Understanding how renewable energy generation affects electricity prices is essential for designing efficient and sustainable electricity markets.However,most existing studies rely on regression-based approaches that ...Understanding how renewable energy generation affects electricity prices is essential for designing efficient and sustainable electricity markets.However,most existing studies rely on regression-based approaches that capture correlations but fail to identify causal relationships,particularly in the presence of non-linearities and confounding factors.This limits their value for informing policy and market design in the context of the energy transition.To address this gap,we propose a novel causal inference framework based on local partially linear double machine learning(DML).Our method isolates the true impact of predicted wind and solar power generation on electricity prices by controlling for high-dimensional confounders and allowing for non-linear,context-dependent effects.This represents a substantial methodological advancement over standard econometric techniques.Applying this framework to the UK electricity market over the period 2018-2024,we produce the first robust causal estimates of how renewables affect dayahead wholesale electricity prices.We find that wind power exerts a U-shaped causal effect:at low penetration levels,a 1 GWh increase reduces prices by up to£7/MWh,the effect weakens at mid-levels,and intensifies again at higher penetration.Solar power consistently reduces prices at low penetration levels,up to£9/MWh per additional GWh,but its marginal effect diminishes quickly.Importantly,the magnitude of these effects has increased over time,reflecting the growing influence of renewables on price formation as their share in the energy mix rises.These findings offer a sound empirical basis for improving the design of support schemes,refining capacity planning,and enhancing electricity market efficiency.By providing a robust causal understanding of renewable impacts,our study contributes both methodological innovation and actionable insights to guide future energy policy.展开更多
The continuously increasing renewable energy sources(RES)and demand response(DR)are becoming crucial sources of system flexibility.Consequently,decision-dependent uncertainties(DDUs),inter-changeably referred to as en...The continuously increasing renewable energy sources(RES)and demand response(DR)are becoming crucial sources of system flexibility.Consequently,decision-dependent uncertainties(DDUs),inter-changeably referred to as endogenous uncertainties,impose new characteristics on power system dis-patch.The DDUs faced by system operators originate from uncertain dispatchable resources such as RES units or DR,while reserve providers encounter DDUs from the uncertain reserve deployment.Thus,a systematic framework was established in this study to address robust dispatch problems with DDUs.The main contributions are drawn as follows.①The robust characterization of DDUs was unfolded with a dependency decomposition structure.②A generic DDU coping mechanism was manifested as the bilateral matching between uncertainty and flexibility.③The influence of DDU incorporation on the convexity/non-convexity of robust dispatch problems was analyzed.④Generic solution algorithms adaptive for DDUs were proposed.Under this framework,the inherent distinctions and correlations between DDUs and decision-independent uncertainties(DIUs)were revealed,laying a fundamental theoretical foundation for the economic and reliable operation of RES-dominated power systems.Illustrative applications in the source and demand sides are provided to show the significance of considering DDUs and demonstrate the proposed theoretical results.展开更多
The circular economy(CE)presents a promising approach to integrating industry with sustainability and circularity,which helps minimize ecological harm and preserve natural resources for future generations.This study f...The circular economy(CE)presents a promising approach to integrating industry with sustainability and circularity,which helps minimize ecological harm and preserve natural resources for future generations.This study focused on the roles of nuclear energy,renewables,and climate policies in advancing a CE.It examined the intentions of OECD countries regarding CE practices and the various factors influencing these intentions from 2000 to 2019.This study utilized second-generation panel data tools,such as slope homogeneity and stationarity tests,to assess cross-sectional dependence and heterogeneity in the panel dataset.The study employed the moment quantile regression(MM-QR)method to obtain regression estimates and analyze the conditional distribution across all quantiles.The findings indicated that the role of nuclear energy in promoting CE was negative across all quantiles.In contrast,renewable energy positively supports achieving CE in OECD countries.Climate policies assisted OECD countries in progressing toward CE in both the nuclear energy and renewable energy models.We conducted a robust check using a non-parametric panel Granger causality test,which confirmed the expected results for all other factors.The collaborative efforts for waste minimization ensure that nuclear energy systems are resilient,economically feasible,and environmentally sustainable.展开更多
The implementation of higher shares of renewables in a global energy mix has to be accompanied by simultaneous deployment of enabling smart grid technologies （SGTs）. This combination will inevitably lead to a revolu...The implementation of higher shares of renewables in a global energy mix has to be accompanied by simultaneous deployment of enabling smart grid technologies （SGTs）. This combination will inevitably lead to a revolutionary change in a conventional energy system, particularly, the shifting role of consumers to prosnmers. But resistance may arise from such a dramatic shift, since it is associated with high uncertainty in conjunction with increasing responsibilities of all stakeholders, the urgent need of effective control, and the development of a process. To ensure the positive influence, coherent actions of all players, and appropriate treatment of the spots of resistance, the analysis of the interplay between key stakeholders has been done. The paper introduces the framework for stakeholders＇ analysis, applies it on the European Union （EU） example, and provides recommendations to reduce the resistance of SGTs deployment.展开更多
