Global Decarbonization Research Articles

A process-oriented model to measure product carbon footprint: an exploratory study based on multiple cases

Climate change is global challenge and decarbonisation becomes top agenda for manufacturing firms. As it is generally recognized that only the measured get managed, an understanding and measuring of the Product Carbon Footprint (PCF) is now needed. International standards have provided the basic steps for carbon footprint measurement, yet, in practice, there is knowledge insufficiency and high cost. This paper aims to answer the research question: ‘How can companies conduct PCF measurement projects effectively?’. This research adopts the qualitative method with multiple case studies. Data is collected through interviews with operation managers and the sustainability specialists of nine manufacturing companies, with a focus on the motivation and details of activities relating to their PCF measurement projects. Through within-case and cross-case analysis, a process model is proposed alongside the identification of three types of PCF, trial-oriented, process-oriented, and market-oriented PCF. A series of tailored measurement process models are further developed according to the PCF scenarios. The holistic process model contributes to the understanding of a PCF measurement that is based on empirical evidence. Practically, the process model can serve as a ‘cookbook’ to implement PCF measurement projects.

Decarbonizing the Atmosphere Using Carbon Capture, Utilization, and Sequestration: Challenges, Opportunities, and Policy Implications in India

The IPCC’s (Intergovernmental Panel on Climate Change) special report highlights the urgent necessity of limiting global warming to 1.5 °C, prompting a vital exploration of decarbonization methods. Carbon capture and sequestration (CCS) play a pivotal role in reducing carbon dioxide emissions from industrial processes and power generation, helping to combat climate change and meet global decarbonization goals. This article focuses on the economic prospects and market potential of carbon capture technologies in India, specifically in utilizing captured CO2 in the power, petrochemicals, and fertilizer sectors. It also emphasizes decarbonization through carbon sequestration involving geological storage to extract carbon dioxide from the environment, ultimately reducing greenhouse gas emissions. This article stresses the need to develop new technologies for carbon capture, utilization, and sequestration to overcome technical and financial barriers. It highlights the importance of improving efficiency, reducing costs, and scaling up these technologies for widespread adoption. Additionally, this study delves into the essential policy and regulatory frameworks for CCUS implementation, emphasizing the need for standards and laws to ensure safety, environmental protection, and effective monitoring in the Indian context. The research findings and recommendations provide valuable insights for future CCUS implementation, advancing sustainable decarbonization efforts in India and globally.

Emission pathways and mitigation options for achieving consumption-based climate targets in Sweden

National emission reduction targets under the Paris Agreement have a territorial focus, incentivizing mitigation actions domestically. Here we examine the theoretical basis for adopting complementary consumption-based net-zero emission targets and assess the consequences of adopting such proposed targets for Sweden. We apply scenario analyses based on a prospective lifecycle assessment framework. The framework is a hybrid of bottom-up simulations for passenger travel, construction and housing, and food, and top-down analyses for remaining consumption. In this work, we show how consumption-based climate targets may accentuate the need for new demand-side climate policies that contribute to reducing emissions along supply chains of products and services. Our scenario analysis suggests that combining advanced mitigation technologies with behavioral changes could reduce emissions from 9.8 tons of carbon dioxide equivalents per capita in 2019 to between 2.7 and 4.8 tons by 2045 for Swedish residents, depending on global decarbonization pathways.

Scrap endowment and inequalities in global steel decarbonization

Scrap steel recycling, powered by emission-free electricity, can produce nearly zero-emission steel at a lower cost than alternative primary production. However, the feasibility of this production method depends on future scrap availability. This study highlights the unequal distribution of future scrap availability worldwide, with the Global North having abundant scrap, while the Global South faces impending scarcity unless scrap is imported. By 2050, the European Union, North America, and developed Asia and Oceania could hold stocks of end-of-life scrap that are equal to their entire steel demand, if they chose to do so. China could also have domestic end-of-life scrap equivalent to about half of its cumulative demand. Conversely, developing countries, such as India and states in Africa, are expected to have severely limited domestic end-of-life scrap, representing less than 5% of their cumulative demand without international trade. This disparity, referred to as “scrap endowment”, is a consequence of the Global North's historical carbon emissions. The scrap endowment enables the Global North to produce zero-emission steel at a relatively low cost, while the Global South grapples with limited, more costly options. These findings imply the need for equity-focused mechanisms to assist the Global South if both hemispheres are to achieve net-zero emissions by 2050, or soon thereafter.

