Search

The anticipated surge in hydrogen energy adoption underscores the pivotal role of social acceptance in determining the viability of hydrogen technologies (HTs). This review provides a comprehensive overview of acceptance research on HT, evaluating measurement tools and utilized models, identifying influencing factors, and analyzing academic discourse on HT diffusion. Drawing from 39 studies, it highlights key acceptance factors: trust, environmental attitudes, subjective knowledge, and perceived risks. Discourse analysis uncovers perceived barriers like trust deficits, infrastructural challenges, and financial constraints, while strategic considerations such as timing and transparency are identified as drivers. The findings emphasize an individual-centred perspective, heterogeneous operationalizations, and a lack of longitudinal studies. The authors propose increased downstream research, focusing on societal reactions to implemented technologies and considering both psychological and contextual factors. Adoption of multi-level and institutional perspectives is essential. • Environmental attitude is the most studied factor influencing H2 technology acceptance. • Education campaigns and support schemes are frequently cited to drive H2 adoption. • Focus on upstream research neglects acceptance dynamics. • 70% of studies reference established models; many detach theory from studied factors. • Adoption of multi-level perspectives and an increase in longitudinal studies needed. [ABSTRACT FROM AUTHOR]

The energy issue in both developed and developing countries remains vital. However, in developing countries, energy pressure is much greater. Despite this, few studies have examined credit, entrepreneurship, and energy transition in developing countries. We addressed this research gap by using the data collected from six regions in Burkina Faso. Employing the multivariate probit and the endogenous switching probit model, three scenarios are explored. We find that entrepreneurship promotes energy transition while access to credit is not useful to the energy transition. However, the joint effect of access to credit and entrepreneurship is 4 times higher for solar PV use and 3 times for biogas adoption. Access to credit promotes the energy transition when credit is devolved to the entrepreneur supporting the trinity rather than the trilemma. [ABSTRACT FROM AUTHOR]

• We examine the role of circular economy and inclusive green growth in promoting energy transition and carbon neutrality in Europe. • We used three-pronged empirical strategy framed in advanced dynamic econometrics. • The results reveal that lagged of CO 2 emissions is a positive predictor of CO 2 emissions. • We show that embracing circular economy and inclusive green growth will be highly beneficial towards the attainment of carbon neutrality. • We recommend policy measures that considers both current and past emissions to promote environmental quality. This paper examines the role of the circular economy and inclusive green growth in promoting energy transition and carbon neutrality for several European countries during 2009–2021, using an advanced econometric strategy. To achieve this objective, we employed a three-pronged empirical strategy. The first strategy involved standard panel specifications, such as pooled ordinary least squares, Fixed Effects, Roger panel regression, white panel regression, and Driscoll–Kraay standard errors. The second strategy explored the long- and short-term dynamics of the relationships using the dynamic specifications of the Generalised Method of Moments, comprising the augmented Arellano–Bond, Ahn–Schmidt, Arellano–Bond, and Arellano–Bover/Blundell–Bond estimators. It further controls for endoegeneity using the Two stages Lease Square (2SLS and Lewbel 2SLS). The third strategy employed the Machado and Silva quantiles via moments to re-evaluate the heterogeneity drivers of carbon neutrality. Furthermore, an alternative and complementary strategy based on the statistical procedures of Hausman–Taylor and Feasible Generalized Least Squares was employed to verify robustness. The findings suggest that prior carbon emissions positively predict future emissions. Also, our results reveal that the adoption of a circular economy, including green growth and renewable energy, can significantly contribute to reducing carbon emissions. In contrast, domestic economic drivers, and eco-innovation increase carbon emissions. We propose that policymakers mandate producers to oversee the entirety of their product life cycles as a means to mitigate carbon emissions. Furthermore, endorsing training programs and educational initiatives aimed at cultivating the requisite skills for the energy transition and the adoption of circular economy practices is imperative for ensuring the realization of a successful low-carbon economy. [ABSTRACT FROM AUTHOR]

The global climate issue is becoming increasingly serious, and studying the energy transition (ET) has proven to be an effective solution to this problem. The essence of climate mitigation is to address the issue of ensuring the public health (pH) of human beings. Still, the definitions of ET in existing literature are inconsistent, and Many researches overlook the definitions of ET in official documents and discuss the relationship between ET and pH. Therefore, this research utilizes panel data from 107 countries over the period 2000–2020 to construct an energy transition indicator based on the definition from the World Economic Forum (WEF). It also examines the link between ET and pH using a two-way fixed effects regression. In the current turbulent international environment, this paper also investigates this link in the context of composite risk control (CRC), financial risk control (FRC), economic risk control (ERC), and political risk control (PRC). The results show that ET can significantly improve pH, a conclusion that remains significant after being subjected to a range of robustness tests. The study exploring the mechanism impact on the relationship between ET and pH shows that CRC, FRC, ERC, and PRC all strengthen the effect of ET on pH, and the mechanism effect varies considerably between high-income and low- and middle-income countries (LMICs); ET is more significantly affected by the mechanism in LMICs than in high-income countries. Furthermore, this paper illustrates that ET does not differ by gender in improving pH among infants, while there are gender differences in adults by using the instrumental variable regression and GMM regression to mitigate the endogenous and heteroscedasticity issue for heterogeneity test. The study in this paper can not only inspire policy researchers on which aspects to promote ET, but also provide a direction for improving pH. [ABSTRACT FROM AUTHOR]

In this paper we study clean energy transition in a modified version of the Ramsey growth model by including nonrenewable and renewable resources as well as pollution externalities. The main difference from previous works is that we consider imperfect substitution between nonrenewable and renewable resources. We characterize the social optimum and show that the economy converges to a clean state in the long run. We then study the decentralized equilibrium and show that the economy converges to the same state even without regulation, but with higher environmental damage. Further, we investigate the properties of the taxation trajectory that drives the laissez-faire economy to follow the optimal path and show that it can be either increasing or decreasing over time. We identify different channels that influence the path of optimal taxation and show that it depends, among other things, on the level of capital, the cost of renewable energy and the degree of substitution between renewable and nonrenewable resources. • A growth model with nonrenewable and renewable resources and pollution externalities. • Nonrenewable and renewable resources are considered as imperfect substitutes. • Social optimum and decentralized equilibrium characterized. • Decentralized economy converges to the clean state even without regulation. • Optimal taxation trajectory can be increasing or decreasing over time. [ABSTRACT FROM AUTHOR]

Transitioning to a sustainable energy future necessitates innovative storage solutions for renewable energies, where hydrogen (H₂) emerges as a pivotal energy carrier for its low emission potential. This paper explores unlined rock caverns (URCs) as a promising alternative for underground hydrogen storage (UHS), overcoming the geographical and technical limitations of UHS methods like salt rock caverns and porous media. Drawing from the experiences of natural gas (NG) and compressed air energy storage (CAES) in URCs, we explore the viability of URCs for storing hydrogen at gigawatt-hour scales (>100 GWh). Despite challenges such as potential uplift failures (at a depth of approximately less than 1000 m) and hydrogen reactivity with storage materials at typical conditions (below temperatures of 100°C and pressures of 15 MPa), URCs present a flexible, scalable option closely allied with green hydrogen production from renewable sources. Our comprehensive review identifies critical design considerations, including hydraulic containment and the integrity of fracture sealing materials under UHS conditions. Addressing identified knowledge gaps, particularly around the design of hydraulic containment systems and the interaction of hydrogen with cavern materials, will be crucial for advancing URC technology. The paper underscores the need for further experimental and numerical studies to refine URC suitability for hydrogen storage, highlighting the role of URCs in enhancing the compatibility of renewable energy sources with the grid. • Detailed exploration of unlined rock cavern (URC) technology. • Analysis of URCs' potential for large-scale hydrogen storage. • Insights from historical use of URCs in compressed gas storage. • Examination of the opportunities and challenges in using URCs for hydrogen storage. [ABSTRACT FROM AUTHOR]

