Getting on with it: What’s holding back CCS?

A nighttime view of Grangemouth: A light-filled skyline of oil refineries and similar buildings

A recent panel discussion in Glasgow brought together representives from some of the firms helping to build a carbon capture and storage (CCS) industry in the UK.1 The sector is making progress with the storage and transport of captured CO2, but there are many obstacles to be overcome.

It’s become a familiar refrain: Net Zero will be unachievable without widespread deployment of engineered GHG removals. CCS is a frontrunner in this endeavour, relying on already-proven technology and with the possibility of being deployed relatively quickly.

At a panel discussion at the All Energy conference in Glasgow in May, representatives from stakeholders in this fledgling sector all seemed to agree that it’s not happening fast enough, and offered thoughts on how to overcome some of the bottlenecks.

The opportunity seems to be huge, for an industry whose size will have to rival that of the fossil fuel industry, if it is to achieve its aims,2 and the UK has been pursuing it aggressively. “We’ve never seen such ambition in public policy,” commented panellist Dr William Joyce of Innovate UK. The UK government has plans to curb 20-30 million tonnes of CO2 per year through CCS by 2030, with £20 billion being made available to fund a series of projects through its cluster sequencing programme.

We need to grow, he suggested, and there seems ample opportunity to do so.

Europe’s storehouse?
An important piece of the puzzle is storage: ensuring that captured carbon can be safely and sustainably sequestered over the long term. Towards that end, the UK is “fantastically positioned”, he said, with significant potential on its continental shelf, in geological structures such as depleted oil and gas fields, and saline aquifers under the sea bed. It amounts to 78 Gtonnes of potential storage, a capacity sufficient to store all of the UK’s captured carbon, as well as all that captured by the remaining EU countries combined. “The UK could become a global leader,” he said.

Scotland especially is perfectly placed for CCS, with its existing oil and gas workforce, and infrastructure, which can be repurposed for CO2 storage. The North Sea alone could store around 10-11M tonnes per year. Scotland also has the deep shipping ports and infrastructure needed to become a transport hub, and a storage destination for other countries’ carbon capture efforts.

A frontrunner in the carbon storage effort worldwide is Norway’s Northern Lights project, jointly owned by TotalEnergies, Equinor and Shell. It is scheduled to come on stream this year, with the ability to handle up to 1.5 million tons of CO2 per year.

Storage is now beginning to happen in the UK too, with five of the projects in the northwest of England’s industrial cluster – home of the Hynet project, which integrates hydrogen production and CCUS – having been selected to begin flowing millions of tonnes of CO2 into depleted gas fields in Liverpool Bay.

There are “a lot of thermodynamic challenges” when it comes to injection of the material into a CO2 well. The situation is sometimes compared to a deodorant can, in so far as the temperature and pressure in the storage well must be sufficiently controlled to maintain the CO2 in a supercritical state, where it has the properties of both a liquid and a gas.

The technology exists, said Joyce, but we are now attempting to deliver it “at huge scale”, which is not-so-trivial.

Other projects have announced dates to begin storage. Humber Zero, which will see carbon capture technology being applied to gas-fired electricity generators and a fluidized catalytic cracker in the Humber refinery, recently said it is on target to inject the first CO2 into storage by late 2026, in locations under the North Sea bed.

Pierre Girard, Director of New Energy with Neptune Energy said that developing the storage infrastructure is “very costly” and “needs a lot of commitment”. Work is also needed to develop “a shared framework for the management of liabilities”.

The UK has started on a trajectory of a very sophisticated business model which was “great”, he said, especially in light of previous, unsuccessful attempts to get CO2 storage off the ground.

One important framework to work within is the London Protocol, which outlines strict monitoring and safety measures for the transnational export and storage of CO2, but this was, in effect, “a very small barrier”.

One barrier at the moment is the incompatibility between the respective Emissions Trading Schemes of the EU and UK, but this will be “not hard to solve”. Carbon storage still needs a lot of subsidies so trading schemes need to be aligned.

Transporting the stuff
Closely related to the storage issue is transport: getting the captured CO2 to where it will be stored, and in a way that minimizes cost and emissions intensity.

A report from the Oxford Institute for Energy Studies (OIES), published in May, attempts to evaluate the business case for carbon capture and storage in the UK’s energy-from-waste sector, and includes an analysis of transportation options. In appraising the options – pipeline, rail, ship or truck – it concludes that pipeline transportation provides the lowest cost and emissions for the UK EfW sector. However, the opportunity to deploy pipelines is limited by things like the time needed for regulatory and land approvals, and construction.

The report notes that, “for sites where all transport modes are viable, the typical cost merit order is pipeline < ship < rail < truck.”

A crucial milestone has recently been reported with work that provides pipelines to connect Teesside-based carbon capture projects to offshore storage, in work completed by Costain (see box, “Pipeline pioneers”, at the end of this article).

Repurposing pipelines
When it comes to repurposing pipeline infrastructure for CO2, issues can arise in relation to flow lengths. For example, pressure drops over long distances can introduce the need for recompression along its length – an additional cost and complexity not present when piping natural gas.

CO2 is also “not nice and squashy like natural gas”, as Jonathan Minnitt of Aker Solutions noted during the panel discussion, and the effort to repurpose natural gas infrastructure for sending CO2 by pipeline can present potential difficulties, a point explored in the recent Scotland Net Zero Roadmap.

