(528b) Climate Action Tool (CAT): Philosophy and Case Studies

The pressing concern of climate change requires urgent attention, with rising carbon dioxide emissions from human activities being a major factor. The most common greenhouse gas, carbon dioxide, makes up around 65% of all greenhouse gas emissions. Carbon dioxide emissions have surged by around 90% since 1970, mostly due to industrial activities and the combustion of fossil fuels. So, it is crucial to monitor and mitigate the release of carbon dioxide into the atmosphere through various sectors.

To address this challenge effectively, a comprehensive and adaptable tool for assessing and strategizing carbon dioxide mitigation efforts is being developed. This tool aims to provide a robust approach that can be applied across different sectors and sub-sectors. By modelling sectors and sub-sectors using first principles, the tool offers a holistic view of emission sources. Any source related to CO₂ emission can be integrated as a model in the tool. At the core of this tool is a modular design that allows for customization and integration of sector-specific parameters and equations. This modular approach enables users to model emissions from any sector based on input and output data, with the flexibility to enhance the model with additional phenomenological or data-driven elements as needed.

Utilizing mass and energy conservation equations to control volumes within each sector and sub-sector, the tool measures carbon dioxide emissions concerning factors such as feed quality, energy sources, and process efficiency. This approach identifies the important parameters influencing emissions and offers a foundation to develop effective mitigation strategies at minimal investment. One key strength of this tool is its ability to offer policymakers and industry stakeholders actionable insights into emission reduction. The tool allows for the analysis of several low-carbon strategies by incorporating optimization approaches to reduce the cost and emissions of cross-sectoral systems. Broadly, it facilitates the generation of strategies that require minimal targeted investments, thereby leading to considerably major emission reductions. For instance, to meet certain emission reduction targets given by government in a country, this tool can suggest the best technically and economically viable decarbonization strategy, such as an optimal fuel-mix ratio, carbon capture and utilization (CCU) along with the best timing for installation, or a combination thereof.

In one of our studies using the tool, we interconnected different industrial sectors: cement, steel, power, and hydrogen, where the latter two industries meet the demand of the former two industries. Intending to minimize the total cost (CapEx and OpEx) and total CO₂ emissions, with limits on fuel availability and technological constraints, we created two scenarios to analyze with this tool: (i) Current Landscape, (ii) Transformative Path Forward. In the first scenario without additional capital investment, only fuel-mix was optimized within the existing infrastructure. This showed heavy reliance on fossil fuels across sectors, with substantial investments needed in each sector. For the second scenario, the tool suggested to focus on the electrification of steel industry, good energy-mix and installation of CCS plant in cement and power industries in 2^nd year and also in fossil-based hydrogen production unit in 4^th year. While comparing between cement and steel sector, the tool showed that cement sector needs more investment due to fossil-based energy mix and mandatory CCS for process emissions. Scenario-2 used 25% less coal and 65% less natural gas as compared to Scenario-1. A strategic energy mix, featuring electrification and CCS, played a key role in achieving projected impressive 83% reduction in CO₂ emissions. It is important to emphasize that achieving such significant reductions in emissions across various sectors required minimal investment, which would have been substantially higher if these sectors were analysed individually. These types of analyses can aid policymakers, and industry stakeholders by providing an estimate of the budgets required to build strategies for decarbonization. Similarly, many such scenarios pertaining to agriculture, manufacturing, and transport can be generated, studied and interesting insights can be obtained using this tool.

Recent literature has introduced various tools designed to support policymakers and stakeholders in reducing emissions. Wang et al. [1] developed a model that explores different decarbonization strategies within China's power sector, considering spatial and temporal dynamics. Li et al. [2] investigated how electrification could lower emissions from China's light-duty trucks. Tan et al. [3] introduced a model that facilitates collaboration between government and industry to address maritime emissions, with the government suggesting CO2 reduction methods and industries implementing feasible solutions with minimal financial burden and reduced penalties. This model emphasizes a subsidy-penalty mechanism to achieve optimal decarbonization outcomes. Matamala et al. [4] examined the role of carbon capture and storage (CCS) technologies, coupled with negative emission techniques like biomass, in Latin America's power sector. Hebada et al. [5] explored various paths towards achieving net-zero emissions in Brazil's iron and steel industries by 2050. Vernay et al. [6] created a model to assess the effects of energy transitions on energy community businesses. In contrast to these existing models and tools, this tool presents numerous unique advantages. While reported models in the literature may be confined to specific sectors or regions, the proposed tool with a user-friendly interface and customizable functionalities, is applicable across various sectors and regions. Moreover, its basis in first principles ensures robustness and reliability. This feature not only enhances usability but also facilitates well-informed decision-making for policymakers and industry stakeholders.

Thus, the development of this comprehensive tool offers a versatile and reliable solution for addressing carbon dioxide emissions across different sectors and sub-sectors worldwide. Its adaptable design, rooted in fundamental principles, representing a significant leap forward in environmental management, delivers practical insights for policymakers and industry stakeholders to devise effective mitigation strategies, towards achieving emission reduction targets and fostering a sustainable, low-carbon economy, thereby contributing to the global endeavor to combat climate change.

References

[1] Y. Wang, Z. Zhao, W. Wang, D. Streimikiene, T. Balezentis, Interplay of multiple factors behind decarbonization of thermal electricity generation: A novel decomposition model, Technological Forecasting and Social Change. 189 (2023). https://doi.org/10.1016/j.techfore.2023.122368.

[2] J. Li, L. Wang, C. Ji, H. Liu, L. Lu, T. Zhang, M. Zhao, S. Xu, Assessing the decarbonization potential of China's light-duty truck fleet by electrification, Energy Reports. 9 (2023) 212–225. https://doi.org/10.1016/j.egyr.2023.03.018.

[3] R.R. Tan, I.H. V. Gue, J.F.D. Tapia, K.B. Aviso, Bilevel optimization model for maritime emissions reduction, Journal of Cleaner Production. 398 (2023). https://doi.org/10.1016/j.jclepro.2023.136589.

[4] Y. Matamala, F. Flores, A. Arriet, Z. Khan, F. Feijoo, Probabilistic feasibility assessment of sequestration reliance for climate targets, energy. 272 (2023) 127160. https://doi.org/10.1016/j.energy.2023.127160.

[5] O. Hebeda, B.S. Guimarães, G. Cretton-Souza, E.L. La Rovere, A.O. Pereira, Pathways for deep decarbonization of the Brazilian iron and steel industry, Journal of Cleaner Production. 401 (2023) 136675. https://doi.org/10.1016/j.jclepro.2023.136675.

[6] A.L. Vernay, C. Sebi, F. Arroyo, Energy community business models and their impact on the energy transition: Lessons learnt from France, Energy Policy. 175 (2023). https://doi.org/10.1016/j.enpol.2023.113473.