By Hon Chung Lau1 and Seeram Ramakrishna2
1Department of Civil and Environmental Engineering, National University of Singapore
2Department of Mechanical Engineering, National University of Singapore
One important fact often neglected in the discussion of energy transition is that to achieve net-zero, every nation needs to decarbonize not only its power sector but also its industry and transport sectors (Lau, 2021a, 2021b). Of these three sectors, the power sector is the easiest to decarbonize because renewable energies such as wind, solar photovoltaic (PV), and hydroelectricity have made significant contribution to power generation. Globally, about 26% of electricity is generated by renewable energies (Lau, 2021a). Currently, a newly built wind or solar PV power plant costs about the same as a fossil fuel power plant (Lau, 2021a). Consequently, it is likely that renewable power plants will replace fossil fuel power plants in the next two decades in countries which have substantial wind and solar energies. What about countries which do not have significant renewable energies such as Singapore, South Korea or Japan? How will they decarbonize their energy consumption sectors? For the power sector, one way is to switch from coal-fired to natural gas fired power plants. Doing so will reduce power plant emitted CO2 by almost one-half, as natural gas is the cleanest form of fossil fuel. One country that has achieved this is Singapore where over 95% of its electricity comes from natural gas fired power plants (Lau and Ramakrishna 2021a). Still, Singapore’s natural gas fired power plants produced 19 Mtpa CO2 in 2017 (Lau and Ramakrishna, 2021a). What can be done to decarbonize them? One way is to employ carbon capture and storage (CCS) technology to capture CO2 from large stationary sources and transport it to a suitable site for subsurface storage. Three types of subsurface reservoirs may be used for permanent CO2 storage: oil reservoirs, gas reservoirs, or saline aquifers (Lau et al., 2021). Indeed, CCS can be used not only to decarbonize fossil fuel power plants but also other hard-to-decarbonize plants such as iron and steel mills and cement factories. Currently, CCS is the only technologically mature technology capable of removing CO2 at a scale of million tonnes per year (Lau et al., 2021). Other technologies such as carbon capture and utilization (CCU) are still in research stage and are yet to utilize CO2 in a scale of tens of million tonnes per year.
For the transport sector, electric vehicles and hydrogen fuel cell vehicles will likely replace internal-combustion-engine vehicles in the next two to three decades. The practical consequence of this is to replace mobile CO2 sources with stationary sources such as power and hydrogen plants. If these plants are fueled by fossil fuels, CCS can also be used to mitigate the emitted CO2.
The world is literally running out of time to achieve net-zero by 2050 to limit the earth’s atmospheric temperature rise to 2oC above pre-industrial times. Achieving net-zero will require nations to use all available technologies such as renewable energies, CCS, hydrogen, and the adoption of a circular economy (Lau et al., 2021). Waiting for sufficient renewable energies to become available or CCU technologies to mature will not meet the timetable of net-zero by 2050, especially for those countries that lack significant renewable energy resources. It is high time to get serious about decarbonization by installing CCS on a large scale. One such effort is the Northern Lights Project recently sanctioned by the Norwegian government (Lau et al., 2021). The plan is capture 0.8 Mtpa of CO2 from two plants in southeast Norway, ship it by tankers the west coast of Norway where it will be sequestered permanently in an offshore saline aquifer by one subsea well. The project will come on stream in 2024. There are plans to sequester up 5 Mtpa CO2 by receiving CO2 from other European countries.
ASEAN can emulate the Northern Lights project, and launch a first-of-a-kind cross-border CCS project “Southern Lights” beginning with one Mtpa of industrial CO2 from Singapore transported and stored away in a subsurface reservoir in the region (Lau and Ramakrishna, 2021a, 2021b). Such a demonstration project will provide necessary experience and engineering expertise to leverage on by other countries in the region. This will create a regional CCS corridor where the cost of CO2 transport and storage can be minimized by economy of scale, government-to-government cooperation, and international financing. Our estimates show that there is enough storage space in saline aquifers and depleted oil and gas fields within ASEAN to store more than 100 Gt of industrial CO2 (Lau and Ramakrishna, 2021a).
Implementing a cross-border ASEAN CCS project will require much work and effort from various stakeholders (Lau et al., 2021). It is easy for us to take a wait-and-see attitude toward decarbonization. Unfortunately, meeting the target of net-zero by 2050 requires bold actions from all stakeholders. Will ASEAN countries rise to this challenge of decarbonization? Afterall, decarbonization is the biggest engineering challenge faced by humanity. Big challenges require bold actions.
Lau, H. C. 2021a. The Color of Energy: The Competition to be the Energy of the Future, presented at the International Petroleum Technology Conference, 23 March to 1 April, paper IPTC-21348-MS.
Lau, H. C., 2021b. The Role of Fossil Fuels in a Hydrogen Economy, presented at the International Conference, 23 March to 1 April, paper IPTC-21162-MS.
Lau, H. C. and Ramakrishna, S. 2021a. A Roadmap for Decarbonization of Singapore and Its Implications for ASEAN: Opportunities for 4IR Technologies and Sustainable Development, United Nations ESCAP, Asia-Pacific Tech Monitor, Apr-Jun issue.
Lau, H. C. and Ramakrishna, S. 2021b. Why Carbon Capture Should be in Singapore’s Green Toolkit, The Straits Times, 3 June, https://www.straitstimes.com/opinion/why-carbon-capture -should-be-in-singapores-green-toolkit.
Lau, H. C. Ramakrishna, S., Zhang, K. and Radhamani, A. V., 2021. The Role of Carbon Capture and Storage in the Energy Transition, Energy & Fuels, 35, 7364-7386.