In this study,a bald eagle optimizer(BEO)is used to get optimal parameters of the fractional-order proportional-integral-derivative(FOPID)controller for load frequency control(LFC).SinceBEOtakes only a very short time...In this study,a bald eagle optimizer(BEO)is used to get optimal parameters of the fractional-order proportional-integral-derivative(FOPID)controller for load frequency control(LFC).SinceBEOtakes only a very short time in finding the optimal solution,it is selected for designing the FOPID controller that improves the system stability and maintains the frequency within a satisfactory range at different loads.Simulations and demonstrations are carried out using MATLAB-R2020b.The performance of the BEOFOPID controller is evaluated using a two-zone interlinked power system at different loads and under uncertainty of wind and solar energies.The robustness of the BEO-FOPID controller is examined by testing its performance under varying system time constants.The results obtained by the BEOFOPID controller are compared with those obtained by BEO-PID and PID controllers based on recent metaheuristics optimization algorithms,namely the sine-cosine approach,Jaya approach,grey wolf optimizer,genetic algorithm,bacteria foraging optimizer,and equilibrium optimization algorithm.The results confirm that the BEO-FOPID controller obtains the finest result,with the lowest frequency deviation.The results also confirm that the BEOFOPID controller is stable and robust at different loads,under varying system time constants,and under uncertainty of wind and solar energies.展开更多
With the continuous growing of population and the economical needs in the Balkan region,as in the whole world,the needfor new energy resources is getting more reasonable than ever.Considering the nowadays exponential ...With the continuous growing of population and the economical needs in the Balkan region,as in the whole world,the needfor new energy resources is getting more reasonable than ever.Considering the nowadays exponential growth in development of therenewable energy sources,in this paper,a comparison of the hydropower energy capacities with the wind and solar energy sources,in the territory of Kosova is generally presented.Today,the territory of Kosova,has 1,513 MW installed capacity of electricity,which is generated from two thermo-power plants KOSOVA A and KOSOVA B.This energy generation capacity is proved to beinsufficient for meeting the entire electricity needs of the 2 million population and the overall economical development.In this paper,a specific attention is given to the electricity generation by the renewable energy sources as the wind and hydropower.A specificemphasis is given to the combination of hydropower with wind power,in Kosova,as a optimal solution for the generation of therenewable energy sources.In this paper,a concrete idea for combining the ZHUR hydro-powerplant system with the numerous windturbines is given,which could be placed in the near zone of this hydropower-plant.In combination,these electricity regeneratorswould promise a more reliable energy source,and contribute to the fulfilment of the overall electricity requirements of Kosova.展开更多
Multi-GW renewables need multi-GW storage, or fossil fuelled power stations will be needed to balance for intermittency. For the same reason, such balancing must be able to last for an entire evening peak if renewable...Multi-GW renewables need multi-GW storage, or fossil fuelled power stations will be needed to balance for intermittency. For the same reason, such balancing must be able to last for an entire evening peak if renewables are not generating at the same time. Batteries and DSR （demand side response） make very useful contributions and there is a large market for both, but without large scale and long duration storage, they cannot do the job. Interconnectors also contribute to the solution, and storage will make them more profitable, but （taking a UK perspective） Ofgem identified that all our neighbours have similar generation capacity crunches and similar demand patters, so if we need the electricity when they do, we’ll have to pay through the nose for it. Last winter’s ￡ 1,500/MWh prices proved that―even with only 4 GW interconnection. Following exit from the single market, our neighbours will be able to say “our consumers are more important than yours at any price”. We need UK-based storage at the right scale, to store UK-generated electricity for UK use and for export―otherwise we lose security of supply. CAES （compressed air energy storage） and pumped hydro are the only technologies currently able to deliver this scale and duration of storage. Pumped hydro is cost-effective in the long term but there are few sites, and it is （location dependent） over 3x the cost of CAES. Storelectric has 2 versions of CAES： one is a comparable price to existing CAES, but much more efficient （~70% v 50%） and zero emissions （existing CAES emits 50%-60% of the gas of an equivalent sized power station）. The other is retro-fittable to suitable gas power stations, is more efficient （-60% v 50%）, almost halves their emissions, adds storage-related revenue streams and is much cheaper. Both are new configurations of existing and well proven technologies, supported by engineering majors.展开更多
This paper investigates the safe energy management of emerging shared renewables and refined oil transmission systems(SRROTSs)during the energy transition.Specifically,a continuous-time energy management model that co...This paper investigates the safe energy management of emerging shared renewables and refined oil transmission systems(SRROTSs)during the energy transition.Specifically,a continuous-time energy management model that considers the SRROTSs'multi-product sequential transmission characteristics is proposed to guide safe and efficient system operation.This model is also convenient for on-site dispatchers to operate.Correspondingly,a solver-free physics-informed particle swarm optimisation(PI-PSO)algorithm is tailored,utilising physical rules to regulate particle mutation and adapted to solve the proposed model,thereby enhancing the optimality and stability of the solution.Case studies on real-world SRROTSs are utilised to validate the proposed model and PI-PSO algorithm,which are expected to be generalised to other pipeline transmission systems.Especially,the PI-PSO algorithm achieves a 25.6%energy reduction compared to the original PSO algorithm,although a trade-off between improving the objective value and the number of iterations needed for convergence is observed.展开更多