The main performance indicators of hydrogen energy production should be improved. However, improving these factors also increase the operational costs of the companies. Because of this issue, there is a need for a priority analysis so that it can be possible to focus on more important factors. Accordingly, the purpose of this study is to evaluate hydrogen production methods for global energy transition. In this process, a four-stage model has been proposed by getting evaluations from three different experts. Firstly, artificial intelligence-based decision-making can be implemented for expert prioritization. In the second stage, recommender system is conducted with collaborative filtering to complete the missing evaluations. Thirdly, selected criteria are weighted by using M-SWARA with QPFRS. Finally, method alternatives for hydrogen production are ranked via quantum picture fuzzy rough sets adopted VIKOR. The biggest contribution for doing this study is that artificial intelligence technique is integrated into the model and experts' importance coefficients are can be computed. Additionally, by using the collaborative filtering technique, empty evaluations can be filled scientifically. This contributes to the quality of the analysis process in many ways. Thanks to this technique, experts are given the opportunity not to answer questions they are not very sure about. The findings indicate that renewable energy expansion, energy efficiency and sustainable development are the most important criteria for global energy transition in hydrogen production. On the other side, the ranking results give information that thermal processes including steam methane reforming and biomass gasification is the most appropriate method alternatives for hydrogen production. Based on these analysis results, it is strongly recommended that research and development activities should be improved to increase the efficiency and effectiveness of the renewable energy projects. With the help of this issue, it can be much easier to increase the performance of hydrogen production process. • Hydrogen production methods are evaluated for global energy transition. • A four-stage model has been proposed. • Selected criteria are weighted by using M-SWARA. • Method alternatives for hydrogen production are ranked via VIKOR. • Renewable energy expansion is the most important criteria. [ABSTRACT FROM AUTHOR]

The catastrophic effects of climate change can be mitigated by transitioning to renewable energy sources such as wind, solar, and hydropower while utilizing hydrogen (H 2) as an energy carrier. As renewable fuel sources are intermittent and location-specific, large-scale, long-term storage options for H 2 must be explored with high necessity. Subsurface hydrogen storage in saline aquifers provides a vital scope to store H 2 gas in available pore voids with minimal environmental risk. In this work, a highly heterogeneous porous micromodel was used to study the immiscible two-phase dynamics at high-temperature, high-pressure saline aquifer conditions using computational fluid dynamics (CFD) simulation based on volume of fluid (VOF) method. A set of microfluidic experiments were carried out under atmospheric conditions to validate the numerical model. The VOF model was observed to show good agreement with microfluidic experiments. An unstable displacement pattern with viscous fingering was observed during various flow conditions that captured high pressure (15 and 25 MPa) and temperature conditions (323 and 343 K). It was observed that fingering displacement of brine limits the storage spaces for hydrogen, which consequently follows the high permeable path. As a result, only 0.272 fraction of brine was invaded by the H 2 at a temperature of 323 K and pressure of 15 MPa. A comparison between H 2 -brine and nitrogen (N 2)-brine flow dynamics revealed a 46% less storage capacity of porous media for H 2. Formations bearing high temperature (343 K) showed an 11.27% increase in H 2 storage capacity, while pressure increase had negligible effect. At low capillary number (Ca), more snap-off effects resulted in higher trapping of H 2 gas. This study aims to provide meaningful insights into the complexities of flow dynamics and displacement patterns that are crucial for optimizing hydrogen storage efficiency in saline aquifers and for potential 'white' hydrogen production. [Display omitted] • Hydrogen-brine two-phase flow was simulated in a heterogeneous porous media. • Simulation captures pressure and temperature conditions of geological aquifers. • Microfluidic experiments were carried out to validate the numerical model. • Viscous fingering under high-pressure and temperature limits hydrogen storage. • More snap-off effects lead to increased hydrogen trapping in porous media. [ABSTRACT FROM AUTHOR]

[Display omitted] • Exploring causes driving interest in SDGs 7 & 13 in the US. • Links among energy transition, fossil fuels, green innovation, economic complexity. • Using dynamic ARDL and FDC for long-medium and short-run causality. • Results revealed energy transition, fossil fuels, economic complexity boost CO 2 emissions. • Green innovation cuts CO 2 emissions, ecological impact in the long term. The United States, as the world's second-largest polluter, emitted a staggering 4.7 billion metric tonnes of carbon dioxide in 2020. During the Leaders' Climate Summit, the US president articulated precise targets for combating climate change, notably a 50 to 52 percent reduction in net CO 2 emissions from 2005 levels by 2030. Consequently, it becomes imperative to identify the pivotal factors that are driving this intensified dedication to achieving the Sustainable Development Goals (SDGs). Hence, it is vibrant to determine the basic causes propelling the intensified interest in meeting SDGs 7 and 13. From this perspective, this study explores the dynamic link between energy transition, fossil fuel energy, green innovation, and economic complexity index on CO 2 emissions and ecological footprint in the United States from 1980 to 2020. The dynamic Autoregressive-Distributed Lag (ARDL) simulations and Frequency Domain Causality (FDC) techniques are applied for long-medium and short-run causal association among the variables. Our empirical evidence shows that energy transition, fossil fuel energy, and economic complexity increase CO 2 emissions and ecological footprint. On the other hand, green innovation reduces CO 2 emissions and ecological impact only in the long term. The pragmatic outcomes suggest that authorities should inhibit Fossil Fuel Energy, concentrate on energy transitions, and include more renewable sources in the US energy mix. The findings would assist the United States in meeting SDGs 7 and 13. [ABSTRACT FROM AUTHOR]

Although firms' expectations on future price dynamics are key for monetary policy, we still lack information on the expected effect of the transition to a net-zero economy on future prices. This paper fills this gap in the literature using survey data collected in the first quarter of 2022 on Italian firms' expectations of the impact of the Fit-for-55 - the package established by the EU to achieve its climate targets - on the prices of the goods and services they purchase. First, it documents that almost half of the sample expects that the Fit-for-55 plan will increase their input costs over the short and medium term, while the rest foresee no effect on prices. Then, it shows that firms extrapolate their private experience of high energy prices and shortages in raw materials when forming their expectations. These are salient events that are likely to be recalled relative to the others stored in memory when forming expectatons. In contrast, aggregate information such as energy, oil, and gas prices do not enter the expectations formation process. Finally, a propensity score analysis shows that the expected price impact of the green transition shapes firms' pricing and investment choices such that firms expecting the transition to raise the prices of the inputs they will purchase in the medium term increase (or intend to increase) their selling prices more than the others and are more likely to invest in improving their energy efficiency. [ABSTRACT FROM AUTHOR]

We establish a bus market evolution model to explore the implications of subsidy policies in Hong Kong (HK) for the transition to a zero-emission bus (ZEB) fleet using an unsubsidized case as the benchmark scenario. Using the system dynamics (SD) approach, we capture the intricate feedback mechanisms among market share dynamics, cost considerations, consumer preferences, and competitive interactions within the bus market. These interactions are encapsulated within three pivotal feedback loops: scale economy, public acceptance, and bus market competition. We systematically integrate the HK-specific features of hydrogen buses (H-buses), battery electric buses (E-buses), and diesel buses (D-buses) from technical and economic perspectives and compare them to the benchmark scenario. The results show that only 66% of the bus fleet would be ZEBs by 2050, and this underscores the necessity for governmental financial incentives to expedite the transition to a fully zero-emission fleet. Furthermore, we evaluate various ZEB subsidy policy alternatives in terms of timing, intensity, and recipients. The analysis suggests that policies offering long-term and low-intensity subsidies are most beneficial, taking into account the cumulative effects and inherent delays associated with policy implementation. Importantly, the study highlights the critical balance that policymakers must achieve between short- and long-term objectives, especially given the counter-intuitive outcomes observed in the early stages of policies favoring H-buses exclusively. This study provides valuable policy insights for policymakers and upstream energy companies in HK, with potential applicability in wider real-world contexts. • Zero-emission bus alternatives are analyzed from technical and economic aspects. • Various feedback loops are considered for dynamic market analysis. • A counter-intuitive effect is observed in the hydrogen bus subsidy scenario. • A long-term subsidy with low intensity is recommended. • Tradeoff between short- and long-term policy effects is identified and discussed. [ABSTRACT FROM AUTHOR]

This paper asks how legislative elites—lawmakers serving on statehouse committees with jurisdiction over transportation and energy—set transportation policy and funding agendas and what factors matter for compelling lawmaker policy action or explaining inaction. The role of legislatures in federalist systems has broader implications for the setting of transportation policy agendas, but in this study, we focus on U.S. state legislatures. We report on five focus group discussions conducted with 23 legislative representatives from 19 different states to reveal untapped insights into committee members' perceptions and the factors that drive their attention to certain issues in contemporary U.S. transportation policy. We find that these state-level political elites almost universally see funding as the most important issue and recognize the sector's broad fiscal reliance on motor fuel taxes as structurally unsound, given growing vehicle fuel efficiency and electric vehicle adoption. We find further that, with respect to their own policymaking activities, state lawmakers understand transportation policy and energy transition as distinct issues and appear unable to meet these known challenges by crossing committees to redesign policy. We also see implications of these results more broadly for subnational and provincial governments that, regardless of country setting, must often work across multiple layers of government to set policy agendas in the context of an evolving energy and transportation landscape and that warrant greater attention from policy scholars. [ABSTRACT FROM AUTHOR]

