Hasil untuk "Energy industries. Energy policy. Fuel trade"

Steven J. Davis, N. Lewis, Matthew Shaner et al.

Path to zero carbon emissions Models show that to avert dangerous levels of climate change, global carbon dioxide emissions must fall to zero later this century. Most of these emissions arise from energy use. Davis et al. review what it would take to achieve decarbonization of the energy system. Some parts of the energy system are particularly difficult to decarbonize, including aviation, long-distance transport, steel and cement production, and provision of a reliable electricity supply. Current technologies and pathways show promise, but integration of now-discrete energy sectors and industrial processes is vital to achieve minimal emissions. Science, this issue p. eaas9793 BACKGROUND Net emissions of CO2 by human activities—including not only energy services and industrial production but also land use and agriculture—must approach zero in order to stabilize global mean temperature. Energy services such as light-duty transportation, heating, cooling, and lighting may be relatively straightforward to decarbonize by electrifying and generating electricity from variable renewable energy sources (such as wind and solar) and dispatchable (“on-demand”) nonrenewable sources (including nuclear energy and fossil fuels with carbon capture and storage). However, other energy services essential to modern civilization entail emissions that are likely to be more difficult to fully eliminate. These difficult-to-decarbonize energy services include aviation, long-distance transport, and shipping; production of carbon-intensive structural materials such as steel and cement; and provision of a reliable electricity supply that meets varying demand. Moreover, demand for such services and products is projected to increase substantially over this century. The long-lived infrastructure built today, for better or worse, will shape the future. Here, we review the special challenges associated with an energy system that does not add any CO2 to the atmosphere (a net-zero emissions energy system). We discuss prominent technological opportunities and barriers for eliminating and/or managing emissions related to the difficult-to-decarbonize services; pitfalls in which near-term actions may make it more difficult or costly to achieve the net-zero emissions goal; and critical areas for research, development, demonstration, and deployment. It may take decades to research, develop, and deploy these new technologies. ADVANCES A successful transition to a future net-zero emissions energy system is likely to depend on vast amounts of inexpensive, emissions-free electricity; mechanisms to quickly and cheaply balance large and uncertain time-varying differences between demand and electricity generation; electrified substitutes for most fuel-using devices; alternative materials and manufacturing processes for structural materials; and carbon-neutral fuels for the parts of the economy that are not easily electrified. Recycling and removal of carbon from the atmosphere (carbon management) is also likely to be an important activity of any net-zero emissions energy system. The specific technologies that will be favored in future marketplaces are largely uncertain, but only a finite number of technology choices exist today for each functional role. To take appropriate actions in the near term, it is imperative to clearly identify desired end points. To achieve a robust, reliable, and affordable net-zero emissions energy system later this century, efforts to research, develop, demonstrate, and deploy those candidate technologies must start now. OUTLOOK Combinations of known technologies could eliminate emissions related to all essential energy services and processes, but substantial increases in costs are an immediate barrier to avoiding emissions in each category. In some cases, innovation and deployment can be expected to reduce costs and create new options. More rapid changes may depend on coordinating operations across energy and industry sectors, which could help boost utilization rates of capital-intensive assets, but this will require overcoming institutional and organizational challenges in order to create new markets and ensure cooperation among regulators and disparate, risk-averse businesses. Two parallel and broad streams of research and development could prove useful: research in technologies and approaches that can decarbonize provision of the most difficult-to-decarbonize energy services, and research in systems integration that would allow reliable and cost-effective provision of these services. A shower of molten metal in a steel foundry. Industrial processes such as steelmaking will be particularly challenging to decarbonize. Meeting future demand for such difficult-to-decarbonize energy services and industrial products without adding CO2 to the atmosphere may depend on technological cost reductions via research and innovation, as well as coordinated deployment and integration of operations across currently discrete energy industries. Some energy services and industrial processes—such as long-distance freight transport, air travel, highly reliable electricity, and steel and cement manufacturing—are particularly difficult to provide without adding carbon dioxide (CO2) to the atmosphere. Rapidly growing demand for these services, combined with long lead times for technology development and long lifetimes of energy infrastructure, make decarbonization of these services both essential and urgent. We examine barriers and opportunities associated with these difficult-to-decarbonize services and processes, including possible technological solutions and research and development priorities. A range of existing technologies could meet future demands for these services and processes without net addition of CO2 to the atmosphere, but their use may depend on a combination of cost reductions via research and innovation, as well as coordinated deployment and integration of operations across currently discrete energy industries.