With the rapid expansion of urban road networks and the increasing ownership of vehicles in many countries and regions, the greenhouse gas and pollutant emissions from road travels have become a global concern. The in...With the rapid expansion of urban road networks and the increasing ownership of vehicles in many countries and regions, the greenhouse gas and pollutant emissions from road travels have become a global concern. The introduction of electric vehicles(EVs) with dynamic charging into road systems, which is defined as electric road systems(ERSs), has been widely recognized as a viable solution to address this problem. This paper presents a comprehensive study on the reliability of power supply systems integrated with renewables for ERS(ERSPSRs), which interface with both road traffic and power networks. First, a brief introduction to the charging modes of EVs demonstrates the coupling of the two networks. A simplified traffic model is then built, based on which the reliability indices of the system considering the influence of the dynamic charging and static charging modes of EVs are proposed. Further, a simplified trip chain based Monte Carlo reliability assessment method of ERS-PSRs is proposed. Case studies based on the IEEE Roy Billinton Test System(RBTS) show that the dynamic charging mode of EVs can not only effectively balance the supply and demand of the power grid at different time(shaving peaks and filling valleys), but also significantly improve the reliability of ERS-PSRs. The case studies also examine the effects of the ratio of EVs with dynamic charging, wind generation penetration rate, additional wind power, and battery energy storage systems(BESSs) on the reliability of ERS-PSRs.展开更多
Portugal is seen worldwide as a case of success in the large-scale integration of renewables in its power system,especially for wind power.Consistent policies and sound management decisions are fundamental,but a susta...Portugal is seen worldwide as a case of success in the large-scale integration of renewables in its power system,especially for wind power.Consistent policies and sound management decisions are fundamental,but a sustainable process is not possible without the development of endogenous knowledge.This paper summarizes a set of models,both applied by the industry and representing actual technologic advancement,denoting the context of research and innovation in the country that helps to explain such success.Novelties arise in reliability assessment for systems with renewables,active and reactive power control,integration of wind farms,storage,electric vehicle integration,wind and solar power forecasting and distribution operation and state estimation taking advantage of smart grid structures.In all cases,one relevant trait is evident:the pervasive use of computational intelligence tools.展开更多
This study proposes an optimized model of a micro-energy network(MEN)that includes electricity and natural gas with integrated solar,wind,and energy storage systems(ESSs).The proposed model is based on energy hubs(EHs...This study proposes an optimized model of a micro-energy network(MEN)that includes electricity and natural gas with integrated solar,wind,and energy storage systems(ESSs).The proposed model is based on energy hubs(EHs)and it aims to minimize operation costs and greenhouse emissions.The research is motivated by the increasing use of renewable energies and ESSs for secure energy supply while reducing operation costs and environment effects.A general algebraic modeling system(GAMS)is used to solve the optimal operation problem in the MEN.The results demonstrate that an optimal MEN formed by multiple EHs can provide appropriate and flexible responses to fluctuations in electricity prices and adjustments between time periods and seasons.It also yields significant reductions in operation costs and emissions.The proposed model can contribute to future research by providing a more efficient network model(as compared with the traditional electricity supply system)to scale down the environmental and economic impacts of electricity storage and supply systems on MEN operation.展开更多
The increasing penetration of renewables in power systems urgently entails the utilization of energy storage technologies.As the development of energy storage technologies depends highly on the profitability in electr...The increasing penetration of renewables in power systems urgently entails the utilization of energy storage technologies.As the development of energy storage technologies depends highly on the profitability in electricity markets,to evaluate the economic potentials for various types of energy storage technologies under the compre-hensive market environment is of great significance.To this end,this study aims at conducting a quantitative analysis on the economic potentials for typical energy storage technologies by establishing a joint clearing model for electric energy and ancillary service(AS)markets considering the operating features of energy storage systems(ESSs).Furthermore,a test system is adopted for numerical analysis that accurately represents for the real-world operation characteristics of power systems in China,with which the market prices,and operation schedules and profitability of ESSs are comparatively studied.The proposed methodology and results could provide benefi-cial references for the modifications on electricity markets and the development of ESSs towards the increasing penetration of renewables in power systems.展开更多