To meet the projected increase in global demand for energy while tackling sustainability concerns, the widespread adoption of renewable energy is inevitable. Once harnessed, exports of this renewable energy from regions with excess resources are anticipated to those that will require imports of energy. The shipping sector will thus play a pivotal role in enabling such trade through energy carriers such as hydrogen, ammonia, methanol, and liquid organic hydrogen carriers. Furthermore, in addition to these energy carriers, carbon dioxide is also expected to become an important maritime trade commodity to achieve climate targets. Through the deployment of carbon capture utilization and storage, and more recently, negative emission technologies, carbon dioxide will need to be transported to regions with the appropriate infrastructure and resources necessary for their anticipated implementation. Presently, in light of these circumstances, the lack of experience in shipping a number of these energy carriers and carbon dioxide must be addressed. As such, an understanding of the techno-economic and environmental feasibility of the large-scale shipping of these commodities must be established at all scales of operation. Accordingly, this work proposes the use of process systems engineering based approaches to enable the marine transportation of these future energy carriers and carbon dioxide from a multi-scale perspective. To lay the foundation in support of this initiative, a framework that considers the multiple scales involved is then presented for the design and operation of progressive ships and their supply chains as part of a decarbonized energy system. [Display omitted] • Discussed the potential of shipping energy carriers and carbon in achieving climate targets. • Identified feasibility challenges surrounding the large-scale shipping of hydrogen carriers. • Proposed a multi-scale framework for the design of ships and supply chains. [ABSTRACT FROM AUTHOR]

Hydrogen exploration in the municipality of Maricá (Rio de Janeiro State, Brazil) indicates that important hydrogen and helium gas fluxes are emitted through reactivated faults. The gas concentrations in the soils, and the modelled gas fluxes, are among the most intense measured so far in the world. This exploration has shown new surface expression of hydrogen micro-seeps, observed along reactivated large tectonic accidents instead of "fairy circles", most common proxy for hydrogen systems in cratonic formation. The geology of Maricá, consisting in Neoproterozoic metamorphic rocks without any already documented evidence of hydrogen-prone formations, appears as a very new field of investigation for natural hydrogen. Results indicate the presence of systematic hydrogen saturation of the usual detectors plugged at 80 cm depth, as well as a permanent recharge of hydrogen through time, without relaxation time. Moreover, positive helium anomalies are associated with this hydrogen soil gas, proving the existence of a gas flux coming from deep horizons of the subsurface. This reduces the risk of misinterpretation of surface hydrogen measurement, since the fear of drill bit metamorphism or superficial biological activity inducing hydrogen artefacts is always a possibility. These hydrogen and helium micro-seeps are associated with positive thorium concentration superficial anomalies, as it was already observed in other places associated with hydrogen exudations. We present a model of soil gas behavior, with a differential process of adsorption/desorption of each gas compound (N 2 , O 2 , Ne, H 2 and He), associated with a deep flux of hydrogen and helium. It is possible to assess a quantification of hydrogen flux of 0.32 m3 m−2.day−1. The surface flux ratio He/H 2 is much higher than any published value of generative flux. This may be explained by a subsurface accumulation, where hydrogen is severely altered whereas helium is preserved, increasing the relative proportion of helium versus hydrogen. [Display omitted] • The Marica municipality (Brazil) reveals important potential for natural hydrogen. • Reactivated faults are excellent proxies for natural hydrogen exploration. • Hydrogen seeping out of reactivated faults may be larger than in fairy circles. • Association of hydrogen and helium in soils indicates that no artefact concerns the hydrogen measurements in soils. • Metamorphic formations may be excellent candidates for hydrogen exploration. [ABSTRACT FROM AUTHOR]

Hydrogen-fuelled technologies for home heating and cooking may provide a low-carbon solution for decarbonising parts of the global housing stock. For the transition to transpire, the attitudes and perceptions of consumers must be factored into policy making efforts. However, empirical studies are yet to explore potential levels of consumer heterogeneity regarding domestic hydrogen acceptance. In response, this study explores a wide spectrum of consumer responses towards the prospect of hydrogen homes. The proposed spectrum is conceptualised in terms of the 'domestic hydrogen acceptance matrix', which is examined through a nationally representative online survey conducted in the United Kingdom. The results draw attention to the importance of interest and engagement in environmental issues, knowledge and awareness of renewable energy technologies, and early adoption potential, as key drivers of domestic hydrogen acceptance. Critically, strategic measures should be taken to convert hydrogen scepticism and pessimism into hope and optimism by recognising the multi-dimensional nature of consumer acceptance. To this end, resources should be dedicated towards increasing the observability and trialability of hydrogen homes in proximity to industrial clusters and hubs, where the stakes for consumer acceptance are highest. Progress towards realising a net-zero society can be supported by early stakeholder engagement with the domestic hydrogen acceptance matrix. • Domestic hydrogen acceptance entails a spectrum of multi-dimensional responses. • Interest and engagement in environmental issues enhances hydrogen acceptance. • Knowledge and awareness of renewables promotes hydrogen optimism. • Consumer innovativeness is associated with support for hydrogen homes. • Consumer-orientated research can help steer the domestic hydrogen transition. [ABSTRACT FROM AUTHOR]

Subsurface porous rocks hold significant hydrogen (H 2) storage potential to support an H 2 -based energy future. Understanding H 2 flow and trapping in subsurface rocks is crucial to reliably evaluate their storage efficiency. In this work, we perform cyclic H 2 flow visualization experiments on a layered rock sample with varying pore and throat sizes. During drainage, H 2 follows a path consisting of large pores and throats, through a low permeability rock layer, substantially reducing H 2 storage capacity. Moreover, due to the rock heterogeneity and depending on the experimental flow strategy, imbibition unexpectedly results in higher H 2 saturation compared to drainage. These results emphasize that small-scale rock heterogeneity, which is often unaccounted for in reservoir-scale models, plays a vital role in H 2 displacement and trapping in subsurface porous media, with implications for efficient storage strategies. [Display omitted] • Pore-scale heterogeneity impacts H 2 flow and trapping in sandstones. • Flow direction has a pronounced effect on H 2 trapping in heterogeneous rocks. • Understanding small-scale rock heterogeneity is crucial to build reservoir models. [ABSTRACT FROM AUTHOR]

The article deals with the issue of modern challenges in the development of the fuel and energy complex, including the oil and gas industry as its basis in terms of the volume of tax revenues to the budget. Industry technological priorities have been identified: the creation of domestic equipment and technologies for the traditional upstream fuel and energy complex, digital transformation and the development of Industry 4.0 technologies, the development of technological competencies in key areas of energy transition, and the development of technologies in terms of ecology and industrial safety. The world experience of supporting the development of scientific research in industry is analyzed on the example of the USA, Norway and China. An analysis of the challenges of the institutional development of the fuel and energy complex at all stages from research to serial production is presented. The covenants of the state in the field of developing human resources for the implementation of the energy transition of the domestic fuel and energy complex, independent of external circumstances, have been determined. Proceeding from the analysis of internal barriers and successful international practices, proposals were made for the development of state technology policy. The National Program of the Russian Federation formulates directions for the development of the industry in the medium term. The technological development of the Russian Federation in the medium term will be influenced, on the one hand, by a number of external and internal threats of technological backwardness and degradation of the Russian economy, and on the other, by emerging new opportunities. Russia has a serious scientific and technical foundation in the field of hydrogen energy, scientific and technical personnel, operating facilities in the hydrogen industry, intellectual property, standard base, design and operational documentation, experience in creating the world's largest hydrogen filling station for launch vehicles and spacecraft ("Energy- Buran") guarantee the successful completion of assigned tasks in the medium term. Huge reserves of biomass, hydro resources, wind resources, geothermal resources, wave energy of the seas and oceans, solar energy provide enormous opportunities for the export of hydrogen to all interested countries, as well as the widespread use of hydrogen in the national economy, primarily for converting aviation to environmentally friendly fuel and preserving the environment megacities and large urban agglomerations. [ABSTRACT FROM AUTHOR]