Investigation of Cooling Techniques for Roof-Mounted Silicon Photovoltaic Panels in the Climate of the UAE: A Computational and Experimental Study

The increased adoption of photovoltaic (PV) systems for global decarbonisation necessitates addressing the gap in reduced panel efficiency due to overheating. This issue is especially prominent in countries with extremely hot and humid climates where PV utilisation is hindered by declining panel output. A systematic review of PV cooling techniques suggests passive systems are more economical, sustainable, and easier to implement than active systems, despite possessing a lower cooling potential. Air-based systems were deemed the most viable for the UAE’s climate, considering both performance and cost. Based on these findings, two individual improvements for air-based cooling systems were combined in an attempt to achieve greater cooling: a segmented multiangular aluminium fin heatsink developed from previous works. Various perforation patterns were simulated on the chosen heatsink using CFD software to determine the most optimal arrangement. The original and optimised models were both tested under real-life conditions in Dubai, United Arab Emirates, revealing similar cooling potential between the two. The results of this study indicate that the PV cell temperature can be decreased by up to 10 °C with the placement of an aluminium fin heatsink, which corresponds to an approximate efficiency increase of 5%.

Identifying generalizable equilibrium pricing strategies for charging service providers in coupled power and transportation networks

Transportation electrification, involving large-scale integration of electric vehicles (EV) and fast charging stations (FCS), plays a critical role for global energy transition and decarbonization. In this context, coordination of EV routing and charging activities through suitably designed price signals constitutes an imperative step in secure and economic operation of the coupled power-transportation networks (CPTN). This work examines the non-cooperative pricing competition between self-interested EV charging service providers (CSP), taken into account the complex interactions between CSPs' pricing strategies, EV users' decisions and the operation of CPTN. The modeling of CPTN environment captures the prominent type of uncertainties stemming from the gasoline vehicle and EV origin-destination travel demands and their cost elasticity, EV initial state-of-charge and renewable energy sources (RES). An enhanced multi-agent proximal policy optimization method is developed to solve the pricing game, which incorporates an attention mechanism to selectively incorporate agents' representative information to mitigate the environmental non-stationarity without raising dimensionality challenge, while safeguarding the commercial confidentiality of CSP agents. To foster more efficient learning coordination in the highly uncertain CPTN environment, a sequential update scheme is also developed to achieve monotonic policy improvement for CSP agents. Case studies on an illustrative and a large-scale test system reveal that the proposed method facilitates sufficient competition among CSP agents and corroborates the core benefits in terms of reduced charging costs for EV users, enhancement of RES absorption and cost efficiency of the power distribution network. Results also validate the excellent generalization capability of the proposed method in coping with CPTN uncertainties. Finally, the rationale of the proposed attention mechanism is validated and the superior computational performance is highlighted against the state-of-the-art methods.

Assessing the efforts of coal phaseout for carbon neutrality in China

As the world's largest producer and consumer of coal, coal phaseout is critical for China to achieve carbon neutrality and contribute to global decarbonization. Here, utilizing the Global Change Assessment Model, this paper simulates China's coal phaseout pathways at the sectoral level between 2015 and 2060, considering the deployment of carbon capture and storage (CCS). The results show that China's coal consumption peaks at 96.4 Exajoules (EJ) in approximately 2020 and needs to decrease to 10.9 EJ by 2060 to achieve carbon neutrality. Specifically, the power sector bears the most significant proportion of responsibility, as its coal consumption must fall to 1.4 EJ by 2060, which is approximately 97.2% lower than the peak in 2020. The industrial sector is next and needs to decrease consumption to 9.2 EJ of coal in 2060, which is a reduction of 32.3 EJ below the 2020 level. Electricity will replace coal as the dominant energy source in the industrial sector after 2040. However, a portion of feed coal will remain in the industry for a long time. Among the industrial subsectors, the steel sector needs to put significant pressure on efforts to phase out coal, followed by the cement and nitrogen fertilizer sectors. In 2060, these three sectors will consume 5.7 EJ of coal, accounting for 64.1% of the total coal consumption in the industrial sector. The deployment of coal-CCS is one of the alternatives to achieve carbon neutrality and ensure smooth coal phaseout. Under the carbon neutrality scenario, the annual deployment of coal-CCS needs to exceed 0.13 EJ from 2025 to 2045, with a peak at 3.3 EJ in 2045.

