Science & Technology

Most carbon capture & utilisation technologies may be counterproductive: Study

CCU techs might divert attention from more effective emission reduction options

By Rohini Krishnamurthy
Published: Wednesday 23 February 2022
Most carbon capture & utilisation technologies may be counterproductive: Study Photo: Climate Central

Most carbon capture and utilisation (CCU) technologies, which suck carbon dioxide (CO2) from the atmosphere and convert it into fuel or other valuable products, might fail to help the world reach Net Zero emissions by 2050, according to a new study.

A majority of these systems are energy intensive and the resultant product can also release CO2 into the atmosphere, the lead author Kiane de Kleijne, a climate researcher at Radboud University, told Down To Earth (DTE).

Countries should narrow down on the handful of technologies that show more promise and channel investment in them, the researchers advised. Solutions that lock up carbon dioxide permanently and those that don’t release emissions during the CCU process, for instance, could potentially help, the study published in One Earth journal February 5, 2022 showed. 

CCU is considered an important tool to help countries halve their emissions by 2030 and reach net-zero by 2050. These goals are crucial to meet the Paris Agreement targets for restricting global warming to 2 degrees Celsius (°C), and preferable to 1.5°C, over pre-industrial levels.

Boon or bane? 

CO2 captured using CCU technologies are converted into fuel (methane and methanol), refrigerants and building materials. The captured gas is used directly in fire extinguishers, pharma, food and beverage industries as well as the agricultural sector. 

Replacing a conventional fuel with a synthetic fuel like methanol produced via CCU is likely to be a successful mitigation strategy only if clean energy is used to capture CO2 and convert it into synthetic fuel, said Varun Agarwal, senior project associate at the think-tank World Resources Institute. He was not involved in the study.

“This raises the question: Can this clean energy not be used more easily and efficiently to directly replace the use of conventional fuel?” he added. 

The researchers warned that most CCU techs might divert attention from more effective emission reduction options like carbon capture and permanent storage and reducing consumption. 

The researchers assessed 74 CCU technologies on two grounds: Emissions during the entire process and technology maturity level to support the conversion. Of the 74 technologies, only eight could potentially halve emissions by 2030 and four could help reach net zero emissions by 2050.

As of 2021, 27 carbon capture, utilisation and storage facilities are operating worldwide, and five others are under construction. Many are in the research and development phase, with 67 in the advanced stage and seven in the early stage. 

Typically, a technology takes 20-30 years to progress from the research and development stage to being available in the market.

The authors of the report rated CCU on their technology readiness level (TRL) – ranging from the basic concept (TRL 1) to successful, real-life operation (TRL 9). For a CCU technology to be ready and make a difference on the ground in 2030, it must have reached at least TRL 6 by 2020, according to the study.

Using CO2  to improve crop yields in agricultural greenhouses and enhanced oil recovery are two examples of mature CCU technologies, according to the study

Promising technologies

Taking stock of the current CCU technologies in meeting the Paris goals can help nations redirect funding to technologies that are more likely to reduce emissions drastically, Kleijne said.

CCU technologies that capture carbon dioxide from biogenic sources such as plants and soil to boost crop growth in a greenhouse could work, the report showed. 

Combining CO2 with steel slag — an industrial byproduct of the steel manufacturing process — to make construction materials are compatible with the Paris Agreement goals, according to the study

Challenges for India

Keeping pace with the global developments to building CCU capacity, the Indian government announced that it would establish two CCU centres: The National Centre of Excellence in Carbon Capture and Utilization at IIT, Bombay and the National Centre in Carbon Capture and Utilization at Bengaluru’s Jawaharlal Nehru Centre for Advanced Scientific Research.

The new study is more about technology variants in general rather than the native challenges within any specific region, Ankur Malyan, programme associate at the think tank Council on Energy, Environment and Water (CEEW), told DTE.

The technology is attractive to industries that lack effective clean energy alternatives, especially carbon-intensive sectors that manufacture cement, iron and steel or chemicals, according to the International Energy Agency.

Replacing cement with carbonated slag construction blocks, for instance, shows promise, experts said.

“Countries like India would need more construction material in the future, and climate-compatible construction blocks could be a game-changer,” Malyan explained.

India has a long way to go. “The country is in a very early stage of adopting these nascent technologies,” Malyan pointed out.

The researchers consider the greenhouse gas emissions intensity of electricity in 2030 to be 0.17 kilogram CO2 per kilowatt-hour.

The value for India, however, is expected to be over three times at 0.537 Kg CO2/KWh in 2030, Agarwal said.

Over the next couple of years, India should invest in building and strengthening research and development work on CCU technologies.

Demonstrating their capabilities will increase stakeholders' confidence in the technology while also helping them understand its uncertainties, Malyan added.

CCU is already making inroads into India. For instance, Oil and Natural Gas Corporation signed a Memorandum of Understanding with Indian Oil Corporation Limited (IOCL) for enhanced oil recovery (EOR) by injecting CO2 captured from IOCL’s Koyali refinery, Gujarat.

But Agarwal said that EOR does not have much scope in India considering its small oil reserves. “A more promising bet for India, I think, is to sequester (capture) carbon dioxide in its forests by expanding and restoring its forest cover,” he told DTE.

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