Corrosion of pipelines is a problem that is “significant”, he said – and this is another issue with CO2 (but not with natural gas). One panellist said they had considered non-weld solutions like plastic pipelines, which would seem to introduce advantages like corrosion resistance, and less reliance on welding.

The UK government launched a call for evidence on 7 May, looking for “innovative new options for transporting CO2 on top of the existing network of pipelines”.

“Millions of tonnes of captured CO2 could be transported via road, rail, barge or ship, revolutionising the way it reaches offshore storage sites, helping more businesses cut emissions,” says the document.

Minnitt of Aker Solutions cited recent projects that have exploited opportunities to co-locate different elements of this value chain in close geographic proximity, minimising the need for pipelines.

Environmental approvals
Pipelines or infrastructure will also mean boxes to tick when it comes to proving the acceptable environmental impact of projects, ironically, an obstacle over which some developers have stumbled. Pierre Girard of Neptune Energy said a lot of regulators wanted to see a full picture of the emissions associated with a site, including construction, operations, commissioning and so on. The recent delay of a project to store carbon in the empty gas fields at Porthos in Rotterdam – because of NOx emissions associated with the proposed construction work – was, he said, “really sad”.

A demand for detail is also apparent with Monitoring, Measurement, and Verification (MMV), an important section in project permit applications for carbon storage.

MMV was another part of the value chain that panellists suggested presented opportunities for the UK, requiring expertise in thiings like monitoring and fibre optics.

A carbon capture facility at Peterhead power station in Aberdeenshire will capture more than 90 percent of all carbon burned, says SSE Thermal.

Tweaking performance
The performance of CCS is an area where panellists reported progress. The environmental benefits that can be attributed to projects are also tied in with making progress here. For example, a new gas-fired power plant at Peterhead will be equipped with carbon capture technology, a collaborative effort between SSE and Equinor, which the firms say will capture more than 90 percent of all the carbon burned, a capability that would make it a frontrunner in this respect.

Doga Satir, a process engineer with SSE Thermal offered an overview of aspects of the carbon capture portion of the plant, which will use a solvent-based system. The group has benefitted from Innovate UK funding, which has assisted with research to maximize the CO2 capture upon start-up. A project called FOCUSS (Flexibly Operated Capture using Solvent Storage) has looked at start-up and shutdown behaviour, and optimising the use of solvent, including “how to use some of the solvent that hasn’t captured CO2”, said Satir.

Working together to lower costs
Co-operation was another big talking point, and the need to link different parts of the value chain. Minnitt made the analogy with mobile phone chargers. How long did it take us to get interchangeable USB cables? Ages. Key to the timely uptake of CCS going forward is to standardise on different modular ingredients of the infrastructure, so that entry costs can be lowered. One notable initiative is LINCCS (Linking the CCS value chain), which aims to bring together industrial actors working on the Norwegian Continental Shelf, to increase the pace of CCS uptake.

A report published in May by the Centre for Energy Policy at the University of Strathclyde seemed to find that the introduction of carbon capture in the Scottish chemical industries could have negative implications for the competitiveness of the industry, but these ill-effects could be limited if there is “a UK-wider coordinated approach to the implementation of carbon capture”.

The research also attempted to quantify the negative impact accruing from the choice of technology, specifically in relation to the decision to use either pre-combustion or post-combustion carbon capture, with the former’s greater requirement for equipment and capital translating into a higher price impact of 3.12% (compared to 2.19% if post-combustion carbon capture was introduced).

The panel discussion in May seemed to highlight the vast opportunity for the UK to be a prime carbon storage location for the rest of Europe.

During the discussion, Girard said it would be a shame if the UK was to be deprived of some of the opportunities because of barriers, such as those affecting the cross-border transfer of CO2, or because of Brexit, or culture or protectionism. “We should all work together,” he said.

[ SIDE PANEL: Pipeline pioneers ]

A key milestone was reached in February in the East Coast Cluster – the collective decarbonization effort underway covering Teesside and the Humber – with the completion of the front-end engineering design (FEED) stage.

The work was undertaken by engineering contractor Costain. It included provision of gas supply pipework and a high voltage power network. When completed, the site’s c.12km of 22” pipeline will have an initial capacity to transport around 4m tonnes of CO2 per annum to be securely stored under the North Sea.

Laura Hughes, energy sector director at Costain, said the CO2 gathering network “is the first in the world to be a wholly above-ground network.” She added: “This presented interesting design and engineering challenges when considering the properties of CO2 and its ability to liquify at certain temperatures and pressures.”

“However, extensive flow assurance simulations and data modelling has given us a better understanding of the dynamics of CO2 and its behaviours to successfully complete the design for a safe, re silient and efficient network.”

The Costain FEED team, operating out of Teesside and Manchester with partners px Group, used a variety of techniques and technologies to design the routing for the carbon capture network. Key to the success was creating a new geographic information system (GIS) to act as a single source to capture asset information and data from a variety of sources and stakeholders. This included extensive use of laser scanning, topographical information, and ground investigations in order to document, for the first-time, the above-and-below ground assets at the site location.
“The digital footprint that has been generated for the area is pioneering,” said Hughes.

[1] “Industry Decarbonisation 3: Scotland’s industrial transformation: local and global opportunities for hydrogen and CCUS”, In association with NECCUS. Panel session at All Energy, 16th May, 11am-12.30pm.
[2] Smith, Wake. Pandora’s Toolbox: The Hopes and Hazards of Climate Intervention. Cambridge University Press; New edition (24 Mar. 2022).