J. Rissman, C. Bataille, E. Masanet et al.

Abstract Fully decarbonizing global industry is essential to achieving climate stabilization, and reaching net zero greenhouse gas emissions by 2050–2070 is necessary to limit global warming to 2 °C. This paper assembles and evaluates technical and policy interventions, both on the supply side and on the demand side. It identifies measures that, employed together, can achieve net zero industrial emissions in the required timeframe. Key supply-side technologies include energy efficiency (especially at the system level), carbon capture, electrification, and zero-carbon hydrogen as a heat source and chemical feedstock. There are also promising technologies specific to each of the three top-emitting industries: cement, iron & steel, and chemicals & plastics. These include cement admixtures and alternative chemistries, several technological routes for zero-carbon steelmaking, and novel chemical catalysts and separation technologies. Crucial demand-side approaches include material-efficient design, reductions in material waste, substituting low-carbon for high-carbon materials, and circular economy interventions (such as improving product longevity, reusability, ease of refurbishment, and recyclability). Strategic, well-designed policy can accelerate innovation and provide incentives for technology deployment. High-value policies include carbon pricing with border adjustments or other price signals; robust government support for research, development, and deployment; and energy efficiency or emissions standards. These core policies should be supported by labeling and government procurement of low-carbon products, data collection and disclosure requirements, and recycling incentives. In implementing these policies, care must be taken to ensure a just transition for displaced workers and affected communities. Similarly, decarbonization must complement the human and economic development of low- and middle-income countries.

C. Kumar. J, M. Majid

The primary objective for deploying renewable energy in India is to advance economic development, improve energy security, improve access to energy, and mitigate climate change. Sustainable development is possible by use of sustainable energy and by ensuring access to affordable, reliable, sustainable, and modern energy for citizens. Strong government support and the increasingly opportune economic situation have pushed India to be one of the top leaders in the world’s most attractive renewable energy markets. The government has designed policies, programs, and a liberal environment to attract foreign investments to ramp up the country in the renewable energy market at a rapid rate. It is anticipated that the renewable energy sector can create a large number of domestic jobs over the following years. This paper aims to present significant achievements, prospects, projections, generation of electricity, as well as challenges and investment and employment opportunities due to the development of renewable energy in India. In this review, we have identified the various obstacles faced by the renewable sector. The recommendations based on the review outcomes will provide useful information for policymakers, innovators, project developers, investors, industries, associated stakeholders and departments, researchers, and scientists.

Xi Yang, C. Nielsen, Shaojie Song et al.

Countries such as China are facing a bottleneck in their paths to carbon neutrality: abating emissions in heavy industries and heavy-duty transport. There are few in-depth studies of the prospective role for clean hydrogen in these ‘hard-to-abate’ (HTA) sectors. Here we carry out an integrated dynamic least-cost modelling analysis. Results show that, first, clean hydrogen can be both a major energy carrier and feedstock that can significantly reduce carbon emissions of heavy industry. It can also fuel up to 50% of China’s heavy-duty truck and bus fleets by 2060 and significant shares of shipping. Second, a realistic clean hydrogen scenario that reaches 65.7 Mt of production in 2060 could avoid US$1.72 trillion of new investment compared with a no-hydrogen scenario. This study provides evidence of the value of clean hydrogen in HTA sectors for China and countries facing similar challenges in reducing emissions to achieve net-zero goals. Clean hydrogen could play a pivotal role in decarbonization but the paths for different sectors remain to be understood. Yang et al. present detailed scenarios to 2060 to explore options for using clean hydrogen in China’s economy for the sectors of industry and transport that are hard to abate.