Overview of Ni-Based Catalysts for Hydrogen Production from Biogas Reforming

The environmental impact and the forecasted scarcity of fossil fuels have intensified research on renewable energy sources. Hydrogen is a versatile energy carrier that can be produced from renewable sources and plays a key role in achieving global decarbonization targets. Biogas, produced by anaerobic digestion of organic compounds, is rich in methane and carbon dioxide and can be used to produce renewable hydrogen by dry reforming. This review focuses on the recent advances in Ni-based catalysts for biogas reforming. The effect of supports and promoters on catalyst activity, stability, and resistance to carbon deposition will be systematically discussed. This review provides a better understanding of the influence of the synthesis method, metal-support interaction, acid/base sites, and oxygen mobility on catalytic activity. Special emphasis will be given to the development of core-shell structure catalysts and bimetallic catalysts of Ni with other transition metals and noble metals.

An overview on the technologies used to store hydrogen

Hydrogen energy has a significant potential in mitigating the intermittency of renewable energy generation, by converting the excess of renewable energy into hydrogen through many technologies. Also, hydrogen is expected to be used as an energy carrier that contribute to the global decarbonization in transportation, industrial, and building sectors. Many technologies have been developed to store hydrogen energy. Hydrogen can be stored to be used when needed and thus synchronize generation and consumption. The current paper presents a review on the different technologies used to store hydrogen. The storage capacity, advantages, drawbacks, and development stages of various hydrogen storage technologies were presented and compared.

Selection and Evaluation of Economic and Emission Reduction Benefit of a Mine Electrification System for Transportation in Deep Opencut Copper Mines

The Paris Agreement's global decarbonization drive has heightened the need for sustainable energy options, shifting focus away from fossil fuels. Copper, a crucial metal in this transition, will face increased demand, necessitating deeper opencut mines. However, this poses issues as traditional fuel-intensive trucks used for mine haulage result in substantial Scope 1 emissions and rising operational costs. This study addresses the urgency to explore alternative mine haulage systems that minimize fuel consumption and associated emissions while maintaining economic viability. It evaluates potential systems at "The Copper Pit," a Latin American copper mine, based on capital cost, operating cost, flexibility, safety, technological readiness, and emission abatement potential. Using the Analytical Hierarchy Method, weightage values for each criterion are calculated, resulting in a prioritized ranking table. Trolley Assist truck haulage emerges as the most promising alternative, showcasing impressive savings of up to 87% in fuel consumption and associated emissions, and an 80% reduction in running costs. Economic advantages are affected by diesel and power prices, with the carbon tax having the smallest impact. The study recommends a feasibility study for Trolley Assist implementation in the Copper Pit and a staged approach to minimize risks. Despite being less flexible and requiring upfront capital, Trolley Assist holds promise for deep copper mines, significantly reducing emissions and operating costs, ensuring sustainable and profitable mining operations.