The transition to increasingly renewable electricity grids and the electrification of industrial processes are two recent developments promising to be potential solutions towards net zero in industrial production processes. Generally, grid electricity is perceived as a stable and reliable resource that can be accessed on demand. However, that is not always the case for large industrial users (100 MW+), and a key future challenge that must be overcome is the inherent uncertainty of the electricity supply by renewable sources, as well as in pricing. In methanol production, the concept of using electrolysis and CO2 capture is being explored as a way of replacing reforming to produce syngas for "green" methanol production. With the omission of the reforming process which supplies energy as steam for the process, there is now a need to electrify the affected downstream unit operations. Distillation is a key unit operation in chemical operations that consumes large amounts of energy for reboiler duty and holds the key to making on-specification AA-grade methanol, a precursor chemical. With the volatility of the electricity market, hence supply, these columns must be able to withstand a sudden large reboiler duty drop. This paper developed a novel process operations and control principle to allow for the flexible operation of a high-purity methanol distillation column in volatile energy markets. At its core is the concept of using a distillation column as a "process battery". Results obtained from a validated process simulation show that the novel "process battery" operations principle can withstand a supply-side change as great as 75% within a time span of 5 min without breaking complex quality and performance specifications of the column. This control philosophy is a major departure from the traditional process control and operating regimes that are focused on maintaining steady operations under all conditions. • Novel control philosophy developed for flexible operation of high-purity methanol distillation in volatile energy markets. • A major change from traditional operations and control focused on maintaining steady operations under all conditions. • The concept of using a distillation column as a "process battery" is defined. • Validated process simulation results show the strategy withstands large supply-side changes without breaking specifications. [ABSTRACT FROM AUTHOR]

• Examine the effect of corruption, income inequality and redistribution on energy mix. • Income inequality reduces renewable energy demand and increases nonrenewable demand. • Income redistribution increases renewable energy demand and decreases nonrenewable demand. • Control of corruption increases renewable and nonrenewable energy consumption. • Reducing income inequality and corruption is key for hastening renewable energy transition. This study examines the impact of corruption, income inequality, and redistribution on energy consumption (renewable, nonrenewable, and total) in 166 countries. Panel data and the two-step dynamic system-generalized method of moments techniques are utilised. Our findings show that net (post-tax/transfer Gini index) and market (pre-tax/transfer Gini index) income inequality reduce total energy and renewable energy consumption while increasing nonrenewable energy consumption. The results indicate that income redistribution drives total energy and renewable energy consumption while decreasing nonrenewable energy use. The study highlights that control of corruption increases total energy, renewable, and nonrenewable energy consumption. Moderation and marginal effect analysis suggest that when control of corruption increases, income inequality increases total energy, nonrenewable, and renewable energy consumption. Again, when corruption is effectively controlled, income redistribution increases renewable energy consumption while reducing nonrenewable energy consumption. These findings differ amongst regions. Following these findings, we recommend that policymakers should focus on reducing corruption and addressing income inequality through redistribution policies to accelerate the transition towards a renewable energy economy. [ABSTRACT FROM AUTHOR]

[Display omitted] • Investigated the impact of climate-tech and energy transition on CO 2 emissions. • Role of environmental regulations is also considered. • Climate-tech and energy transition improves the environmental quality. • Environmental regulations are negatively associated with CO 2 emissions. • Policies are proposed to promote sustainable development in EU countries. The transition from conventional energy to clean energy is the ultimate strategy to reduce global CO 2 emissions. In this regard, climate technologies (climate-tech) can pave the way toward achieving the capabilities required to promote alternative energy and energy saving. In addition, environmental regulations can support technological upgrading, energy transition, and emissions reduction to promote sustainable development. With this in view, this study investigates the impact of climate technologies (climate-tech) and energy transitions on CO 2 emissions in the European Union (EU) member countries. Further, we examine the role of environmental regulation in the relationship between climate-tech, energy transition, and CO 2 emissions. The empirical analysis is conducted based on international panel data for 26 EU countries ranging from 1994 to 2019, and the Common Correlated Effects Mean Group (CCE-MG) method is employed to estimate the coefficients of the variables. The outcomes of the analysis indicate that both climate-tech and energy transitions mitigate environmental degradation by reducing carbon emissions. Additionally, environmental regulations are found to be an effective monitoring and controlling tool that can significantly reduce CO 2 emissions. Moreover, economic growth and urbanization as control variables contribute to increasing CO 2 emissions, thus negatively affecting environmental sustainability. The causal analysis demonstrates that decision-making trends related to climate-tech, energy transition, and environmental regulations influence CO 2 emissions. Conversely, strategies for coping with CO 2 emissions and climate change will affect energy transitions and environmental regulations. In light of these analytical findings, this paper proposes that EU countries should vigorously develop climate-related green technologies and actively promote the energy transition process along with the implementation of environmental regulations for sustainable development. [ABSTRACT FROM AUTHOR]

Researchers and policymakers are seeking alternatives to oil products. Hydrogen and electricity could be the answer. This review compares both carriers and their technologies across the production chain. This study indicates electricity is more mature and advanced on a large scale. It also presents greater Energy Returns on Investment (EROI) over hydrogen, which portends a viable alternative to oil products. Hydrogen is not adaptable to traditional uses and comes with significant transportation losses, so it's recommended as an energy storage option instead of a carrier. It is a competitive option in areas where grid extension is not feasible and is hard to abate industries. The primary resource of carriers is crucial for their energy and environmental sustainability. Therefore, clean energy and carbon capture and storage technologies and their hybridization across the production chain could define the future energy landscape. • Electricity present greater maturity, energy and environmental advantages. • Hydrogen is proposed as an energy storage medium rather than a carrier. • Energy source of alternatives critical determinant of sustainability. • Renewables, nuclear energy, CCS and technology hybrids define the future of energy. [ABSTRACT FROM AUTHOR]

The envisioned role for Türkiye in the context of Europe's energy strategies should be crucial. By promoting countries like Türkiye can contribute significantly to global efforts in advancing sustainable energy transitions. Moreover, Incorporating Türkiye into Europe's energy strategies can reduce reliance on external energy suppliers and enhance energy security. The findings of this study offer fresh perspectives on the intricacies of the energy system dynamics and make valuable contributions to the ongoing discourse surrounding transition routes. The study takes into account several key aspects, including the current state of hydrogen in Türkiye, the country's potential for renewable energy, the existing policy and regulatory framework, and the necessary infrastructure and market conditions required for the establishment of a hydrogen hub. These insights shed light on the feasibility and viability of hydrogen as an indispensable component within the context of Türkiye 's energy landscape, offering valuable guidance for policymakers, industry stakeholders, and researchers involved in shaping the future of the energy sector. • The envisioned role for Türkiye in the context of Europe's energy strategies. • Insights and perspectives on energy dynamics, enrich discourse on transition routes. • EU-Türkiye green Hydrogen collaboration overcomes political setbacks, forging a transformative alliance. • Türkiye has the potential to seize a significant market share and enhance the value of its expansive territory. • Türkiye and Europe can develop clean energy by transporting pure hydrogen or blending it with natural gas. [ABSTRACT FROM AUTHOR]

The global imperative to transition from fossil fuels to renewable sources is addressed, with hydrogen identified as a pivotal energy carrier. Departing from qualitative approaches, quantitative methodologies are employed to understand the challenges comprehensively. Qualitative insights are quantitatively assessed through a novel index, enabling a nuanced analysis of strengths and weaknesses. The resulting model is a precise tool for informed decision-making in energy transition efforts. Notably, Chile, New Zealand, and Morocco are identified as high-potential economies for hydrogen development, aligning with expert opinions. Conflict demonstrates an overall negative correlation with technological progress, while regulatory quality emerges as a strong positive correlation with the state of hydrogen in policy. This quantitative model offers a robust framework for future research and application, including incorporating additional data and subnational-level analysis. The study provides a quantitative foundation for advancing hydrogen development and sustainable energy transition. • A numerical index can be beneficial to studying the ongoing energy transition. • We present a novel way of quantizing hydrogen development using various indicators. • Results show that there are several "hidden champions" with high growth potential. • Indicators based on varying dimensions of development offer a clear picture forward. [ABSTRACT FROM AUTHOR]

In response to the pressing need for sustainable and greener energy alternatives, this study investigates into the exploration of hydrogen energy as a promising solution. The purpose of this study is to identify the common challenges and potential solutions in hydrogen energy transition and to validate their applicability in Malaysia through expert interviews. This research utilizes various methods: literature review identifies challenges and solutions, bibliometric analysis validates findings, and interviews with Malaysian hydrogen experts validate their applicability for the country. Thematic coding analysis using NVivo software is used to analyse the interview data. From this study, top three challenges are identified as the most applicable in Malaysia: high cost, ambiguous policy and limited infrastructure. Additionally, three potential solutions are considered as the most relevant: establishment of clear policy, encouragement of public-private partnerships, as well as investment in technologies and infrastructure. [ABSTRACT FROM AUTHOR]