Mihira Kumar Nath, N. Bhanu Prasad, Asini Kumar Baliarsingh

Renewable energy sources (RESs) hold a significant share in modern electrical networks, particularly in Microgrids (MGs). The inertia of the MG is significantly reduced due to the substitution of traditional synchronous generators with RESs. Frequency control of MG integrated with RESs is a challenging task. This research proposes a robust solution to enhance the frequency stability of an islanded MG by applying virtual inertia control (VIC) and damping strategies. A multistage proportional integral derivative (PID) ([PDF]-[1+PI]) controller optimized through a modified golf optimization algorithm (mGOA) in coordination with an energy storage system (ESS) is implemented as VIC. The mGOA algorithm performance is compared using various standard benchmark test functions with the original golf optimization algorithm (GOA) and with 10 other well-known optimization algorithms, particle swarm optimization, gravitational search algorithm, and genetic algorithm. To verify the effectiveness of the proposed mGOA algorithm, it is compared with the original GOA, grey wolf optimization (GWO), and whale optimization algorithm (WOA). It is demonstrated that the objective function value decreases by 53.07%, 56.01%, and 60.53% when compared with the original GOA, WOA, and GWO, respectively. The performance of the proportional derivative with filter (PDF)-(1+PI) controller was compared with that of conventional proportional integral (PI) controllers and PID controllers based on mGOA for random load fluctuation, parametric uncertainty, reduced capacity of ESS, and various renewable generation scenarios. The simulation result indicates that the mGOA-tuned multistage controller offers improved performance of 85.65% and 82.62% in terms of minimum objective function value in comparison to the mGOA-tuned PI and PID controllers, respectively. The performance of the proposed controller is evaluated under cyber attacks like false data injection attacks and denial of service attacks, as well as time latency. Performance of the proposed controller is tested by Hardware-In-The-Loop simulation, in OPAL-RT platform.

Hussein A. Younus, Rashid Al Hajri, Nazir Ahmad et al.

Jing Cao, Hancheng Dai, Shantong Li et al.

Abstract We conduct a multi-model comparison of a carbon tax policy in China to examine how different models simulate the impacts in both near-term 2020, medium-term 2030, and distant future 2050. Though Top-down computable general equilibrium (CGE) models have been applied frequently on climate or other environmental/energy policies to assess emission reduction, energy use and economy-wide general equilibrium outcomes in China, the results often vary greatly across models, making it challenging to derive policies. We compare 8 China CGE models with different characteristics to examine how they estimate the effects of a plausible range of carbon tax scenarios – low, medium and high carbon taxes.. To make them comparable we impose the same population growth, the same GDP growth path and world energy price shocks. We find that the 2030 NDC target for China are easily met in all models, but the 2060 carbon neutrality goal cannot be achieved even with our highest carbon tax rates. Through this carbon tax comparison, we find all 8 CGE models differ substantially in terms of impacts on the macroeconomy, aggregate prices, energy use and carbon reductions, as well as industry level output and price effects. We discuss the reasons for the divergent simulation results including differences in model structure, substitution parameters, baseline renewable penetration and methods of revenue recycling.

Jingyu Li, Bing-Ang Mei, Huihua Feng et al.

Redox additives have been widely used in various electrolytes to achieve an increase in the energy density of hybrid capacitors. This study investigates the trade-off mechanism of energy density and cycle stability for electrochemical capacitors with redox additives. To do so, a 1-dimensional electrochemical model considering both electric double layer and redox actions is performed for carbon-based hybrid capacitors with electrolyte of 1 mol L−1 tetraethylammonium tetrafluoroborate/acetonitrile and redox additives hydroquinone. The results show that electrochemical capacitors with redox additives worked in either Faradaic or capacitive regimes, distinguished by the “capacitor-like” or “battery-like” potential-time curve. In addition, the energy density of the device increased with the increase in concentration of hydroquinone and the decrease in imposed current density. The temporal evolution of Coulombic efficiency and spatial average concentration of hydroquinone over cycles indicate a transition from developing state to steady state. The number of cycles required for both parameters to stabilize is identical. Finally, the Faradaic regime is favored for energy density improvement. On the other hand, highly weighted cycle stability could allow relatively higher imposed current density. The results of this study can be used to further guide the design and optimization of hybrid electrochemical systems with redox additives.