One purpose of stimulating financing and investment through private capital is to absorb a higher proportion of renewables and promote renewable industry development.This paper first reviews the current overall situat...One purpose of stimulating financing and investment through private capital is to absorb a higher proportion of renewables and promote renewable industry development.This paper first reviews the current overall situation of renewables financing and investment,and further analyzes the policy environment with respect to the development plan,regulation and special funds.Based on the analysis of the status quo,the paper then discusses the internalities and the externalities that have driven the changes of private capital investment in renewable energy projects,illustrated by a strength,weakness,opportunity and threat(SWOT)analysis.An ideal financing model,public-private partnership and distributed energy resource pattern are analyzed to identify key arrangements and design proper development schemes for both private investors and the government.If China can overcome the defects and obstacles in a reasonable and orderly fashion,the financing and investment problem of China’s renewables industry will be solved in many ways.Private capital in China’s renewable energy market will bring great incentive if the entire industry can select some promising sub-industries in the renewables sector and choose some appropriate operation modes.展开更多
In recent years,rumors have been shown to have a significant impact on individual and societal activities.As renewables play an increasingly significant role in electricity markets,certain rumors may deviate the biddi...In recent years,rumors have been shown to have a significant impact on individual and societal activities.As renewables play an increasingly significant role in electricity markets,certain rumors may deviate the bidding behavior of market entities and eventually affect the performance of market operations.In this study,we attempt to reveal the general threats caused by rumors in the context of day-ahead electricity markets considering the integration of volatile renewables.First,we model the propagation of rumors in the societal system considering the weight of propagation resistance,which principally reflects the communication accessibility of market entities.Second,we develop an integrated two-layer network model to uncover the inherent coupling mechanism between market operations and rumor propagation.In particular,the role of electricity market operations on rumor propagation is characterized by changes in the truthfulness of rumors associated with electricity prices.The rumors,in turn,affect the bidding quantities of market entities in electricity market operations.Finally,numerical experiments are conducted on modified IEEE 6-bus and 118-bus systems.The results demonstrate the potential threats of rumors to electricity market operations with different penetration levels of renewables.展开更多
0 INTRODUCTION Throughout human history,three major energy transitions have occurred:from burning wood in primitive times to using coal in 18th Century,then to oil and gas in 20th Century,and to the renewable energy r...0 INTRODUCTION Throughout human history,three major energy transitions have occurred:from burning wood in primitive times to using coal in 18th Century,then to oil and gas in 20th Century,and to the renewable energy revolution in the 21st Century(Zou et al.,2023).The three transitions have three characteristics in common:shifted from nonrenewable to renewable energy,from“resource-centric”to a“technology-centric”,and from“high-carbon fossil”to“net-zero”.展开更多
The rapid growth in available network bandwidth has directly contributed to an exponential increase in mobile data traffic,creating significant challenges for network energy consumption.Also,with the extraordinary gro...The rapid growth in available network bandwidth has directly contributed to an exponential increase in mobile data traffic,creating significant challenges for network energy consumption.Also,with the extraordinary growth of mobile communications,the data traffic has dramatically expanded,which has led to massive grid power consumption and incurred high operating expenditure(OPEX).However,the majority of current network designs struggle to efficientlymanage a massive amount of data using little power,which degrades energy efficiency performance.Thereby,it is necessary to have an efficient mechanism to reduce power consumption when processing large amounts of data in network data centers.Utilizing renewable energy sources to power the Cloud Radio Access Network(C-RAN)greatly reduces the need to purchase energy from the utility grid.In this paper,we propose a bandwidth-aware hybrid energypowered C-RAN that focuses on throughput and energy efficiency(EE)by lowering grid usage,aiming to enhance the EE.This paper examines the energy efficiency,spectral efficiency(SE),and average on-grid energy consumption,dealing with the major challenges of the temporal and spatial nature of traffic and renewable energy generation across various network setups.To assess the effectiveness of the suggested network by changing the transmission bandwidth,a comprehensive simulation has been conducted.The numerical findings support the efficacy of the suggested approach.展开更多
Photoreforming is an emerging photocatalytic process that converts organic waste into hydrogen H2 using solar energy,offering a dual solution for waste valorization and sustainable fuel production.This review comprehe...Photoreforming is an emerging photocatalytic process that converts organic waste into hydrogen H2 using solar energy,offering a dual solution for waste valorization and sustainable fuel production.This review comprehensively examines the fundamental mechanisms of photoreforming,emphasizing the critical role of photocatalyst design in optimizing hydrogen evolution.Key criteria for effective photocatalysts including suitable band edge positions,broad spectrum solar absorption,and photostability are systematically analyzed alongside advances in heterojunction engineering and defect modulation.The review further explores diverse waste-derived feedstocks,such as biomass:alcohols,saccharides,lignin and plastics:PET,PLA,polyolefins,highlighting substrate,specific challenges and pretreatment strategies.Despite progress,challenges like catalyst deactivation,limited visible-light utilization,and scalability persist.Future directions advocate for robust photocatalyst engineering,mechanistic insights into charge dynamics,and scalable reactor designs to realize photoreforming’s potential as a sustainable hydrogen production technology.展开更多