Social entrepreneurship plays a crucial role in global sustainable development, enhancing the quality of life and preserving environmental, human, and social capital. However, when it comes to the energy transition, it faces numerous challenges and experiences conflicts in terms of costs, technological innovation, and public policies. This study seeks to illustrate one of the new alternative energy schemes which could replace fossil fuels in the future: hydrogen. This transformation would result in significant social impacts, leading to the question, "how should it be done?" Social entrepreneurship can integrate socio-economic actors and agents and help them to devise and implement new forms of energy innovation. Therefore, a descriptive qualitative methodology was implemented, that allows us to analyze the process of building entrepreneurship with a social vision and to propose a model that enables the transition from fossil economies to the hydrogen economies. Among the most significant results, the importance of the support of the three primary axes of each country and the role of social entrepreneurship as a key element for the transition stand out. The discussion contributes to the debate on the path that academia should lead, and the fundamental role of entrepreneurship based on social conscience as a driver of change. • Hydrogen can replace fossil fuels and reduce emissions. • Proposed model for Hydrogen transition with key role of social entrepreneurship. • Academia's role in social entrepreneurship as driver for change, redefining entrepreneurship to meet societal needs. [ABSTRACT FROM AUTHOR]

Water Flooding (WF) and CO 2 Foam Flooding EOR (CFF) processes are exergy intensive and CO 2 emissive in nature. Hence, the objective of this work is to investigate the ways to attain decarbonization and to evaluate hydrogen requirement for attaining energy transition during WF and CFF processes under different operational conditions. This was performed by using exergy-based evaluation metrics (i.e., Exergy-Return on Exergy-Investment (ERoEI), carbon emissions and hydrogen intensity). It was found that CFF process was 1.69 times more exergy intensive than WF process. Further, for every barrel of oil produced, WF process had net-CO 2 emission of 5.18 kg, while CFF process had net-CO 2 sequestration of 814.5 kg. Moreover, during CFF process, reducing the surfactant concentration from 2.5 wt% to 0.5 wt% had correspondingly decreased CO 2 emissions from 70% to 31%. Further, to attain energy transition during production operations, it was evaluated that WF process requires 1.7 times more hydrogen than CFF process. [Display omitted] • Decarbonization & energy transition was carried out on CO 2 foam flooding EOR process. • Performed sensitivity analysis on various field operations using evaluation metrics. • Manufacturing of surfactants & Injection pumps consumed 66% of total exergy invested. • By using H 2 as fuel source in field operations, the CO 2 emissions are reduced by 62%. • CO 2 foam flooding EOR process sequestrated 27 times more mass of CO 2 than it emitted. [ABSTRACT FROM AUTHOR]

This study investigated the impact of cushion gas type and presence on the performance of underground hydrogen storage (UHS) in an offshore North Sea aquifer. Using numerical simulation, the relationship between cushion gas type and UHS performance was comprehensively evaluated, providing valuable insights for designing an efficient UHS project delivery. Results indicated that cushion gas type can significantly impact the process's recovery efficiency and hydrogen purity. CO 2 was found to have the highest storage capacity, while lighter gases like N 2 and CH 4 exhibited better recovery efficiency. Utilising CH 4 as a cushion gas can lead to a higher recovery efficiency of 80%. It was also determined that utilising either of these cushion gases was always more beneficial than hydrogen storage alone, leading to an incremental hydrogen recovery up to 7%. Additionally, hydrogen purity degraded as each cycle progressed, but improved over time. This study contributes to a better understanding of factors affecting UHS performance and can inform the selection of cushion gas type and optimal operational strategies. • Compositional numerical simulation of underground hydrogen storage in a North Sea aquifer utilising CMG-GEM. • Hydrogen recovery efficiency improves with the utilisation of cushion gas. • CO 2 exhibits highest storage capacity; N 2 and CH 4 improve recovery efficiency. • CH 4 as cushion gas leads to 80% recovery efficiency, minimizing lateral spreading and viscous fingering. • Cushion gas density dictates the efficiency of the underground hydrogen storage scheme. [ABSTRACT FROM AUTHOR]

This study presents a systematic workflow for estimating hydrogen storage capacity for a smooth energy transition from natural gas market to hydrogen market to achieve net-zero emissions. The workflow establishes maximum and minimum thresholds for hydrogen storage and considers appropriate storage techniques, including underground or surface facilities. The technique assesses environmental footprint of each storage technique and evaluates associated emission reductions. We apply this workflow to energy market in Alberta and project minimum and maximum storage thresholds of 0.28 and 5 megatonne/year (Mt/year) by 2050. Under three distinct storage scenarios, the storage capacity necessitates 128 salt caverns, 10 million compressed gas tanks, or 78,150 cryogenic liquefied tanks. Salt cavern storage emerges as a promising choice owing to its relatively lower emissions of 0.16 MtCO 2 e/year and a land footprint of 2.56 km2. The net emission reduction achieved is 1.47 MtCO 2 e/year, equivalent to 0.8% of Canada's target emission reduction of 190 MtCO 2 e/year by 2050. • A workflow is developed to forecast required hydrogen storage capacity in Alberta. • Salt caverns emerge as a reliable and practical technique for large-scale hydrogen storage. • The workflow projects the required number of salt caverns for hydrogen storage. • Supplying stored hydrogen to market reduces 1.5 megatonne/year of GHG emissions. [ABSTRACT FROM AUTHOR]

In aiding India's effort to become carbon neutral, this research focusses on its Southeastern (SE) region, investigating its potential for decarbonization and using of green hydrogen as alternate fuel for industrial operations. The study analyzed the total CO 2 emissions from the power and industrial sectors in the region, and estimated an annual emissions of 307.8 million tonnes. Considering different GDP growth scenarios, this study estimated the demand for energy and green hydrogen until 2050 for achieving energy transition. Based on the region's renewable energy capacity, an optimal energy mix of 5% small hydro, 45% wind and 50% solar power is recommended for green hydrogen production. This study found that the Cauvery and Krishna-Godavari basins have the storage potential to continuously deliver the stored hydrogen for seven years to the region, ensuring energy security. Finally, by decarbonizing industrial operations in SE region, the global temperature rise could be reduced by 0.003842 °C. [Display omitted] • Power plants are the leading CO 2 emitters, contributing to 64% of total CO 2 emissions. • Energy demand projected till 2050, with Andhra Pradesh as leading consumer. • Quantified green hydrogen and solar energy demand to achieve energy transition. • Hydrogen storage capacity of Cauvery and KG basins for energy security are assessed. • Cauvery and KG basins can potentially deliver the stored H 2 continuously for 6 years. [ABSTRACT FROM AUTHOR]

The transition to a low-carbon energy system can be depicted as a "great reconfiguration" from a socio-technical perspective that carries the risk of impact shifts. Electrification with the objective of achieving rapidly deep decarbonisation must be accompanied by effective efficiency and flexibility measures. Hydrogen can be a preferred option in the decarbonisation process where electrification of end-uses is difficult or impractical as well as for long-term storage in energy infrastructure characterised by a large penetration of renewable energy sources. Notwithstanding the current uncertainties regarding costs, environmental impact and the inherent difficulties of increasing rapidly supply capacity, hydrogen can represent a solution to be used in multi-energy systems with combined heat and power (CHP), in particular in urban energy districts. In fact, while achieving carbon savings with natural gas fuelled CHP is not possible when low grid carbon intensity factors are present, it may still be possible to use it to provide flexibility services and to reduce emissions further with switch from natural gas to hydrogen. In this paper, a commercially established urban district energy scheme located in Southampton (United Kingdom) is analysed with the goal of exploring potential variations in its energy demand. The study proposes the use of scalable data-driven methods and probabilistic simulation to generate seasonal energy demand patterns representing the potential short-term and long-term evolution of the energy district. • Hydrogen role in the transition to low carbon energy systems for urban energy district. • Data-driven urban energy modelling using regression-based approaches. • Probabilistic modelling of energy demand in terms of electricity and fuels. • Climate change impact and energy efficiency measures accounting. • Seasonal variations of energy demand patterns from short-term to long-term scenarios. [ABSTRACT FROM AUTHOR]