Sorin Anagnoste, Alexandru-Victor Andrei, Vlad Bolovăneanu et al.

Energy finance is an interdisciplinary, rapidly evolving field integrating finance, economics, and energy systems to address complex challenges in market dynamics, sustainability, and policy-making amidst global energy transitions to net zero. Recent advances in artificial intelligence have reshaped energy finance research and practice, but no prior study has systematically examined how these methods have been applied across the field or what value they have brought. This paper provides a comprehensive review of approximately 700 academic studies published over the past five years, analyzing the diffusion and contribution of AI techniques across the six established thematic areas proposed by Zhang et al. (2018). While machine learning models are increasingly adopted, especially in forecasting applications, and often outperform classical econometric approaches in terms of accuracy, their use remains uneven. In some cases, methodological choices are clearly adapted to the structure of the data and the objective of the study, while in others, the implementation of complex ML algorithms lacks contextual justification or interpretability. More importantly, the review highlights a major gap, namely recent approaches such as explainable AI and causal machine learning are almost entirely absent, despite their potential to enhance transparency, support causal inference, and inform energy-related financial decisions. By identifying where AI has already contributed, where it remains underused, and how it could be better integrated, the paper offers a structured and forward-looking perspective on the evolving relationship between artificial intelligence and energy finance.

Jose M. Mena-Valle

The strong coupling $α_s$ is extracted with high precision through fits to lattice-QCD data for the static energy. Our theoretical framework is based on R-improving the three-loop fixed-order prediction for the static energy: we remove the $u=1/2$ renormalon and resum the associated large infrared logarithms. Combined with radius-dependent renormalization scales (the so-called profile functions), this procedure extends the range of validity of perturbation theory to distances as large as $\sim 0.5\,$fm. In addition, we resum large ultrasoft logarithms to N$^3$LL accuracy using renormalization-group evolution. Since the standard four-loop R-evolution treats N$^4$LL and higher-order contributions asymmetrically, we also incorporate this potential source of bias in our analysis. Our estimate of the perturbative uncertainty is obtained through a random scan over the parameters controlling the profile functions and the implementation of R-evolution. We analyze how the extracted value of $α_s$ depends on the shortest and longest distances included in the fit, on the details of the R-evolution procedure, on the fitting strategy itself, and on the accuracy of ultrasoft resummation. From our final analysis, and after evolution to the $Z$ pole, we obtain $α^{(n_f=5)}_s(m_Z)=0.1170\pm 0.0009$, a result fully compatible with the world average and with a comparable uncertainty.

Harald Grosse, Albert Much

We present a quantum energy inequality (QEI) for quantum field theories formulated in non-commutative spacetimes, extending fundamental energy constraints to this generalized geometric framework. By leveraging operator-theoretic methods inspired by the positivity map of Waldmann et al. \cite{waldmannpos}, we construct linear combinations of deformed operators that generalize the commutative spacetime techniques of Fewster et al., \cite{Few98}. These non-commutative analogs enable us the derivation of a lower bound on the deformed averaged energy density, ensuring the stability of the underlying quantum field theory. Our result establishes rigorous constraints on the expectation values of the deformed (non-commutative) energy density, reinforcing the physical consistency of non-commutative models while preserving core principles of quantum field theory.

Babak Mousavi, N. Lopez, J. B. M. Biona et al.

