The role of CCS in reducing emissions remains unclear [GasTransitions]

A group of engineers and geologists issued a statement in January saying that carbon capture and storage is “vital to meeting climate goals.” Their initiative came in response to a report from Friends of the Earth Scotland, prepared by Samira Garcia Freites and Christopher Jones of the Tyndall Manchester Climate Change Research unit, which came out on 8 January. The Tyndall report calls on the UK government not to invest in CCS, which it says is “a distraction from the rapid growth of renewable energy and energy efficiency required”.

According to the scientists, led by professor Stuart Haszeldine of Edinburgh University, the resistance to CCS by environmental groups is misguided. “Carbon capture and storage is going to be the only effective way we have in the short term to prevent our steel industry, cement manufacture and many other processes from continuing to pour emissions into the atmosphere,” he said.

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Key role

The Tyndall report shows that most global climate scenarios rely heavily on CCS to meet climate targets. The IPCC 1.5°C Global Warming Report, for example, assumes between 384 GT and 1,218 GT of CO₂ captured and stored by century-end cumulatively. The IEA’s Sustainable Development Scenario envisages 2.78 GT of CO₂ captured and stored by 2050 on an annual basis, equally split between power and industry. This amounts to 9% of the energy-related CO₂ emission-reductions required.

The European Commission has also accorded “a key role of CCS deployment to meet the EU’s long-term emissions reduction target by 2050,” notes Tyndall. “The Commission expects CCS to become one of the few technology options to cut direct emissions at scale from industrial processes and serve as a low-carbon technology when combined with fossil fuel-based generation to provide flexibility to energy systems, with increasing variable renewable sources.”

Nevertheless, as Tyndall notes, the Commission has also indicated that “the role of CCS has diminished with the faster deployment of renewable energy and other technologies to reduce emissions from industrial processes.” In its hydrogen strategy, the Commission emphasises electrolysis derived “green” hydrogen rather than “blue” hydrogen based on CCS.

However, to date, the scale of deployment of CCS is significantly less than proponents have predicted, notes Tyndall, with only 26 CCS plants in operation globally with a total capacity of 39 MT of CO₂ per year. This is about 0.1% of global emissions from fossil fuels. Moreover, 81% of the carbon captured to date has been used in enhanced oil recovery projects. In the UK, “there is no operational CCS capacity at all.”

Game not over

These observations are not new of course. In particular, the application of CCS to fossil-based power plants has been disappointing so far. Yet according to the pro-CCS scientists the game is not over yet for CCS. They note that in other industries, such as steel, chemicals and cement, renewable alternatives are not as easily found as in the power sector. “When CCS was first touted it was seen as a way of cleaning up electricity generated by fossil fuels,” said Haszeldine. “But now it is clear it can play a key role in cleaning up other industries.”

There are more signs that CCS has not been written off yet by the world. In a paper in Nature published on 4 January, Yi-Ming Wei and a group of Chinese scientists propose a “straightforward global layout of carbon capture, utilization and storage (CCUS)” which they say “is imperative for limiting global warming well below 2 °C.”

The Chinese scientists lay out a “cost-effective strategy for matching carbon sources and sinks on a global scale. Results show 3,093 carbon clusters and 432 sinks in 85 countries and regions are selected to achieve 92 GtCO₂ mitigation by CCUS, 64% of which will be sequestered into sedimentary basins for aquifer storage and 36% will be used for CO₂-EOR (enhanced oil recovery).” The total cost, they say, would be “0.12% of global cumulative gross domestic product. Of countries with CO₂-EOR, 75% will turn profitable at an oil price over US$100 per barrel. These findings indicate our proposed layout is economically feasible. However, its implementation requires global collaboration on financial and technological transfer.”

That’s theory, but the Chinese Environment Ministry reiterated recently that China will promote large-scale carbon capture projects as part of its contribution to climate change mitigation, according to a report from Reuters on 13 January. In “new policy guidelines”, the Ministry said “it would promote the construction of large-scale carbon capture, utilisation and storage demonstration projects. China has several carbon capture projects in operation, but none has been economically viable.”

On track

In the Netherlands, Porthos, a major CCS project undertaken by Air Liquide, Air Products, ExxonMobil and Shell, is “on track”, the consortium said in a press release. The aim of Porthos is to capture 2.5 million tons annually from 2024 onwards from industries in Rotterdam and bury it in empty gas fields in the North Sea. The EU has committed €102 million to the project, for which an FID is expected in 2022. A consortium of EBN, Gasunie and the Port of Rotterdam are building the pipes and compressor station for the project.

According to the consortium, the cost per tonne of the project will be about half of that of alternative CO₂ emission reduction schemes in the Netherlands.

Less positive news for CCS from Australia, where the Morrison government fervently believes in CCS and has identified it as a priority technology in its Technology Investment Roadmap. According to an analysis undertaken by associate professor Bruce Mountain of the Victoria Energy Policy Centre at Victoria University, carbon capture and storage technology added to a new coal-fired generator could raise the levelised cost of electricity by between $90 and $125 per MWh. That would make coal power equipped with CCS up to six times more expensive than wind and solar, combined with energy storage, he said.

Mountain found that CCS more than doubles the capital outlay for coal-fired power stations, and costs even more for gas generators than coal generators. “Making accurate cost estimates is not easy, as there are only two commercial-scale electricity generation projects using capture and storage in the world,” the researcher noted. “One of those has already been mothballed and the second operates far below its design capacity. There are other examples of carbon capture and storage in the oil extraction industry, but these are not dealing with emissions from electricity generation.”

Gorgon

Mountain’s findings apply to power plants, but Chevron’s huge CCS project at the Gorgon LNG facility off the coast of Western Australia is also running into problems, reports Michael Mazengarb on the website of Reneweconomy.com.

He cites documents obtained by outlet Boiling Cold through a freedom of information request which show that the Gorgon carbon capture and storage project, on which Chevron has already spent more than $3 billion, has encountered a number of issues since it commenced the storage of carbon dioxide in 2019, which seriously hamper its functioning. At the giant Gorgon site, Chevron is attempting to store up to 4 million tonnes of CO₂, which is as much as 80% of the project’s direct greenhouse gas emissions. Gorgon has a production capacity of up to 15.6 million metric tons per year of LNG.

To facilitate the storage of the carbon dioxide, writes Mazengarb, Chevron must first remove water from the undersea deposit known as the ‘Dupuy Formation’. However, the company has discovered that a “significant volume of sand” is preventing this water from being extracted. “It is now thought likely the loss of injectivity in the water injection wells is primarily due to the presence of significant volumes of sand being produced from the Dupuy Formation,” Chevron said in a project report.

Until the issue is resolved, Chevron’s ability to store carbon dioxide in the undersea deposit is diminished, notes Mazengarb. The CCS project was already running three years behind schedule when it became operational in 2019.

Western Australia’s Department of Mines, Industry Regulation & Safety (DMIRS) has granted Chevron a conditional “consent to operate” without the CCS system online. Under the licensing approvals for Gorgon, Chevron is required to sequester at least 80% of the CO₂ emissions released from the reservoirs that feed the Gorgon LNG plant over a five-year period. The company may now be required to pay offsets for failing to reach that target. Chevron has said in a statement that the problems at the CCS facility will not hinder its LNG production.

Taken together, the news on CCS makes it difficult to predict whether this technology will be able to deliver on its promises. As the Tyndall report pointedly observes: “the role fossil-based CCS can and should have in energy system decarbonisation is unclear.” For the gas industry, this is surely a major headache.