Graduate School of Carbon Neutrality

Abstract Ammonia is considered a promising energy source for achieving carbon neutrality because it is carbon-free. This study aims to evaluate the feasibility of ammonia-based power generation by conducting techno-economic and carbon footprint analyses of an integrated ammonia decomposition and phosphoric acid fuel cell system. Using a commercial process simulator, the power generation process is designed to reveal an energy efficiency of 46.7% and an upper limit for the ammonia price to compete with industrial electricity prices is identified as 421.3 $ tNH3–1 through economic analysis. Furthermore, the study establishes five different scenarios for ammonia import from the top ten exporting countries to the Republic of Korea (KOR), according to historical data, for optimization. Ammonia import is optimized in terms of exporting countries and quantities to satisfy the ammonia price while minimizing overall emissions using the Monte Carlo method for ammonia production costs and carbon dioxide emissions in each nation. The results show that carbon intensity falls within the range of 0.707–0.736 kgCO2-eq kWh−1, which exceeds the 20-year average value of carbon intensity in KOR if carbon-based ammonia is solely imported. However, the system can be competitive in terms of both economic and environmental aspects if the carbon–neutral ammonia ratio is over 78% (more than Scenario 4). In conclusion, this study statistically investigates the optimization results focusing on major ammonia export countries, identifies the trend of carbon intensity in the scenarios, and provides guidelines for reducing overall carbon intensity by considering the production, transportation, and utilization of ammonia. Ammonia is emerging as a promising energy source to achieve carbon neutrality due to its inherent carbon-free nature. A recent study, led by Professor Hankwon Lim in the School of Energy and Chemical Engineering and the Graduate School of Carbon Neutrality at UNIST, has evaluated the feasibility of ammonia-based power generation through techno-economic and carbon footprint analyses. The research focuses on an integrated system combining ammonia decomposition and phosphoric acid fuel cells. The study, conducted using a commercial process simulator, unveils significant findings regarding the efficiency and economic viability of utilizing ammonia in power generation systems. Results indicate an impressive energy efficiency rate of 46.7% within the designed power generation process. Figure 1. (a) Cost breakdown of the levelized cost of electricity (LCOE) in the case of industrial electricity prices (20-year average of 0.075 $ kWh−1), (b) the change in ammonia import prices, electricity prices, and calculated LCOE in the ammonia-based power generation using phosphoric acid fuel system, and (c) difference between industrial electricity price and calculated LCOE in the system with longer plant operating period and scaled-up capacity. Through comprehensive economic analysis, the research team identified an upper limit for ammonia pricing at 421.3 $ tNH3–1 that allows competitive pricing against industrial electricity rates—a crucial factor in determining market competitiveness. To further optimize ammonia imports into the Republic of Korea (KOR), five distinct scenarios were established based on historical data from the top ten exporting countries. Using the Monte Carlo method for ammonia production costs and carbon dioxide emissions in each nation, researchers optimized import quantities while minimizing overall emissions. The results demonstrate that if solely reliant on carbon-based ammonia imports, carbon intensity ranges between 0.707–0.736 kgCO2-eq kWh−1—exceeding KOR's average value over a 20-year period. However, achieving a ratio of over 78% of carbon-neutral ammonia (Scenario 4) can make both environmental and economic aspects more favorable. Figure 2. Optimization results for importing ammonia from the top ten exporting countries (Scenario 3); The circle size represents the amount of imported ammonia and the color represents the ratio of carbon-based to carbon–neutral ammonia (gray indicates carbon-based ammonia and blue indicates carbon–neutral ammonia). (For interpretation of the references to color in this figure legend, the reader is referred to the web version of this article.) According to the research team, their findings provide valuable insights into optimizing ammonia exports and reducing carbon intensity. By adopting a holistic approach that encompasses all stages of the supply chain, significant progress can be made towards sustainable energy solutions. "Our study sheds light on the immense potential of ammonia as an energy source," said Professor Lim. "We have analyzed costs and greenhouse gas emissions while considering different commercialized methods of producing ammonia. Although renewable energy sources were not part of this particular study, our findings offer crucial insights into enhancing ammonia exports and promoting sustainability." Figure 3. Optimization results for the ammonia-based power generation system using a phosphoric acid fuel cell in terms of carbon intensity considering production, transportation, and decomposition of ammonia for each scenario: (a) bar chart and 100 data points, (b) histogram and kernel density estimation distribution, and (c) percentage of emissions attributed to production, transportation, and power generation. The study findings have been published ahead of their official publication in the online version of Chem. Eng. J. on May 13, 2023. This work has been supported by the National Research Foundation of Korea (NRF), the Carbon Neutrality Demonstration and Research Center of UNIST, the Ministry of Trade, Industry and Energy and Korea (MOTIE), and Korea Evaluation Institute of Industrial Technology (KEIT). Their findings are expected to contribute to advancing the understanding and utilization of ammonia as a viable option for decentralized power generation systems. Journal Reference Dongjun Lim, Jong Ah Moon, Yeong Jin Koh, et al., "Expansion and optimization of ammonia import to the Republic of Korea for electricity generation," Chem. Eng. J., (2023).