Yue Yin, Jing Wang, Lei Li

Currently, the global energy structure is undergoing a transition from fossil fuels to renewable energy sources, with the hydrogen economy playing a pivotal role. Hydrogen is not only an important energy carrier needed to achieve the global goal of energy conservation and emission reduction, it represents a key object of the future international energy trade. As hydrogen trade expands, nations are increasingly allocating resources to enhance the international competitiveness of their respective hydrogen industries. This paper introduces an index that can be used to evaluate international hydrogen competitiveness and elucidate the most competitive countries in the hydrogen trade. To calculate the competitiveness scores of seven major prospective hydrogen market participants, we employed the entropy weight method. This method considers five essential factors: potential resources, economic and financial base, infrastructure, government support and institutional environment, and technological feasibility. The results indicate that the USA and Australia exhibit the highest composite indices. These findings can serve as a guide for countries in formulating suitable policies and strategies to bolster the development and international competitiveness of their respective hydrogen industries.

Xiaocun Sun, Lingfeng Shi, Meiyan Zhang et al.

Abstract Thermal-integrated pumped thermal electricity storage (TI-PTES) could realize efficient energy storage for fluctuating and intermittent renewable energy. However, the boundary conditions of TI-PTES may frequently change with the variation of times and seasons, which causes a tremendous deterioration to the operating performance. To realize efficient and flexible energy storage in operating conditions, a novel composition-adjustable TI-PTES is proposed, and the operating performance is investigated and compared with composition-fixed TI-PTES. Simulation results show that, compared to composition-fixed TI-PTES, the energy storage efficiency of TI-PTES could be enhanced by the absolute value of 4.4–18.3% by introducing composition adjustment method under various boundary conditions. Besides, tuning sub-system composition could simultaneously adjust the capacities of power input, heat storage and power output, realizing a more flexible operating range for TI-PTES. A case study for an isolated energy community shows that composition-adjustable TI-PTES could realize 100% conversion of off-peak electric energy and reduce daily investment by 35.6% compared with composition-fixed TI-PTES.

Yufei Wang

The global new energy vehicle industry is currently in a phase of rapid development, with the growth of China's new energy electric vehicle sector being dynamically regulated by various factors within the overall market. Consequently, this study considers the competitive relationship with traditional fuel vehicles and the policy and economic factors present in international trade. Utilizing system dynamics models and dynamic simulations based on graph theory, the research analyzes the future development trends of the overall automobile market and China's new energy electric vehicles. The results indicate that electric vehicles globally will have a disruptive impact on the traditional fuel vehicle market. In situations where China's new energy electric vehicles significantly challenge the traditional fuel vehicle market, the market share of electric vehicles is expected to grow at a high rate over the next 30 years, rapidly increasing from 0.4 to 0.87. Different governmental guidance measures can create up to a 17% difference in market share. In foreign markets, under the global context of 'carbon peaking' and other low-carbon initiatives, or in scenarios where Chinese electric vehicles have a competitive advantage, the impact on the development of China's new energy vehicle industry is relatively minor.

Daniel May, Matthew Taylor, Petr Musilek

As distributed energy resources (DERs) grow, the electricity grid faces increased net load variability at the grid edge, impacting operability and reliability. Transactive energy, facilitated through local energy markets, offers a decentralized, indirect demand response solution, with model-free control techniques, such as deep reinforcement learning (DRL), enabling automated, decentralized participation. However, existing studies largely overlook community-level net load variability, focusing instead on socioeconomic metrics. This study addresses this gap by using DRL agents to automate end-user participation in a local energy market (ALEX), where agents act independently to minimize individual energy bills. Results reveal a strong link between bill reduction and decreased net load variability, assessed across metrics such as ramping rate, load factor, and peak demand over various time horizons. Using a no-control baseline, DRL agents are benchmarked against a near-optimal dynamic programming approach. The dynamic programming benchmark achieves reductions of 22.05 percent, 83.92 percent, and 24.09 percent in daily import, export, and peak demand, respectively, while the DRL agents show comparable or superior results with reductions of 21.93 percent, 84.46 percent, and 27.02 percent. This study demonstrates the effectiveness of DRL in decentralized grid management, highlighting its scalability and near-optimal performance in reducing net load variability within community-driven energy markets.