This insightful review explores the electrochemical principles and energy potential of electrocatalytic water splitting(EWS).It highlights recent advancements,identifies key challenges,and underscores the pivotal role...This insightful review explores the electrochemical principles and energy potential of electrocatalytic water splitting(EWS).It highlights recent advancements,identifies key challenges,and underscores the pivotal role of EWS in enabling the transition to sustainable energy systems.This work contextualizes the significance of green hydrogen in global decarbonization pathways and examines the historical progression of electrocatalysis.The fundamental thermodynamics and mechanistic pathways governing both the hydrogen and oxygen evolution reactions(HER and OER)are analyzed,highlighting energy barriers and rate-determining steps.Various electrode architectures and electrochemical cell configurations are evaluated,including a comparative assessment of key electrolyzer technologies and their performance characteristics.Furthermore,we critically examine recent advances and persistent limitations across the landscape of electrocatalysts,spanning noble metal-based materials,earth-abundant transition metal compounds,and emerging materials.Design principles and mechanistic insights drawn from electronic structu re modulation,defect engineering,doping strategies,and na noscale morphology control are elucidated to establish robust structure-property-performance relationships.Major challenges including sluggish oxygen evolution kinetics,catalyst degradation mechanisms,and the integration of devices with intermittent renewable energy sources are thoroughly examined.This work also debates advanced strategies such as hybrid photoelectrochemical systems,flexible device architectures,and the direct utilization of non-traditional water sources(e.g.,seawater,wastewater)as promising pathways for future development.Finally,it is specifically distinguished by its critical focus on bridging the gap between fundamental electrocatalysts development and practical system-level integration,addressing the challenges of scalability and deployment under industrially relevant conditions.This comprehensive review provides a strategic outlook and identifies key scientific priorities for optimizing EWS systems toward efficient,robust,and scalable hydrogen generation.展开更多
Driven by the global energy transition and carbon neutrality targets,alkaline water electrolysis has emerged as a key technology for coupling variable renewable generation with clean hydrogen production,offering consi...Driven by the global energy transition and carbon neutrality targets,alkaline water electrolysis has emerged as a key technology for coupling variable renewable generation with clean hydrogen production,offering considerable potential for absorbing surplus power and enhancing grid flexibility.However,conventional control architectures typically treat the power converter and electrolyzer as independent units,neglecting their dynamic interactions and thereby limiting overall system performance under practical operating conditions.This review critically examines existing control approaches,ranging from classical proportional-integral schemes to model predictive control,fuzzy-logic algorithms,and data-driven methods,evaluating their effectiveness in managing dynamic response,multivariable coupling,and operational constraints as well as their inherent limitations.Attention is then focused on the performance requirements of the hydrogen-production converter,including current ripple suppression,rapid transient response,adaptive thermal regulation,and stable power delivery.An integrated co‑control framework is proposed,aligning converter output with electrolyzer demand across steady-state operation,variable renewable input,and emergency shutdown scenarios to achieve higher efficiency,extended equipment lifetime,and enhanced operational safety.Finally,prospects for advancing unified control methodologies are outlined,with emphasis on constraint-aware predictive control,machine-learning-enhanced modeling,and real‑time co‑optimization for future alkaline electrolyzer systems.展开更多
The long-standing use of portable toilet cubicles by residents of Shanghai’s narrow,labyrinthine alleys came to an end in September 2025 after the city largely finished building public toilets to make up their lack o...The long-standing use of portable toilet cubicles by residents of Shanghai’s narrow,labyrinthine alleys came to an end in September 2025 after the city largely finished building public toilets to make up their lack of sanitation facilities.The project,targeting 14,082 households,started last year.展开更多
文摘Understanding how renewable energy generation affects electricity prices is essential for designing efficient and sustainable electricity markets.However,most existing studies rely on regression-based approaches that capture correlations but fail to identify causal relationships,particularly in the presence of non-linearities and confounding factors.This limits their value for informing policy and market design in the context of the energy transition.To address this gap,we propose a novel causal inference framework based on local partially linear double machine learning(DML).Our method isolates the true impact of predicted wind and solar power generation on electricity prices by controlling for high-dimensional confounders and allowing for non-linear,context-dependent effects.This represents a substantial methodological advancement over standard econometric techniques.Applying this framework to the UK electricity market over the period 2018-2024,we produce the first robust causal estimates of how renewables affect dayahead wholesale electricity prices.We find that wind power exerts a U-shaped causal effect:at low penetration levels,a 1 GWh increase reduces prices by up to£7/MWh,the effect weakens at mid-levels,and intensifies again at higher penetration.Solar power consistently reduces prices at low penetration levels,up to£9/MWh per additional GWh,but its marginal effect diminishes quickly.Importantly,the magnitude of these effects has increased over time,reflecting the growing influence of renewables on price formation as their share in the energy mix rises.These findings offer a sound empirical basis for improving the design of support schemes,refining capacity planning,and enhancing electricity market efficiency.By providing a robust causal understanding of renewable impacts,our study contributes both methodological innovation and actionable insights to guide future energy policy.
基金supported by the Joint Research Fund in Smart Grid(U1966601)under cooperative agreement between the National Natural Science Foundation of China(NSFC)and State Grid Corporation of China.