UNIST today announced that it has entered a strategic partnership with the Abu Dhabi National Oil Company (ADNOC), the largest state-run oil company in the United Arab Emirates (UAE), to lead the global digital carbon-neutral market. This partnership aims to lead the development of a decarbonization optimization system for large-scale oil refining and petrochemical processes, leveraging the power of Artificial intelligence (AI). The signing of the Strategic Collaboration Agreement (SCA) between UNIST and ADNOC took place in the Abu Dhabi Energy Center in the UAE at 2 PM on May 10, 2023. The agreement was signed by UNIST President Yong Hoon Lee, Chief Technology Officer Sophie Hildebrand at ADNOC, and President Omar AI Marzooqi at AIQ, ADNOC's AI joint venture. From left are AIQ CEO Omar Al Marzooqi, Executive Director Musabbeh Al Kaabi of Low Carbon Solutions & International Growth, CTO Sophie Hildebrand of ADNOC, Executive Director Abdulmunim Saif Al Kindy of ADNOC's Upstream Directorate, UNIST President Yong Hoon Lee, and Director Hankwon Lim of UNIST Carbon Neutrality Demonstration and Research Center. The joint efforts of UNIST and ADNOC will launch two digital carbon-neutral leading projects in the second half of this year. These projects are focused on developing AI technology for the optimization of continuous multi-step processes of liquid chemicals in oil and petrochemical plants, as well as environmental monitoring systems that utilize AI and satellite images. Additionally, a digital carbon-neutral joint research center will also be established as early as this year. When the joint research center is launched, they plan to push for the following three tasks: "Development of optimized refining processes using AI," "Decarbonization and sustainable refining processes," and "Building of an eco-friendly hydrogen industry model." Under this partnership, the two organizations have agreed to cooperate closely with central and local governments, research institutes, and private companies in both South Korea and the UAE. Additionally, they will actively cooperate in establishing a "digital carbon neutral strategic partnership" at the national level, with the participation of others. This partnership will enable both organizations to leverage their respective strengths and expertise to lead the global digital carbon-neutral market. UNIST and ADNOC are committed to achieving sustainable development and mitigating the impact of climate change, and this agreement is a significant step towards that goal. To achieve these goals, both parties have agreed that a delegation from ADNOC Group will visit UNIST and Ulsan City in the second half of this year to discuss specific measures for cooperation. The three parties seek to discuss the possibility of hosting a joint event on the topic of 'Global Digital Carbon Neutral' at the 28th Conference of the Parties on Climate Change (COP 28), which will take place in Dubai at the end of November. They will also work to expand their cooperation at the government level, including cooperation with the Ministry of Science and ICT (MSIT). Attendees at the ceremony are posing for a group photo. The ceremony has been also attended by Executive Director Abdulmunim Saif Al Kindy of ADNOC's Upstream Directorate and Executive Director Musabbeh Al Kaabi of Low Carbon Solutions & International Growth. Earlier in March, UNIST officials along with Mayor Doo-gyum Kim of Ulsan Metropolitan City, and other delegations visited the UAE to discuss ways to establish strategic cooperation with ADNOC for digital carbon neutrality. As a result of these discussions, the two entities have agreed to launch leading projects, establish a joint research center, and co-host COP-28. "Through this agreement, UNIST has secured its position as a leading organization in the global digital carbon neutrality field," stated UNIST President Lee, expressing his satisfaction with the agreement. "We aim to expand strategic cooperation between Korea and the UAE with ADNOC's return visit in the second half of this year, serving as a catalyst." UNIST has been at the forefront of research in the digital carbon-neutral field, collaborating with the Graduate School of Artificial Intelligence, which was established in 2020. In 2022, UNIST opened the Graduate School of Carbon Neutrality to further its research efforts in this field and promote global cooperation. ADNOC Group, which signed a strategic collaboration agreement with UNIST, is led by Dr. Sultan Ahmed Al Jaber, the Minister of Industry and Advanced Technology, who also chairs COP-28. ADNOC has allocated $15 billion (approximately 20 trillion won) towards its low-carbon growth budget and has established the "low-carbon international growth sector" to address climate change.