Javaid Tantry, Zahir Shah, Ranjeev Misra et al.

We conducted a multi-wavelength analysis of the blazar Mrk\,501, utilizing observations from \emph{Astro}Sat (SXT, LAXPC), \emph{Swift-UVOT}, and \emph{Fermi-LAT} during the period August 15, 2016 to March 27, 2022. The resulting multi-wavelength light curve revealed relatively low activity of the source across the electromagnetic spectrum. Notably, logparabola and broken power-law models provided a better fit to the joint X-ray spectra from \emph{Astro}Sat-SXT/LAXPC instruments compared to the power-law model. During the low activity state, the source showed the characteristic harder when brighter trend at the X-ray energies. To gain insights into underlying physical processes responsible for the broadband emission, we performed a detailed broadband spectral analysis using the convolved one-zone leptonic model with different forms of particle distributions such as logparabola (LP), broken power-law (BPL), power-law model with maximum energy ($ξ_{max}$), and energy-dependent acceleration (EDA) models. Our analysis revealed similar reduced-$χ^2$ values for the four particle distributions. The LP and EDA models exhibited the lowest jet powers. The correlation analyses conducted for the LP and BPL models revealed that there is a positive correlation between jet power and bulk Lorentz factor. Specifically, in the LP model, jet power proved independent of $γ_{min}$, whereas in the broken power-law model, jet power decreased with an increase in $γ_{min}$. The jet power in the LP/EDA particle distribution is nearly 10 percent of the Eddington luminosity of a $10^7$ M$_\odot$ black hole. This result suggests that the jet could potentially be fueled by accretion processes.

Julia M. Wittmayer, F. Avelino, B. Pel et al.

Renewable energy (RE) prosumerism comes with promises and expectations of contributing to sustainable and just energy systems. In its current process of becoming mainstream, numerous challenges and doubts have arisen whether it will live up to these. Building on insights from sustainability transitions research and institutional theory, this article unpacks the mainstreaming by considering the range of institutional arrangements and logics through which these contributions might be secured. Taking a Multi-actor Perspective, it analyses the differences, combinations, and tensions between institutional logics, associated actor roles and power relations. Firstly, it unpacks how mainstreaming occurs through mechanisms of bureaucratisation and standardisation (state logic), marketisation and commodification (market logic), as well as socialisation and communalisation (community logic). Secondly, it highlights the concomitant hybridisation of institutional logics and actor roles. Such hybrid institutional arrangements try to reconcile not only the more known trade-offs and tensions between for-profit/non-profit logics (regarding the distribution of benefits for energy activities and resources), but also between formal/informal logics (gaining recognition) and public/private logics (delineating access). This institutional concreteness moves the scholarly discussion and policy debate beyond idealistic discussions of ethical principles and abstract discussions about power: Simplistic framings of ‘prosumerism vs incumbents’ are dropped in favour of a critical discussion of hybrid institutional arrangements and their capacity to safeguard particular transformative ideals and normative commitments.

Yueyang Wang, Qi Li, Qi Li et al.

Aqueous Zn-organic batteries (AZOBs) stand out in the family of aqueous Zn devices due to high theoretical capacity, tunable structures, sustainable resources, and low cost of organic hosts. However, the development of advanced AZOBs faces numerous issues and challenges, including, poor conductivity, low actual capacity, serve molecular dissolution, and unsatisfying energy density. Herein, we summarize an overview of various organic materials as the inserted ion hosts. In addition to categorizing organic compounds based on their functional groups, this report also covers the latest developments in organic cathodes and their energy storage mechanisms. Furthermore, strategies for advanced Zn-organic devices are suggested with regard to structural design and important battery metrics. Moreover, challenges and perspectives are finally discussed from the point of view of full batteries. We hope this review can provide a valuable evaluation of commercial Zn-organic batteries and spur new insights toward a greener energy world.

Benjamin Schumm, Stefan Kaskel