文摘The continuously increasing renewable energy sources(RES)and demand response(DR)are becoming crucial sources of system flexibility.Consequently,decision-dependent uncertainties(DDUs),inter-changeably referred to as endogenous uncertainties,impose new characteristics on power system dis-patch.The DDUs faced by system operators originate from uncertain dispatchable resources such as RES units or DR,while reserve providers encounter DDUs from the uncertain reserve deployment.Thus,a systematic framework was established in this study to address robust dispatch problems with DDUs.The main contributions are drawn as follows.①The robust characterization of DDUs was unfolded with a dependency decomposition structure.②A generic DDU coping mechanism was manifested as the bilateral matching between uncertainty and flexibility.③The influence of DDU incorporation on the convexity/non-convexity of robust dispatch problems was analyzed.④Generic solution algorithms adaptive for DDUs were proposed.Under this framework,the inherent distinctions and correlations between DDUs and decision-independent uncertainties(DIUs)were revealed,laying a fundamental theoretical foundation for the economic and reliable operation of RES-dominated power systems.Illustrative applications in the source and demand sides are provided to show the significance of considering DDUs and demonstrate the proposed theoretical results.
文摘The circular economy(CE)presents a promising approach to integrating industry with sustainability and circularity,which helps minimize ecological harm and preserve natural resources for future generations.This study focused on the roles of nuclear energy,renewables,and climate policies in advancing a CE.It examined the intentions of OECD countries regarding CE practices and the various factors influencing these intentions from 2000 to 2019.This study utilized second-generation panel data tools,such as slope homogeneity and stationarity tests,to assess cross-sectional dependence and heterogeneity in the panel dataset.The study employed the moment quantile regression(MM-QR)method to obtain regression estimates and analyze the conditional distribution across all quantiles.The findings indicated that the role of nuclear energy in promoting CE was negative across all quantiles.In contrast,renewable energy positively supports achieving CE in OECD countries.Climate policies assisted OECD countries in progressing toward CE in both the nuclear energy and renewable energy models.We conducted a robust check using a non-parametric panel Granger causality test,which confirmed the expected results for all other factors.The collaborative efforts for waste minimization ensure that nuclear energy systems are resilient,economically feasible,and environmentally sustainable.
文摘The implementation of higher shares of renewables in a global energy mix has to be accompanied by simultaneous deployment of enabling smart grid technologies （SGTs）. This combination will inevitably lead to a revolutionary change in a conventional energy system, particularly, the shifting role of consumers to prosnmers. But resistance may arise from such a dramatic shift, since it is associated with high uncertainty in conjunction with increasing responsibilities of all stakeholders, the urgent need of effective control, and the development of a process. To ensure the positive influence, coherent actions of all players, and appropriate treatment of the spots of resistance, the analysis of the interplay between key stakeholders has been done. The paper introduces the framework for stakeholders＇ analysis, applies it on the European Union （EU） example, and provides recommendations to reduce the resistance of SGTs deployment.
基金This research was funded by the Deputyship for Research&Innovation,Ministry of Education in Saudi Arabia through the project number“IF_2020_NBU_434”.
文摘In this study,a bald eagle optimizer(BEO)is used to get optimal parameters of the fractional-order proportional-integral-derivative(FOPID)controller for load frequency control(LFC).SinceBEOtakes only a very short time in finding the optimal solution,it is selected for designing the FOPID controller that improves the system stability and maintains the frequency within a satisfactory range at different loads.Simulations and demonstrations are carried out using MATLAB-R2020b.The performance of the BEOFOPID controller is evaluated using a two-zone interlinked power system at different loads and under uncertainty of wind and solar energies.The robustness of the BEO-FOPID controller is examined by testing its performance under varying system time constants.The results obtained by the BEOFOPID controller are compared with those obtained by BEO-PID and PID controllers based on recent metaheuristics optimization algorithms,namely the sine-cosine approach,Jaya approach,grey wolf optimizer,genetic algorithm,bacteria foraging optimizer,and equilibrium optimization algorithm.The results confirm that the BEO-FOPID controller obtains the finest result,with the lowest frequency deviation.The results also confirm that the BEOFOPID controller is stable and robust at different loads,under varying system time constants,and under uncertainty of wind and solar energies.
文摘With the continuous growing of population and the economical needs in the Balkan region,as in the whole world,the needfor new energy resources is getting more reasonable than ever.Considering the nowadays exponential growth in development of therenewable energy sources,in this paper,a comparison of the hydropower energy capacities with the wind and solar energy sources,in the territory of Kosova is generally presented.Today,the territory of Kosova,has 1,513 MW installed capacity of electricity,which is generated from two thermo-power plants KOSOVA A and KOSOVA B.This energy generation capacity is proved to beinsufficient for meeting the entire electricity needs of the 2 million population and the overall economical development.In this paper,a specific attention is given to the electricity generation by the renewable energy sources as the wind and hydropower.A specificemphasis is given to the combination of hydropower with wind power,in Kosova,as a optimal solution for the generation of therenewable energy sources.In this paper,a concrete idea for combining the ZHUR hydro-powerplant system with the numerous windturbines is given,which could be placed in the near zone of this hydropower-plant.In combination,these electricity regeneratorswould promise a more reliable energy source,and contribute to the fulfilment of the overall electricity requirements of Kosova.