Renewable energy integration in offshore oil and gas installations

As the oil and gas industry seeks to reduce its carbon footprint and align with global decarbonization goals, integrating renewable energy sources into offshore operations presents a promising pathway. This review examines the feasibility of incorporating renewable energy technologies such as offshore wind, solar, and marine energy into the power supply of oil and gas installations. Offshore wind energy, with its high potential and scalability, emerges as a viable option for powering rigs, as demonstrated by projects like Hywind Tampen in Norway, which uses floating wind turbines to supply energy to oil platforms. Solar energy, while more limited in offshore environments due to space and weather constraints, can be part of hybrid systems combining multiple renewable sources. Marine energy, including tidal and wave power, is still in its developmental stages but holds promise for future applications. The review explores hybrid energy systems that integrate renewable sources with conventional energy, such as gas turbines, to ensure continuous power supply. Microgrid technologies and energy storage solutions are also discussed as essential components for balancing renewable energy’s intermittency and optimizing power distribution. Key challenges, such as the harsh marine environment, high initial investment, and the need for new infrastructure, are analyzed alongside potential solutions like technological innovations in floating renewable systems and automated monitoring technologies. Economic feasibility is considered through a cost-benefit analysis, highlighting the potential long-term savings from reduced fuel use and the benefits of regulatory incentives for renewable energy integration. Ultimately, the integration of renewables not only supports decarbonization but also offers operational efficiency and cost reduction opportunities. This review concludes by examining future trends in renewable energy for offshore installations and the potential for fully electrified, sustainable oil and gas platforms.

(Invited) Electrochemical Engineering: From Membranes to MW Green Hydrogen Stacks

With the increasing availability and rapid price decrease of clean electrons, electrochemical engineering has become a frontier for fundamental research, innovation, entrepreneurship, and industrialization, making enormous contributions to the global decarbonization effort. In this presentation, I will share our journey and lessons from having a simple concept – hydroxide exchange membrane or HEMs – more than fifteen years ago to the founding of Versogen to the commercialization of the PiperION membranes to the development of a pure-water fed MW stack for green hydrogen production.

(Invited) Hydroxide Exchange Membrane Electrolyzers for Green Hydrogen: From Organic Chemistry to MW Stacks

With their increasing availability and rapid price decrease, clean electrons have been leading the way for our global decarbonization efforts. However clean electrons have limitations and cannot access certain sectors of our economy. Green hydrogen as a molecule has unique advantages over clean electrons in areas of chemical synthesis, heavy duty transportation, and long duration and cross sector energy storage. In this presentation I will share our past and latest work on hydroxide exchange membranes, electrocatalysis including electrochemical interface work, and the effort to develop a pure water-fed MW HEM electrolzyer stack.

A Mathematical Framework for Modeling Energy Dense Redox-Mediated Flow Batteries

Electrochemical processes can accelerate global decarbonization efforts by enabling the broad adoption of renewable electricity, facilitating the deployment of electric vehicles, and affording new opportunities in sustainable chemical manufacturing. However, this transition requires new electrochemical technologies with performance, cost, and scalability metrics that align with emerging demands. This need has inspired exploration into innovative systems that leverage unconventional materials and/or reactor designs. One such approach is the use of redox-mediated electrode reactions, which may expand the portfolio of feasible reactants, device configurations, and operating modes. In brief, a soluble and stable redox-couple (the mediator) is paired with an off-electrode material of interest (typically in the solid phase); this combination results in a two-step reaction system, where the mediator reacts on the electrode surface within an electrochemical cell before driving a separate redox reaction with the spatially removed material.1-2 Prior literature has shown how this approach can enhance the charge-storage capacity of redox flow batteries, facilitate difficult-to-perform electrochemical transformations, and unlock spatial and temporal flexibility in electrochemical processes.3-6 While promising, the performance of these systems is governed by coupled reactive-transport processes which present complex (and transient) interdependencies that frustrate navigation through the multi-dimensional design space. As such, technology development is slowed by the material- and time-intensive nature of experimental campaigns. To this end, modeling and simulation can offer an inexpensive and accelerated path to disaggregate interrelated physical processes, to quantify performance descriptors, and to inform experimental studies.7-8 In this presentation, we will describe a mathematical modeling framework that uses traditional chemical engineering principles to represent a redox-mediated electrochemical system consisting of a flow cell, a tank containing solid reactants, and a recirculating stream containing a soluble mediator. This domain aligns with common redox-mediated flow battery configurations, which enables both validation of the simulated electrochemical and fluid dynamic performance as well as insight into experimental observations reported in the literature. We will highlight the utility of low-dimensional models derived from this framework to provide deeper quantitative understanding into these phenomena. Through dimensional analyses, relevant dimensionless groups can be established that allow for generalization of model findings (e.g., scaling relationships, property tradeoffs) and articulation of design criteria for conceptual systems relevant to electrochemical energy storage and conversion. Acknowledgements This work was funded by the Skoltech – MIT Next Generation Program. N.J.M and B.J.N gratefully acknowledge the NSF Graduate Research Fellowship Program under Grant Number 2141064. Any opinion, findings, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the NSF. CTM gratefully acknowledges support under and awarded by the Department of Defense, Office of Naval Research, through the National Defense Science and Engineering Graduate Fellowship.

