One emerging technology that has a major role to play in reducing greenhouse gas emissions to mitigate global climate change is carbon capture and storage 1 (carbon capture and storage, CCS), or, more broadly, carbon capture, utilization and storage (CCUS). According to recent assessments by the Intergovernmental Panel on Climate Change (IPCC) and the International Energy Agency (IEA), achieving the climate goals set by the 2015 Paris Agreement is virtually impossible without extensive use of CCS/CCUS technologies.
In 2021, the IEA published its report Zero Carbon by 2050: A Roadmap for Global Energy, which for the first time detailed and calculated a pathway to full decarbonisation of the global energy industry by 2050 — an absolute prerequisite for keeping global average surface temperature rise within 1.5 °C of pre-industrial levels. Among other things, the IEA calculates that this will require capturing up to 1.7 billion tonnes of carbon dioxide in 2030 and up to 7.6 billion tonnes in 2050 (see Figure 1). Some 95% of the captured carbon dioxide will be buried in geological formations and 5% will be used to produce synthetic fuels, mainly for civil aviation.
Figure 1. Development of carbon dioxide capture and storage capacity in a net-zero (1.5 °C) scenario
Infographics: IEA, 2021
CCUS technologies are not only expected to be used in the energy sector to capture carbon dioxide from coal, natural gas and biofuels in power stations, but also in the most carbon-intensive industries, such as cement and hydrogen production, as well as for direct removal of carbon dioxide from the atmosphere. Specifically, the contribution from biomass-generated energy with carbon capture and storage (BECCS) production is projected to be 255 million tonnes of CO2 captured per year by 2030, while that from direct air carbon capture and storage (DACCS) is projected to be 90 million tonnes per year, rising to 1,380 million tonnes and 985 million tonnes per year respectively by 2050.
According to the report by the Global CCS Institute, the number of carbon capture and storage projects under development rose to a record high in 2022. As of September, there were a total of 196 such projects worldwide with a total capacity of around 244 million tonnes, including 30 active projects with a combined capacity of 42.5 million tonnes (see Figure 2).
Figure 2. CCS projects under development worldwide by capacity, million tonnes of СО2 per year
Infographics: Global CCS Institute, 2022
Since September 2021, the capacity of CCS projects under development worldwide has increased by 44%. The largest number of new projects during this period came from the USA (34 projects), followed by Canada (19), the UK (13), Norway (eight), Australia, the Netherlands and Iceland (six new projects each).
Many countries have legislative frameworks and support systems for CCUS projects. For example, the EU has a directive setting rules for geological storage of CO2 (Directive 2009/31/EC on the Geological Storage of Carbon Dioxide), and the European Emissions Trading Scheme (EU ETS) allows emitters to keep (not redeem) emission permits (EUA) if the appropriate amount of CO2 has been captured and sent for storage. CCUS projects can also receive direct public funding through mechanisms such as the Connecting Europe Facility, Innovation Fund, Horizon Europe and the Recovery and Resilient Facility.
In the US, existing CCS support measures under the Infrastructure Investment and Jobs Act and Section 45Q of the Internal Revenue Code were supplemented in 2022 with new measures under the Inflation Reduction Act.
In Canada, the already strong incentives and support measures for CCS have been further enhanced in 2022 with the introduction of a federal investment tax credit for CCS projects, similar to what is done in the US.
According to the Global CCS Institute, favourable policies including high CO2 prices, tax incentives and direct subsidies have stimulated investment in carbon capture projects.
Overall, however, the level and rate of diffusion of CCS projects globally has remained very modest. The technology is still at an early stage of development and there is no indication yet that it can take its rightful place in the decarbonisation of the global economy in line with the goals and objectives of the Paris Agreement, unless there is a technological breakthrough.
The report “A Practice Check: Why CCS does not play a role in Australia’s energy system” produced by the Energy Policy Centre at the University of Victoria, Australia, is illustrative in this respect. The purpose of the paper was fairly narrow: to assess the economics of Australian projects in which coal-based power generation would be complemented by carbon capture and storage technologies. Gas generation was not considered because there are as yet no examples of CCS applications in gas-fired power plants, either in Australia or elsewhere. The conclusions, however, were far-reaching.
In particular, it has been shown that it does not make economic sense to build new coal-fired power plants equipped with CCS because they are clearly inferior to solar and wind plants in terms of the cost of energy produced, even when the solar and wind plants are equipped with energy filling and storage systems. Adding CCS to a new coal-fired generator increases the cost (LCOE) of generated electricity to A$280—322 per MWh and to A$314—363 per MWh on lignite, whereas a reasonable electricity price to justify the cost of building a modern 100 MW wind farm with 50 MW of energy storage is only about A$45 per MWh.
In addition, it should be taken into account that the use of CCS technology does not mean reducing the carbon footprint of electricity to zero. According to a study published in Nature Energy in 2017, when considering the full life cycle of generation facilities, specific emissions from a coal-fired power plant equipped with CCS are 109 grams of CO2-eq per kWh, while a gas-fired power plant with CCS is 78 grams of CO2-eq per kWh, which is significantly higher than the specific emissions from nuclear and renewable energy generation.
Many critics point out that CCS technology, at least in its current form, does not solve the problem of reducing anthropogenic greenhouse gas emissions into the atmosphere, but is used mainly to prolong the life of fossil fuels (primarily coal, but also natural gas) by creating the illusion that modern fossil fuel-based energy technologies can supposedly be climate-friendly and can operate without greenhouse gas emissions into the atmosphere. Indirectly in favour of this version is the fact that the main initiators and investors of CCS projects today are large oil and gas companies, which use their lobbying capabilities and various measures of state support, including direct budget subsidies, which does not look quite appropriate against the background of problems faced by other “green” technologies.
Either way, CCS technologies are certainly not a panacea and should be used alongside other promising decarbonisation technologies, not instead of them. Technical requirements (standards) and other conditions should be developed for them, which will define the role and place of these technologies in the overall series of measures to decarbonise the economy in order to achieve an early balance between anthropogenic emissions into the atmosphere and removal of greenhouse gases from the atmosphere and mitigate climate change on this basis in accordance with the goals and objectives of the Paris Agreement.
1 In reality, it is not carbon as such, but carbon dioxide, or carbon dioxide. In climate science, carbon dioxide emissions into the atmosphere and its content (concentration) in the atmosphere are often measured in terms of carbon. Hence, the tradition of using the short word “carbon” instead of the long word “carbon dioxide” or “carbon dioxide” has emerged and over time has taken root.
Cover photo: Schroptschop / iStock
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