Large-scale hydrogen underground storage is widely considered as an important solution for energy transition to mitigate global warming, however, our understanding on the various chemical and physical processes leading to H 2 loss during geo-storage remains largely unknown. We conducted adsorption isotherms measurements of H 2 , CH 4 and CO 2 on Cretaceous Cameo coal at 35, 50 and 65 °C, to explore adsorption mechanisms of H 2 and deciphering the effect of cushion gas (e.g., CH 4 , CO 2) on H 2 loss in the subsurface. The adsorbed amounts of H 2 are just 12% and 6% of CH 4 and CO 2 at temperature of 35 °C and pressure of 2.3 MPa, respectively, and H 2 adsorption behavior on Cameo coal can be described well by Langmuir monolayer theory. The extremely high Langmuir pressures (35–49 MPa) for H 2 indicate very weak affinity with coal, compared to CH 4 and CO 2. Differences of Langmuir adsorption capacities suggest that the gas adsorption of H 2 and CH 4 are mainly by physical interactions while both physical and chemical bonding with coal structures occurs for CO 2. The affinity with solid materials for the three gases can be quantitatively evaluated by the heat of adsorption, which was determined to be ∼9.2 kJ/mol for H 2. Extrapolation of our experimental results to natural coal seams indicates that H 2 presents much smaller adsorption amounts at depth up to 2000 m, corresponding to temperatures lower than 65 °C and pressure less than 30 MPa, geological conditions that are suitable for hydrogen underground storage. This study confirms that the injection of CH 4 or CO 2 as cushion gas can largely reduce the H 2 loss by adsorption in the subsurface. Empirical calculation suggests H 2 adsorption will be insignificant with chemical composition of CH 4 above 8% or CO 2 above 2% at the storage sites (e.g., abandoned mines, depleted coal seams). Our study lays a foundation on the understanding of the risk of H 2 loss in large-scale hydrogen underground storage. • Adsorbed amounts of H 2 are much smaller than CH 4 and CO 2. • Weak affinity of H 2 with coals is quantitatively evaluated. • H 2 loss by adsorption during geological storage can be significantly reduced by the injection of CH 4 or CO 2 as cushion gas. [ABSTRACT FROM AUTHOR]

Underground hydrogen storage (UHS) in aquifers, salt caverns and depleted hydrocarbon reservoirs allows for the storage of larger volumes of H 2 compared to surface storage in vessels. In this work, we investigate the impact of aquifer-related mechanisms and parameters on the performance of UHS in an associated North Sea aquifer using 3D numerical compositional simulations. Simulation results revealed that the aquifer's permeability heterogeneity has a significant impact on the H 2 recovery efficiency where a more homogenous rock would lead to improved H 2 productivity. The inclusion of relative permeability hysteresis resulted in a drop in the H 2 injectivity and recovery due to H 2 discontinuity inside the aquifer which leads to residual H 2 during the withdrawal periods. In contrast, the effects of hydrogen solubility and hydrogen diffusion were negligible when studied each in isolation from other factors. Hence, it is essential to properly account for hysteresis and heterogeneity when evaluating UHS in aquifers. • Numerical compositional simulation utilising CMG-GEM of underground hydrogen storage in a North Sea aquifer. • Hydrogen recovery efficiency improves as the storage cycles increase. • Heterogeneity and hysteresis are the most impactful mechanisms on underground hydrogen storage. • Hydrogen solubility and diffusion in water have a minimal impact on the storage process when studied separately. • Solubility and diffusion effects become more pronounced when studied in combination with each other and hysteresis. [ABSTRACT FROM AUTHOR]

As energy system research into high shares of renewables has developed, so have the perspectives of the fundamental nature of a highly renewable economy. Early energy system transition research suggested that current fossil fuel energy systems would transition to a 'Hydrogen Economy', whereas more recent insights suggest that a 'Power-to-X Economy' may be a more appropriate term, as renewable electricity will become both the most important primary and final energy carrier through various Power-to-X conversion routes across the energy system. This paper provides a detailed overview on research insights of recent years on the core elements of the Power-to-X Economy and the role of hydrogen based on latest research results. These results suggest that, by 2050, upwards of 61,737 TWh LHV of hydrogen will be required to fully defossilise the global energy-industry system. Hydrogen, therefore, emerges as a central intermediate energy carrier and its relevance is driven by significant cost reductions in renewable electricity, especially of solar photovoltaics and wind power. Efficiency and cost drivers position direct electrification as the primary solution for defossilisation of the global energy-industry system; however, electron-to-molecule routes are essential for the large subset of remaining energy-related demands including chemical production, marine and aviation fuels, and steelmaking. [Display omitted] • The term 'Hydrogen Economy' insufficiently describes future energy systems. • 'Power-to-X Economy' better highlights the essential role of renewable electricity. • The highest reported demand for e-hydrogen is presented at over 60 PWh H2,LHV. [ABSTRACT FROM AUTHOR]

Green hydrogen offers a promising solution to energy transition challenges. However, a comprehensive understanding of its scenario in Brazil is lacking, hampering the formulation of strategies to enhance domestic market competitiveness. This article identifies Brazil's panorama of green hydrogen, the barriers, drivers, and investment potential for developing this market. It also proposes strategies to stimulate the growth of this industry at the national level. Based on qualitative methods, including literature analysis and interviews with 17 experts, the study reveals that regulatory and political issues and infrastructure readiness necessitate collaborative efforts between the public and private sectors. Overcoming technical hurdles like cost-effective large-scale production and efficient storage demands research investments. Challenges like high production costs and an underdeveloped national industry impede market expansion. By fostering players' collaboration, Brazil could harness its potential in the green hydrogen sector, promoting economic growth, job creation, and environmental sustainability to attain a global leadership position. • The panorama of green hydrogen in Brazil was presented. • Barriers that limit the development of the green hydrogen chain were analyzed. • Strategies to strengthen the green hydrogen market were presented. • Reasons for investing in green hydrogen in Brazil were discussed. • Brazil can become one of the leading exporters of green hydrogen. [ABSTRACT FROM AUTHOR]

Green hydrogen potential as a clean energy carrier presents promising prospects in the fight against climate change. The most efficient method of producing decarbonized hydrogen is through electrolysis, which involves splitting water molecules using renewable sources of electricity. Morocco boasts various advantages that enable it to play a pivotal role in bringing this vision to fruition. Lately, the nation has devised an ambitious strategy for green hydrogen and implemented significant changes related to industry and water resource management. This document presents a thorough examination of Morocco's energy sector, with a special focus on the substantial hurdles that must be surmounted to establish an economy centered on green hydrogen, with the capacity to generate employment opportunities and achieve carbon neutrality. Numerous impediments require cooperation with Europe and other international allies to establish a green hydrogen industry in Morocco. These challenges encompass bolstering the competitiveness of green hydrogen, scaling up production, and cultivating the requisite expertise. • Morocco is identified as one of the countries with the highest potential for green hydrogen export. • Green hydrogen roadmap for Morocco is presented and analyzed. • Technological, economical, environmental and societal challenges for green hydrogen development in Morocco are outlined. [ABSTRACT FROM AUTHOR]

Hydrogen, as a carbon-free energy carrier, has emerged as a crucial component in the decarbonization of the energy system, serving as both an energy storage option and fuel for dispatchable power generation to mitigate the intermittent nature of renewable energy sources. However, the unique physical and combustion characteristics of hydrogen, which differ from conventional gaseous fuels such as biogas and natural gas, present new challenges that must be addressed. To fully integrate hydrogen as an energy carrier in the energy system, the development of low-emission and highly reliable technologies capable of handling hydrogen combustion is imperative. This study presents a ground-breaking achievement - the first successful test of a micro gas turbine running on 100% hydrogen with NOx emissions below the standard limits. Furthermore, the combustor of the micro gas turbine demonstrates exceptional fuel flexibility, allowing for the use of various blends of hydrogen, biogas, and natural gas, covering a wide range of heating values. In addition to a comprehensive presentation of the test rig and its instrumentation, this paper illuminates the challenges of hydrogen combustion and offers real-world operational data from engine operation with 100% hydrogen and its blends with methane. • Hydrogen's potential as an alternative, carbon-free fuel for micro gas turbines is assessed. • The obstacles of utilizing hydrogen fuel in a micro gas turbine are addressed and the necessary modifications are presented. • Data from successful tests of a micro gas turbine running on hydrogen blends ranging up to 100% hydrogen is presented. • NOx emissions below the standard limits were achieved with the new setup. • The study's outcomes could aid researchers and developers in incorporating hydrogen as a carbon-free energy carrier. [ABSTRACT FROM AUTHOR]

Argentina has a wide availability of renewable resources, which provides important advantages for the hydrogen vector incorporation. The province of Córdoba is an excellent model case for the study of the rapid incorporation of hydrogen as fuel, to replace 20% V/V of natural gas consumed in vehicular use. This does not involve major changes in infrastructure or modifications to the vehicles. This paper computes and analyzes the levelized cost of hydrogen with the emissions associated for each part of the complete hydrogen supply chain. Two different production sources were used: renewable energies sources and the Argentine electrical grid; and two production pathways: in situ and centralized production. Comparing the same volume of proposed hydrogen compressed natural gas and current CNG, a cost decrease in the majority of the scenarios and a CO 2 eq emission reduction ranging from 19.5 to 8.2% are achieved, even if the hydrogen is produced using the carbon-intensive grid electricity. • The Production of hydrogen to replace part of the CNG used in vehicles is proposed. • Levelized cost of hydrogen and the emissions associated was assessed. • The study includes the entire supply chain from production to the filling station. • The use of HCNG results in a reduction of emissions in all the studied scenarios. • The new fuel is economically favorable, becoming relevant for rapid energy transition. [ABSTRACT FROM AUTHOR]