Tradeoffs in life cycle water use and greenhouse gas emissions of hydrogen production pathways

Hydrogen has been promoted as a key component of global decarbonization efforts, with various past studies estimating carbon emissions for several production pathways, but little past work has considered its water resource needs. This life cycle analysis considers hydrogen production on a per-kilogram basis for 11 pathways, fossil and non-fossil. It also includes impacts of treating water to the required quality for hydrogen production. Greenhouse gas emissions results were in a range of −15 to +31 kg CO2e/kg H2 produced. Water consumption varied more widely, from about 7 to 55 kg water/kg H2 for fossil-based pathways and 530 to 3400 kg water/kg H2 for biomass-based pathways. Electrolysis with various renewable electricity scenarios were also modeled. Overall, there are challenging tradeoffs to be navigated to achieve a low carbon and water footprint in hydrogen economy.

Greenly growing carbon nanotubes on graphene for high-performance lithium–sulfur batteries

The expanding energy storage market in response to global decarbonization goals generates countless waste, causing severe environmental issues. To address this dilemma, end-of-life batteries must be upcycled for a second life. Here we report an all-green strategy for growing carbon nanotubes (CNTs) on graphene. The graphene was upcycled from end-of-life lithium-ion batteries and the CNTs were then grown directly on the graphene by pyrolyzing biomass as the carbon source and yeast as the catalyst. When being used in a lithium–sulfur battery cathode, the graphene provided a highly conductive network while the CNTs enabled high sulfur loading and volume buffering, rendering the battery with high capacity, high stability, and long lifespan. The CNT/graphene constructed battery exhibited longevity of over 1500 cycles with a capacity fading rate of 0.042% per cycle and a steady Coulombic efficiency of over 97%. The all-green CNT/graphene hybrids present new pathways to upcycling batteries to second life.

Geothermal energy prospect for decarbonization, EWF nexus and energy poverty mitigation in East Africa; the role of hydrogen production

The affordability and availability of water and energy have a huge impact on food production. Research has shown that there exists a direct and indirect link between power production and clean water generation. Hence the inclusion/importance given to the energy-water-food (EWF) nexus in the United Nations' sustainable development goals. Acknowledging the importance of decarbonization to the global future, there exists a gap in literature on the development of models that can enhance the EWF nexus, reduce energy poverty, and achieve 100% renewable energy in the electricity sector. Therefore, the technical and economic prospect of geothermal energy for bridging the aforementioned gaps in existing works of literature is presented in this study. The energy poverty/wealthy status of a country has been confirmed to have a significant impact on economic development, as economic development is largely reflected in the food-water availability. Ditto, this study is focused on the interconnectivity of the EWF nexus while incorporating global decarbonization targets. Geothermal energy is of the utmost significance in East Africa due to its abundant potential and distinctive geological features. Located in the Great Rift Valley, the region has an abundance of geothermal reservoirs, making it an ideal location for geothermal power generation. This study is novel as a comprehensive assessment framework for energy poverty is developed and innovative models utilizing primarily the geothermal resource in the East African region to mitigate this problem are proposed and analyzed. The role of hydrogen generation from critical excess electricity production is also analyzed. The East Africa region is considered the case study for implementing the models developed. A central renewable energy grid is proposed/modelled to meet the energy demand for seven East African countries namely; Ethiopia, Tanzania, Uganda, Djibouti, Comoros, Eritrea, and Rwanda. This study considers 2030, 2040, and 2050 as the timestamp for the implementation of the proposed models. The hybrid mix of the biomass power plant, solar photovoltaic (PV), pumped hydro storage system and onshore wind power is considered to furthermore show the potency of renewable energy resources in this region. Results showed that the use of geothermal energy to meet energy demands in the case study will mitigate energy poverty and enhance the region's EWF.