文摘Multi-GW renewables need multi-GW storage, or fossil fuelled power stations will be needed to balance for intermittency. For the same reason, such balancing must be able to last for an entire evening peak if renewables are not generating at the same time. Batteries and DSR （demand side response） make very useful contributions and there is a large market for both, but without large scale and long duration storage, they cannot do the job. Interconnectors also contribute to the solution, and storage will make them more profitable, but （taking a UK perspective） Ofgem identified that all our neighbours have similar generation capacity crunches and similar demand patters, so if we need the electricity when they do, we’ll have to pay through the nose for it. Last winter’s ￡ 1,500/MWh prices proved that―even with only 4 GW interconnection. Following exit from the single market, our neighbours will be able to say “our consumers are more important than yours at any price”. We need UK-based storage at the right scale, to store UK-generated electricity for UK use and for export―otherwise we lose security of supply. CAES （compressed air energy storage） and pumped hydro are the only technologies currently able to deliver this scale and duration of storage. Pumped hydro is cost-effective in the long term but there are few sites, and it is （location dependent） over 3x the cost of CAES. Storelectric has 2 versions of CAES： one is a comparable price to existing CAES, but much more efficient （~70% v 50%） and zero emissions （existing CAES emits 50%-60% of the gas of an equivalent sized power station）. The other is retro-fittable to suitable gas power stations, is more efficient （-60% v 50%）, almost halves their emissions, adds storage-related revenue streams and is much cheaper. Both are new configurations of existing and well proven technologies, supported by engineering majors.
基金supported by the National Natural Science Foundation of China 52177089the Fundamental Research Funds for the Central Universities YCJJ20230463PipeChina South China Company GWHT20200001399.
文摘This paper investigates the safe energy management of emerging shared renewables and refined oil transmission systems(SRROTSs)during the energy transition.Specifically,a continuous-time energy management model that considers the SRROTSs'multi-product sequential transmission characteristics is proposed to guide safe and efficient system operation.This model is also convenient for on-site dispatchers to operate.Correspondingly,a solver-free physics-informed particle swarm optimisation(PI-PSO)algorithm is tailored,utilising physical rules to regulate particle mutation and adapted to solve the proposed model,thereby enhancing the optimality and stability of the solution.Case studies on real-world SRROTSs are utilised to validate the proposed model and PI-PSO algorithm,which are expected to be generalised to other pipeline transmission systems.Especially,the PI-PSO algorithm achieves a 25.6%energy reduction compared to the original PSO algorithm,although a trade-off between improving the objective value and the number of iterations needed for convergence is observed.
基金supported by the China Scholarship Council(No.202006130002).
文摘With the rapid expansion of urban road networks and the increasing ownership of vehicles in many countries and regions, the greenhouse gas and pollutant emissions from road travels have become a global concern. The introduction of electric vehicles(EVs) with dynamic charging into road systems, which is defined as electric road systems(ERSs), has been widely recognized as a viable solution to address this problem. This paper presents a comprehensive study on the reliability of power supply systems integrated with renewables for ERS(ERSPSRs), which interface with both road traffic and power networks. First, a brief introduction to the charging modes of EVs demonstrates the coupling of the two networks. A simplified traffic model is then built, based on which the reliability indices of the system considering the influence of the dynamic charging and static charging modes of EVs are proposed. Further, a simplified trip chain based Monte Carlo reliability assessment method of ERS-PSRs is proposed. Case studies based on the IEEE Roy Billinton Test System(RBTS) show that the dynamic charging mode of EVs can not only effectively balance the supply and demand of the power grid at different time(shaving peaks and filling valleys), but also significantly improve the reliability of ERS-PSRs. The case studies also examine the effects of the ratio of EVs with dynamic charging, wind generation penetration rate, additional wind power, and battery energy storage systems(BESSs) on the reliability of ERS-PSRs.
基金produced under conditions provided by funding by the ERDF–European Regional Development Fund through the Operational Programme for Competitiveness and Internationalization-COMPETE 2020 within project POCI-01-0145-FEDER-006961by national funds through the FCT-Portuguese Foundation for Science and Technology,as part of project UID/EEA/50014/2013.
文摘Portugal is seen worldwide as a case of success in the large-scale integration of renewables in its power system,especially for wind power.Consistent policies and sound management decisions are fundamental,but a sustainable process is not possible without the development of endogenous knowledge.This paper summarizes a set of models,both applied by the industry and representing actual technologic advancement,denoting the context of research and innovation in the country that helps to explain such success.Novelties arise in reliability assessment for systems with renewables,active and reactive power control,integration of wind farms,storage,electric vehicle integration,wind and solar power forecasting and distribution operation and state estimation taking advantage of smart grid structures.In all cases,one relevant trait is evident:the pervasive use of computational intelligence tools.