When developed countries invest in developing countries there is often a trade-off between economic growth and environmental quality, but is this inevitable? Previous studies have concluded that one consequence of Foreign Direct Investment (FDI) is the transfer of polluting industries. However, there has been insufficient analysis of the pollutant consequence of this investment, as this may arise from the lack of renewable energy infrastructure to satisfy peaked energy demand. Using data from 17 developing countries from 2000–2020, this study undertakes an in-depth analysis of the effects of FDI and Private Participation in Energy Infrastructure (PPEI) investment on economic growth, pollution, and energy transition using a Seemingly Unrelated Regression model. The results reveal that FDI increases pollution and non-renewable energy consumption but, conversely, PPEI promotes energy transition, potentially mitigating the polluting impact of FDI. Developing countries can pursue long-term environmentally-sustainable economic growth by attracting private investment in their energy infrastructure. [ABSTRACT FROM AUTHOR]

Electric vehicles have penetrated the Dutch market, which increases the potential for decreased local emissions, the use and storage of sustainable energy, and the roll-out and use of electric car-sharing business models. This development also raises new potential issues such as increased electricity demand, a lack of social acceptance, and infrastructural challenges in the built environment. Relevant stakeholders, such as policymakers and service providers, need to align their values and prioritize these aspects. Our study investigates the prioritization of 11 Dutch decision-makers in the field of public electric vehicle charging. These decision-makers prioritized different indicators related to measurements (e.g., EV adoption rates or charge point profitability), organization (such as fast- or smart-charging), and developments (e.g., the development of mobility-service markets) using the best-worst method. The indicators within these categories were prioritized for three different scenario's in time. The results reveal that priorities will shift from EV adoption and roll-out of infrastructure to managing peak demand, using more sustainable charging techniques (such as V2G), and using sustainable energy towards 2030. Technological advancements and autonomous charging techniques will become more relevant in a later time period, around 2040. Environmental indicators (e.g., local emissions) were consistently valued low, whereas mobility indicators were valued differently across participants, indicating a lack of consensus. Smart charging was consistently valued higher than other charging techniques, independent of time period. The results also revealed that there are some distinct differences between the priorities of policymakers and service providers. Having a systematic overview of what aspects matter supports the policy discussion around EVs in the built environment. • Stakeholders find different things important, but can somewhat agree charging techniques becoming more or less important. • Priorities will shift to sustainable charging and sustainable electricity use, taking into account peak demand management. • Our study found group differences between the priorities of policymakers and the priorities of EV service providers. [ABSTRACT FROM AUTHOR]

The rapidly increasing production volume of clean hydrogen creates challenges for transport infrastructure. This study improves understanding of hydrogen transport options in Europe and provides more detailed analysis on the prospects for hydrogen transport in Finland. Previous studies and ongoing pipeline projects were reviewed to identify potential and barriers to hydrogen transport. A fatigue life assessment tool was built because material challenges have been one of the main concerns of hydrogen transportation. Many European countries aim at utilizing existing gas infrastructure for hydrogen. Conducted studies and pilot facilities have provided promising results. Hydrogen reduces the fatigue life of the pipeline, but existing pipelines can be used for hydrogen if pressure variation is maintained at a reasonable level and the maximum operation pressure is limited. Moreover, the use of existing pipelines can reduce hydrogen transport costs, but the suitability of every pipeline for hydrogen must be analyzed, and several issues such as leakage, leakage detection, effects of hydrogen on pipeline assets and end users, corrosion, maintenance, and metering of gas flow must be considered. The development of hydrogen transport will vary within countries depending on the structure of the existing gas infrastructure, and on the future hydrogen use profile. [Display omitted] • H 2 pipeline transportation projects in Europe were reviewed. • Use of linear elastic fracture mechanics fatigue assessment tool was demonstrated. • 80 bar natural gas pipeline could be converted to 45–55 bar H 2 pipeline. • Existing natural gas network will be utilized for H 2 transportation in the future. • Further research needed to ensure feasibility of H 2 transportation in existing grid. [ABSTRACT FROM AUTHOR]

This research investigates the influence of green technology innovation on the energy transition process using machine learning methods and econometric approach. To examine the effect of green technology innovation on the energy transition, we utilize panel data from China covering the years 2005–2020. The research intends to highlight the significance of green technology innovation in fostering the transition to sustainable energy. Our analysis of panel data reveals that green technology innovation significantly benefits China's energy transformation strategy. In particular, the study discovers that financial support for green technology innovation, as indicated by R&D spending and patent filings, has a favorable impact on the energy transition procedure. Additionally, to evaluate the influence of green technology innovation on the energy transition process, the research uses machine learning methods. The study emphasizes the need for increased investment in green technology innovation to support the transition to sustainable energy. Additionally, machine learning methods offer a valuable tool for evaluating how innovations in green technology affect the energy transition process. The research also sheds light on the variables that affect the outcome of energy transition initiatives, particularly emphasizing the role of R&D investments and patent filings in advancing a sustainable energy transition. • Investigates impact of green tech innovation on energy transition in China. • Panel data analysis reveals benefits of green tech investment. • R&D spending & patents have favorable impact on energy transition. • Study emphasizes need for increased investment in green tech. • Machine learning methods offer valuable tool for evaluating impact. [ABSTRACT FROM AUTHOR]

The majority of small district heating systems (DHS) in Poland are supplied with coal and do not have a status of efficient ones according to Energy Efficiency Directive. They should transform into efficient ones by taking an appropriate measures by the end of 2035. At the same time, a significant reduction of CO 2 emissions is expected in this sector. One of the possible solution for such systems is to apply unites fueled with fuels alternative to coal such as biomass. Cost benefits analysis of implementation a biomass ORC (Organic Rankine Cycle) cogeneration unit in municipal district heating system of 22 MW thermal capacity is the subject of the paper. The research included building configuration scenarios of a heat source regarding ORC size and operation modes. Different economic inputs such as electricity, fuel and European Union Allowance (EUA) for CO 2 prices as well as financial support mechanisms were considered. Economic indexes (Net Present Value, Internal Rate of Return and payback times) have been derived for both Polish and German conditions. [ABSTRACT FROM AUTHOR]

The number and importance of renewable energy communities (RECs) are increasing in all European countries due to the support of EU and national policies in order to foster the energy transition through participatory strategies for distributed energy systems. However, their development is rather slow in some countries, including Italy. The paper addressed the issue of the emergence of these socio-technical configurations in Italy, after the related law which entered into force in 2020 allowing the possibility of creating them. Our study focused on the alliances among different actors (professionals, institutions, NGOs, citizens) highlighting possible trends or models for the future that need to be confirmed in further research. The approach proposed to analyse this current process is the Actor-Network Theory, aiming at drawing the assemblages of human and non-human actants at a general level. Accordingly, we selected three case studies in order to show their different ways of organising, the relevance of trust in establishing each REC and the influence of local context on the composition and features of the actor-networks. [ABSTRACT FROM AUTHOR]

The Paris Agreement targets to halt the progression of climate change necessitate global cooperation and renewable energy uptake in developed and developing countries at similar rates. This study explores the energy transition pathway options for Egypt across the power, heat, transport, and desalination sectors as a representative case study for other emerging sunbelt economies. The LUT Energy System Transition Model has been used to investigate the feasibility of six scenarios, including four variations of best policy, delayed policy, and current policy scenarios. The least-cost solution, achieving 100% renewable energy and zero CO 2 emissions by 2050, is dominated by solar photovoltaics at 90% of the total primary energy demand. Key transition enablers are the excellent and low-cost solar resources, energy storage, and Power-to-X technologies allowing high electrification and full sector coupling. The results reveal that the current and delayed policy scenarios are the most expensive pathways, highlighting the value of leapfrogging into a fully renewable system. Such a transition would require policy reforms that balance investment risks in emerging economies and enable its financial mobilisation. The structural results of this study provide a reliable guide for energy transition planning in Egypt as well as other emerging sunbelt economies. [ABSTRACT FROM AUTHOR]