Launched in 2022 within the UNIST Engineering Research Institute, the UNIST Carbon Neutrality Demonstration and Research Center has been promoting the scale-up demonstration based on low-carbon source technology, encompassing the entire cycle of carbon neutrality demonstration. The center aims to provide the best corporate-friendly business solution not only in the traditional industries, but in the environmentally friendly industries, or the so-called green industries for the future. It also intends to serve as a platform that connects industry, academia, public research organization, and government to drive collaborative innovation. Accordingly, the UNIST Carbon Neutral Demonstration Research Center has recently embarked on a new partnership with Carbon Value Co., Ltd. to pursue collaboration on fundamental, academic research related to carbon capture, as well as the demonstration of key carbon neutrality technologies. From left are Director Hankwon Lim of UNIST Carbon and Neutrality Demonstration and Research Center and President Deoksoo Ko of Carbon Value Co., Ltd. A ceremony to mark the signing of a Memorandum of Understanding (MoU) between the two organizations also took place at UNIST on March 28, 2023. The ceremony has been attended by Dean Sung Youb Kim of UNIST Engineering Research Institute, Director Hankwon Lim of UNIST Carbon Neutrality Demonstration and Research Center, Professor Yongwon Seo (Head of Graduate School of Carbon Neutrality), Professor Youngkook Kwon (School of Energy and Chemical Engineering, UNIST), President Deoksoo Ko of Carbon Value Co., Ltd., and other key representatives from both organizations. During the ceremony, Director Lim shared the overview, present condition, and future prospects for the UNIST Carbon Neutrality Demonstration and Research Center, the Graduate School of Carbon Neutrality, and the Carbon Neutral Institute. President Ko of Carbon Value Co., Ltd. also shared vision and goals for the future of Carbon Value Co., Ltd., and thus discussed his plans for joint research projects with UNIST. A signboard-hanging ceremony was also held to mark the official opening of the UNIST Carbon Neutrality Demonstration and Research Center. From left are President Deoksoo Ko of Carbon Value Co., Ltd. and Director Hankwon Lim at UNIST. The two organizations have agreed to cooperate in securing source technologies, including the rotating packed beds (RPBs) for CO2 capture and the process design and flow analysis related to H2 stripping technologies, specializing in CO2 capture and e-Fuel production. They have also decided to cooperate with each other in conducting commercial-level technology development, and actively consult with each other on business development, as well as the implementation plans for related technologies.