Decarbonization of Transport and Oral Health

The decarbonization of transport is a global initiative aimed at reducing greenhouse gas emissions and addressing the risks of global warming. This article explores the potential connections between the decarbonization of transport and oral health, highlighting the need for further research in this area. Emissions from vehicle exhausts, such as carbon dioxide, methane, and nitrous oxide, may have a modest impact on the risk of early childhood caries and other oral health diseases like periodontal diseases, oral cancer, and dental caries. Active transportation, which promotes regular exercise, has beneficial effects on overall health, including stimulating salivary protein production and reducing the risk of diabetes and cardiovascular diseases, both of which are linked to poor oral health. Transitioning to electric vehicles can also reduce noise pollution, positively impacting mental well-being, which is associated with improved oral hygiene practices. Furthermore, the development of sustainable infrastructure, including efficient public transportation systems, can enhance access to dental services. Further research is needed to establish stronger evidence for these connections and to explore how the global decarbonization of transport agenda can incorporate oral health considerations.

Leveraging opportunity of low carbon transition by super-emitter cities in China

Chinese cities are core in the national carbon mitigation and largely affect global decarbonisation initiatives, yet disparities between cities challenge country-wide progress. Low-carbon transition should preferably lead to a convergence of both equity and mitigation targets among cities. Inter-city supply chains that link the production and consumption of cities are a factor in shaping inequality and mitigation but less considered aggregately. Here, we modelled supply chains of 309 Chinese cities for 2012 to quantify carbon footprint inequality, as well as explored a leverage opportunity to achieve an inclusive low-carbon transition. We revealed significant carbon inequalities: the 10 richest cities in China have per capita carbon footprints comparable to the US level, while half of the Chinese cities sit below the global average. Inter-city supply chains in China, which are associated with 80% of carbon emissions, imply substantial carbon leakage risks and also contribute to socioeconomic disparities. However, the significant carbon inequality implies a leveraging opportunity that substantial mitigation can be achieved by 32 super-emitting cities. If the super-emitting cities adopt their differentiated mitigation pathway based on affluence, industrial structure, and role of supply chains, up to 1.4 Gt carbon quota can be created, raising 30% of the projected carbon quota to carbon peak. The additional carbon quota allows the average living standard of the other 60% of Chinese people to reach an upper-middle-income level, highlighting collaborative mechanism at the city level has a great potential to lead to a convergence of both equity and mitigation targets.

Scalable Biomass-Derived Hydrogels for Sustainable Carbon Dioxide Capture.

Carbon capture and sequestration are promising emissions mitigation technologies to counteract ongoing climate change. The aqueous amine scrubbing process is industrially mature but suffers from low energy efficiency and inferior stability. Solid sorbent-based carbon capture systems present a potentially advantageous alternative. However, practical implementation remains challenging due to limited CO2 uptake at dilute concentrations and difficulty in regeneration. Here, we develop sustainable carbon-capture hydrogels (SCCH) with an excellent CO2 uptake of 3.6 mmol g-1 (400 ppm) at room temperature. The biomass gel network consists of konjac glucomannan and hydroxypropyl cellulose, facilitating hierarchically porous structures for active CO2 transport and capture. Precaptured moisture significantly enhances CO2 binding by forming water molecule-stabilized zwitterions to improve the amine utilization efficiency. The thermoresponsive SCCH exhibits a notable advantage of low regeneration temperature at 60 °C, enabling solar-powered regeneration and highlighting the potential for sustainable carbon capture to meet global decarbonization targets.