• Conversion of a DHN to diversified and decentralized renewable supply. • Fully physical digital twin of real DHN used to compare five renewable scenarios. • Implementation of up to 11 different generation and storage technologies at once. • Thermal energy storages with high charging/discharging power are essential. • Results show that at least 98 % renewable supply is possible. Due to the tremendous effects of climate change, the goal of a climate-friendly energy supply has developed into the main task of the energy sector. Today climate neutrality is a central issue at social, political and economic levels. It is a sector coupling issue, requiring renewable energies in electricity, mobility and heat supply. While the heat sector contributes the largest share to final energy demand of German municipalities, it is also the sector for which the path towards climate neutrality will be most challenging. This study presents pathways for large cities for the transition from fossil to renewable heat supply based on the example of Rostock. A detailed, fully-physical simulation model for Rostock's district heating was developed considering different potential heat sources including heat pumps, industrial and process heat, incineration of sewage sludge, waste and solid biomass as well as geothermal and solar thermal plants. Additionally, thermal energy storages have been integrated into the model. The study highlights the importance of simulation models in evaluating the feasibility of energy systems and emphasizes the need for incorporating detailed information in these models to obtain accurate results. Multiple scenarios have been investigated in order to analyse the interplay of heat generation, storage and the annual course of heat consumption. Five final concepts were derived meeting the requirement of climate-neutral heat supply. Although the results show that each variant has advantages and disadvantages, heat generators that make technical and economic sense in all cases were identified. The implementation of these is recommended. [ABSTRACT FROM AUTHOR]

Along with the popularity of the environment, social and governance (ESG) concerns, the circular economy concept has gained tremendous attraction from the industries, policy makers and academicians. On a firm level, this is implemented through the so-called Circular Business Model (CBM), which is seen through various initiatives. This includes firms in the energy industry, who are transitioning from conventional to renewable energy sources. Nevertheless, despite of the importance and the omnipresence of the practice, there is still lack of empirical research within the CBM topic. In particular, empirical research combining the CBM and technological innovation topic within energy industry (as technology-intensive and high risk industry) in developing country such as Indonesia, is still lacking. To answer this gap, using literature review as research method, this paper has arrived into the following propositions as main result; (1) there is a positive relationship between firm's level of CBM and technology innovation adoption to firm's performance, where (2) the two antecedents that are positively impacting firm's level of CBM and technology innovation adoption are leader's innovativeness and perceived level of technology. For academicians, this research is expected to provide contribution to the energy transition literatures within CBM and technology innovation adoption topic. Propositions provided in this paper is expected to serve as valuable basis in conducting further empirical research. For practitioners, this research is expected to provide valuable insights to make improvements and/or innovations in terms of business model, technology adoption, and strategy. At last, this research is expected to support energy transition. [ABSTRACT FROM AUTHOR]

• Without environmental regulation, Triple-B always relocates polluting industries. • Environmental regulation reduces the probability of relocation from 75 to 50%. • Higher customs duties reduce willingness of investors to take on investment risk. • Energy transition reduces the perceived level of punishment for polluters. • The current formula for applying carbon taxes must consider energy transition. Developed and developing countries have made remarkable efforts to address climate action. However, some developing countries have hung on to their comparative advantage in the polluting production of goods. By applying game theory, specifically a dynamic game with incomplete information, this study examines how the transfer of polluting industries can be discouraged by increasing associated costs through carbon taxes and custom duties on polluting imports. 24 developed countries and 18 developing countries were under analysis. The main findings suggest that energy transition could play a vital role in preventing this transfer. To attract clean FDI and boost energy transition, a stricter regulatory framework through levying carbon taxes and customs duties on polluting imports is recommended as an unstable regulatory framework may deter Foreign Direct Investment but also other desirable types of investment. Policymakers should reformulate how carbon taxes are applied to maintain their deterrent effect of reducing carbon emissions. [ABSTRACT FROM AUTHOR]

Meeting the European Commission's 'Fit for 55' climate goals by the year 2030 in the context of the trilemma of security of supply, environmental sustainability, and competitiveness will require concerted efforts from the Member States on all fronts. Among others, it will require optimised techno-economic solutions that offer sustainable decarbonisation pathways for the concurrent decarbonisation of many sectors of the economy. This paper attempts to provide empirical evidence of the 'rooftop solar PV+EV concept' efficacy as a promising pathway to decarbonise France's transport, power and building sectors concurrently. Using the System Advisor Model (SAM), we find that if rooftop solar PV is installed on half of the available roof space, and if half of the passenger vehicle owners replace their internal combustion engine vehicles (ICEVs) with EVs by 2030, then France can meet 20 %–42 % of total electricity demand in the three most populous cities. Moreover, the solar PV + EV coupling can reduce CO 2 emissions from passenger vehicle use and electricity generation by 43 %–48 %. Also, the coupling can be a potentially worthwhile investment with a payback period of 2–3 years, a levelised cost of energy (LCOE) of about €0.04/kWh, and a net present value (NPV) of €6–19 billion without a feed-in tariff. We analyse the potential implementation challenges of the 'rooftop solar PV + EV concept' and propose some solutions. Finally, we argue that coupling rooftop solar PV + EV in cities is a cost-effective strategy to decarbonise urban energy, transport and building sectors concurrently. Therefore, the government should consider enacting combined rooftop solar PV + EV decarbonisation policies that offer economic and environmental benefits. • Rooftop solar PV+EV can meet 20%-42% of electricity demand in France's three most populous cities. • Rooftop solar PV+EV can reduce CO 2 emissions from vehicle use and power generation by 43%-48%. • Coupling PV+ EV can be a potentially worthwhile investment with a payback period of 2-3 years, an LCOE of €0.04/kWh, and an NPV of €6-19 billion without a feed-in tariff. • Coupling rooftop solar PV+EV in cities is a cost-effective strategy to decarbonise urban energy, transport and building sectors. • The government should consider enacting PV+EV combined decarbonisation policies that can offer economic and environmental benefits. [ABSTRACT FROM AUTHOR]

This paper examines the relationship between urban form, residential rooftop solar PV potential, and levelized cost of electricity (LCOE) in high-income, middle-class, and low-income neighborhoods in Accra, Ghana. Using building footprint data, ArcGIS Pro, and linear regression analysis, we find a statistically significant association between urban form parameters (building density, neighborhood compactness, building footprint area, suitable rooftop area, and near distance between buildings) and the rooftop solar PV potential in all the three types of neighborhoods. However, the well-planned high-income neighborhood exhibited the highest rooftop solar PV potential with low LCOE values for most houses, while the lowest rooftop PV potential and highest LCOE values were found in the largely unplanned low-income neighborhood. The low-income neighborhood exhibited higher density with clustered building patterns and, consequently, lower rooftop PV potential. The LCOE ranged between $0.02/kWh-$0.19/kWh for most buildings, with 92 %, 74 %, and 51 % of houses in the high-income, middle-class, and low-income neighborhoods falling within this range, respectively. We conclude that while capital subsidies for residential solar PV can boost their uptake by urbanites, their effectiveness could be limited in low-income neighborhoods due to the limitations imposed by their urban form. It may be more appropriate for policy interventions to target such neighborhoods with community solar schemes while targeting high-income neighborhoods with building integrated solar photovoltaics. [Display omitted] • Rooftop solar PV potential is higher in high-income neighborhoods than in low-income ones. • Neighborhoods with low building density and dispersed layouts have higher solar PV potential. • Urban form could impede the diffusion of solar PV in cities. • Solar energy considerations need to be mainstreamed into urban planning and design. • Urban energy transition theories need to incorporate socio-spatial dimensions. [ABSTRACT FROM AUTHOR]

Substantial changes in the energy system are necessary to achieve greenhouse gas neutrality. Green hydrogen is a key to defossilisation. Politicians frequently mention the use of hydrogen in the building sector to supply decentrally produced heat as a potential field of application. An advantage repeatedly mentioned is that the existing gas distribution network infrastructure is an important asset that could still be used in the future. However, there is a lack of analyses of the conversion of gas distribution networks to hydrogen focussing on the economic implications on the costs of the distribution network infrastructure. The paper provides insights using a techno-economic model network analysis (MNA) tool called gas Distribution grId modelliNg tOol (DINO). The analysis is carried out for Germany and considers hydrogen use in all counties. The results are compared to a synthetic methane and electrification scenario. In the hydrogen scenario, the total need for distribution grids is decreasing until 2050 by at least 130,000 km. The network length of the synthetic methane scenario is slightly lower and that of the electrification scenario drops to zero. The annual operation costs are lower in all scenarios as gas demand and infrastructure are reduced. Nevertheless, the total annual cost in the hydrogen scenario is potentially two times higher than in the case of the synthetic methane scenario and more than four times higher than in the electrification scenario. Based on the present results, it is questionable whether an advantage of the continued use of the existing gas distribution grid infrastructure in case of synthetic gas or hydrogen scenarios exists. • Impact of the energy transition on gas distribution networks by comparing three defossilisation pathways. • Application of a model network analysis to the use of hydrogen to derive the cost-optimal gas distribution networks. • First nationwide analysis of hydrogen in gas distribution grids based on the German case at the county level. • Decreasing demand for gas distribution infrastructure in all scenarios and highest costs in the case of hydrogen use. • Questionable advantage of continued infrastructure use in case of conversion of existing gas distribution networks. [ABSTRACT FROM AUTHOR]