The UNIST Carbon Neutrality Demonstration and Research Center within the Engineering Research Institute at UNIST has embarked on a new partnership with Hanwha Corporation to pursue collaboration on carbon neutrality by promoting the use of low carbon materials in public sector. A ceremony to mark the signing of a Memorandum of Understanding (MoU) between the two organizations also took place at UNIST on March 21, 2023. Through the promotion of scale-up demonstration based on low-carbon source technology, encompassing the entire cycle of carbon neutrality demonstration, the center aims to provide the best corporate-friendly business solution not only in the traditional industries, but in the environmentally friendly industries, or the so-called green industries for the future. It also intends to serve as a platform that connects industry, academia, public research organization, and government to drive collaborative innovation. A group photo taken at the signing ceremony of MOU between the UNIST Carbon Neutrality Demonstration and Research Center Signs Cooperation MoU with Hanwha Corp. l Image Credit: Administration Office of Graduate School of Carbon Neutrality The ceremony has been attended by Dean Sung Youb Kim of UNIST Engineering Research Institute, Director Hankwon Lim of UNIST Carbon Neutrality Demonstration and Research Center, Professor Yongwon Seo (Head of Graduate School of Carbon Neutrality), Professor Youngkook Kwon (School of Energy and Chemical Engineering, UNIST), Business Development Manager ByeongNam Cho of Hanwha Corp., and other key representatives from both organizations. During the ceremony, Director Lim shared the overview, present condition, and future prospects for the UNIST Carbon Neutrality Demonstration and Research Center, the Graduate School of Carbon Neutrality, and the Carbon Neutral Institute. Business Development Manager ByeongNam Cho of Hanwha Corp. also shared vision and goals for the future of Hanwha Corp., and thus discussed their plans for joint research projects with UNIST.

Abstract Excessive fossil–fuel consumption to meet increased energy demand is considered as the main reason of the climatic change. To prevent this devastating change, hydrogen has gained much attention as an intermediate to replace fossil–fuel–based energy systems by sustainable green energy system. Since most of the H2 is produced through natural gas process, a trade–off in terms of huge amounts of CO2 emissions should be concerned. Accordingly, integration of the H2 production and carbon capture facility actively, called blue H2, emerges as a workable alternative. In addition, with the rise in CO2 demand, the liquefaction of captured CO2 has become an attractive strategy in terms of long–term storage and transportation. Therefore, a comprehensive study is performed to assess the feasibility of an integrated system based on carbon capture using monoethanol amine and four CO2 liquefaction systems such as Linde-Hampson, dual pressure Linde-Hampson, vapor compression refrigerant, and absorption refrigerant systems (later will use as case 1 to 4, respectively). Based on energy and exergy evaluations, case 4 reflects the higher efficiencies with specific energy consumption of 0.188el and 0.733th GJ ton CO2-1 and exergy efficiency of 85.55 %. In addition, techno-economic analysis calculates unit LCO2 production of each case; 22.19, 21.35, 21.00, and 24.60 $ ton-1 for cases 1, 2, 3, and 4, respectively. The quantified climate change impacts were estimated by life-cycle assessment; 0.629, 0.620, 0.608. and 0.674 kg CO2-eq kg LCO2-1 for cases 1, 2, 3, and 4, respectively. Furthermore, analytic hierarchy process is performed to provide comprehensive guidelines of liquefied CO2 production under technical, economic, and environmental aspects. A research team, led by Professor Hankwon Lim (Graduate School of Carbon Neutrality) in the School of Energy and Chemical Engineering at UNIST carried out a comprehensive assessment in terms of 4E (Energy, Exergy, Economic, and Environmental)'s analysis of CO2 liquefaction in conjunction with the production of blue hydrogen. According to the research team, the current study provides the insights of carbon capture and liquefaction (CCL) from flue gas. They further noted that this is the very first study which discusses the technical, thermodynamic, economic, and environmental aspects of CCL process. In addition, analytic hierarchy process (AHP) was also performed to provide comprehensive guidelines of liquefied CO2 production under technical, economic, and environmental aspects. A thorough analysis has been conducted in this study from various perspectives, which in turn help assist the overall benchmark of an eco-friendly process that is energy efficient economical, and environmentally benign. The process analysis section is divided into four subsections, namely 4E (Energy, Exergy, Economic, Environmental), as well as Analytic hierarchy process (AHP) analysis. Figure 