, time – much more than we have presently available!

Source: GCCSI blog, Derek Taylor, 27 June 2012