1. Schematic image, describing the process analysis to achieve pure and liquefied CO2. Hydrogen (H2) has attracted considerable attention as an energy carrier for future energy goals to replace fossil–fuel based energy system. The major source of H2 is reforming of natural gas, which results in huge amounts of CO2 emissions. However, the integration of the H2 production together with the carbon capture facility has been designated as emerging approach as a workable alternative. Consequently, the utilization of captured CO2 has been suggested as viable solution for mitigating the climate change. Therefore, storage and transportation of captured CO2 is one of the most crucial factors to be considered for sustainable solutions. In this regard, technical, economic, and environmental assessments were made for an integrated carbon capture and liquefaction process to provide the basic insights. As a result, energy and exergy analysis of proposed processes demonstrate that the case 4 reflects minimum specific energy consumption (0.188el and 0.733th GJ/ton) with exergy efficiency of 85.55 %. Moreover, unit LCO2 production was calculated as 22.19, 21.35, 21.00, and 24.60 $ ton-1 for cases 1, 2, 3, and 4, respectively, in a result of economic evaluation. The climate change impacts were quantified as 0.629, 0.620, 0.608. and 0.674 kg CO2-eq kg LCO2-1 for cases 1, 2, 3, and 4, respectively. Therefore, it can be concluded that case 3 can become a satisfactory alternative for CO2 liquefaction in terms of technical, economic, and environmental perspectives at once. The findings of this research have been published in the online version of Applied Energy on February 15, 2023. This study has been supported by the Carbon Neutrality Demonstration and Research Center of UNIST. Journal Reference Changgwon Choe, Junaid Haider, Hankwon Lim, "Carbon capture and liquefaction from methane steam reforming unit: 4E’s analysis (Energy, Exergy, Economic, and Environmental)," Applied Energy, (2023).

Abstract As deviations in H2 production capacity by countries become a considerable barrier to the realization of the global H2 economy, international trade between countries with abundant resources and those with limited resources is required. In line with this trend, numerous supply chains between several countries have been planned, and associated studies have been conducted. However, the study which treats international overseas H2 trade chains considering numerous major importing and exporting countries has rarely been conducted before. In this study, a comprehensive optimization for the overseas H2 supply chain considering the three major importing countries including Korea, Japan, and Germany was conducted with mixed-integer linear programming considering both economic and environmental aspects simultaneously. Through the optimization study, the most feasible H2 supply chains for each importing country could be verified according to years and case scenarios. Blue H2 from Qatar turns out to be the most feasible supply chain for Japan in 2030, while green H2 from South Africa is the most feasible one for other importing countries. In 2040, green H2 from South Africa and Australia becomes the best one for Asian importers, and Australia finally dominates all the supplies after 2050. In the case of Germany, green H2 from Spain is considered the best after 2040. Depending on the scenario, the difference in the selected countries and supply amounts is not significant, though the costs are varied. Ammonia turns out to be the most feasible carrier for H2, and the total cost including the carbon tax ranges from 2.15 to 3.43 $ kgH2–1, which is a range from the current green H2 to the blue H2 price. Hydrogen (H2) has been regarded as a promising alternative energy carrier to replace fossil fuels. It is also important as a future clean energy source to achieve carbon neutrality since it does not emit carbon dioxide (CO2). However, the cost of storing and transporting H2 have been the major challenge for the realization of H2 economy. A research team, led by Professor Hankwon Lim from the Graduate School of Carbon Neutrality at UNIST has presented optimal supply chains considering economic and environmental aspects to materialize international trade of decarbonized H2. In this study, a comprehensive optimization for the overseas H2 supply chain considering the three major importing countries including Korea (KOR), Japan (JPN), and Germany (DEU) was conducted with mixed-integer linear programming considering both economic and environmental aspects simultaneously. Through this optimization study, the research team verified the most feasible H2 supply chain for each importing country according to years and case scenarios. Figure 1. Overall schematic diagram of this study. According to the research team, the optimization proceeded, respectively, for 3 case scenarios (base, conservative, and optimistic) and 3 years (2030, 2040, and 2050) by considering the demands of 3 major importers (KOR, JPN, DEU), capacities and resource prices of 16 exporters (AUS, BRA, CHL, and so on), amount of comparison of supplied H2, and H2 carriers (LH2, toluene/MCH (TOL/MCH), and NH3). Their findings showed that in 2030, blue H2 from QAT is the most feasible supplier for JPN, while green H2 from ZAF is the most feasible supplier for KOR and DEU. In 2040, green H2 from AUS also becomes one of the feasible suppliers for KOR and JPN together with ZAF and finally dominates the supplies after 2050, while green H2 from ESP is considered to be the most feasible one for DEU after 2040. Figure 2. Sankey diagrams of the most optimal chains for the base case scenario, considering both economic and environmental aspects. In the case of exporters, blue H2 is indicated in blue, while green H2 is indicated in green. In the case of importers, KOR, JPN, and DEU are indicated in red, orange, and turquoise, respectively. "Although the difference between scenarios is not significant, the overall costs are different," noted the research team. "One difference is that green H2 from AUS is selected as a more feasible supplier for KOR rather than ZAF in 2040 with the optimistic case scenario." The study also found that ammonia (NH3) turns out to be the most feasible carrier for H2 and the total cost including the carbon tax has a range from 2.15 to 3.43 $ kgH2–1 which is between the current green H2 and blue H2 price ranges. The study also found that ammonia turns out to be the most feasible carrier for H2. According to the results of the economic and environmental assessments conducted, the price of hydrogen supply, including carbon taxes generated by greenhouse gas emissions, ranged from 2.15 to $3.43 per kilogram. Based on the results, countries that are scheduled to introduce hydrogen (Korea, Japan, and Germany) have derived scenarios for optimizing the hydrogen supply chain that are needed in the future. This study has been supported by the Hydrogen Energy Innovation Technology Development Program of the National Research Foundation of Korea (NRF), funded by the Ministry of Science and ICT (MSIT) and also supported by the Korea Institute of Energy Technology Evaluation and Planning (KETEP). Published in the January 2023 issue of ASC Sustainable Chemistry & Engineering, their findings have also been featured as a front cover. Journal Reference Ayeon Kim, Heehyang Kim, Dongjun Lim, et al., "Materializing International Trade of Decarbonized Hydrogen Through Optimization in Both Economic and Environmental Aspects," ACS Sustain. Chem. Eng., (2022).

Abstract In this study, we examine the effects of manager's perspectives on climate change on stock price crash risk. The analysis confirms that manager's climate change perspective is negatively associated with future stock price crash risk likelihood. Various channel tests show that investor attention and analyst coverage are potential channels through which a firm's climate change perspective improves financial stability and ultimately reduces crash risk. Our results are also robust to alternative climate change perspective measures. The issues associated with climate change and carbon neutrality pose significant challenges to the economic and financial systems. As climate change risks do not unidirectionally affect firms, it is important to understand how firms and managers perceive climate change effects, according to a recent study on the awareness of climate change and the influences of financial market conditions. A research team, led by Professor Chang-Keun Song in the Graduate School of Carbon Neutral has examined the effects of managerial perspectives on climate change on stock price crash risk. Their study shows that firm-level climate change perspective may have a positive effect on reducing a firm's crash risk likelihood. Figure 1. Change of crash risk measures with respect to climate change perspective level. In this study, the research team conducted various channel tests to understand the underlying mechanism between climate change perspective and crash risk. They construct firm-level time-varying climate change perspective measures using machine learning methods. Using climate change perspective calculated from earnings call transcripts, the research team suggested that a higher perspective of global climate change issues attracts the attention of external parties, such as investors and financial analysts, whose monitoring reduces a firm's negative information withholding behavior. "Our study provides strong evidence supporting signaling theory and offer practical contributions for a firm's sustainable development," noted the research team. Their findings have been published in the January 2023 issue of Finance Research Letters, a peer-reviewed academic journal covering research on all areas of finance. Journal Reference Hail Jung and Chang-Keun Song, "Managerial perspectives on climate change and stock price crash risk," Finance Res. Lett., (2023).