基金This work was supported by the National Natural Science Foundation of China(No.51777077)Thai Nguyen University of Technology(TNUT),Thai Nguyen,Vietnam.
文摘This study proposes an optimized model of a micro-energy network(MEN)that includes electricity and natural gas with integrated solar,wind,and energy storage systems(ESSs).The proposed model is based on energy hubs(EHs)and it aims to minimize operation costs and greenhouse emissions.The research is motivated by the increasing use of renewable energies and ESSs for secure energy supply while reducing operation costs and environment effects.A general algebraic modeling system(GAMS)is used to solve the optimal operation problem in the MEN.The results demonstrate that an optimal MEN formed by multiple EHs can provide appropriate and flexible responses to fluctuations in electricity prices and adjustments between time periods and seasons.It also yields significant reductions in operation costs and emissions.The proposed model can contribute to future research by providing a more efficient network model(as compared with the traditional electricity supply system)to scale down the environmental and economic impacts of electricity storage and supply systems on MEN operation.
基金Qinchuangyuan Cited High-level Innovation and Entrepreneurship Talents Project under(Grant No:2021QCYRC4-36)National Natural Science Fundation of China(Grant No.:72173095).
文摘The increasing penetration of renewables in power systems urgently entails the utilization of energy storage technologies.As the development of energy storage technologies depends highly on the profitability in electricity markets,to evaluate the economic potentials for various types of energy storage technologies under the compre-hensive market environment is of great significance.To this end,this study aims at conducting a quantitative analysis on the economic potentials for typical energy storage technologies by establishing a joint clearing model for electric energy and ancillary service(AS)markets considering the operating features of energy storage systems(ESSs).Furthermore,a test system is adopted for numerical analysis that accurately represents for the real-world operation characteristics of power systems in China,with which the market prices,and operation schedules and profitability of ESSs are comparatively studied.The proposed methodology and results could provide benefi-cial references for the modifications on electricity markets and the development of ESSs towards the increasing penetration of renewables in power systems.
文摘One purpose of stimulating financing and investment through private capital is to absorb a higher proportion of renewables and promote renewable industry development.This paper first reviews the current overall situation of renewables financing and investment,and further analyzes the policy environment with respect to the development plan,regulation and special funds.Based on the analysis of the status quo,the paper then discusses the internalities and the externalities that have driven the changes of private capital investment in renewable energy projects,illustrated by a strength,weakness,opportunity and threat(SWOT)analysis.An ideal financing model,public-private partnership and distributed energy resource pattern are analyzed to identify key arrangements and design proper development schemes for both private investors and the government.If China can overcome the defects and obstacles in a reasonable and orderly fashion,the financing and investment problem of China’s renewables industry will be solved in many ways.Private capital in China’s renewable energy market will bring great incentive if the entire industry can select some promising sub-industries in the renewables sector and choose some appropriate operation modes.
基金supported by the Fundamental Research Funds for the Central Universities(Zhejiang University NGICS Platform)the Zhejiang Provincial Public Welfare Technology Application Research Project(No.LGJ21E070001)。
文摘In recent years,rumors have been shown to have a significant impact on individual and societal activities.As renewables play an increasingly significant role in electricity markets,certain rumors may deviate the bidding behavior of market entities and eventually affect the performance of market operations.In this study,we attempt to reveal the general threats caused by rumors in the context of day-ahead electricity markets considering the integration of volatile renewables.First,we model the propagation of rumors in the societal system considering the weight of propagation resistance,which principally reflects the communication accessibility of market entities.Second,we develop an integrated two-layer network model to uncover the inherent coupling mechanism between market operations and rumor propagation.In particular,the role of electricity market operations on rumor propagation is characterized by changes in the truthfulness of rumors associated with electricity prices.The rumors,in turn,affect the bidding quantities of market entities in electricity market operations.Finally,numerical experiments are conducted on modified IEEE 6-bus and 118-bus systems.The results demonstrate the potential threats of rumors to electricity market operations with different penetration levels of renewables.
基金supported by the National Natural Science Foundation of China“Quantitative characterization of lacustrine shale oil mobility based on nano-scale oil-rock interactions”(No.42172180)Science and Technology Research Project for the China National Petroleum Corporation“Source-reservoir characteristics and sweet spot evaluation for terrestrial shale oil in China”(No.2021DJ1802)。
文摘0 INTRODUCTION Throughout human history,three major energy transitions have occurred:from burning wood in primitive times to using coal in 18th Century,then to oil and gas in 20th Century,and to the renewable energy revolution in the 21st Century(Zou et al.,2023).The three transitions have three characteristics in common:shifted from nonrenewable to renewable energy,from“resource-centric”to a“technology-centric”,and from“high-carbon fossil”to“net-zero”.
文摘The rapid growth in available network bandwidth has directly contributed to an exponential increase in mobile data traffic,creating significant challenges for network energy consumption.Also,with the extraordinary growth of mobile communications,the data traffic has dramatically expanded,which has led to massive grid power consumption and incurred high operating expenditure(OPEX).However,the majority of current network designs struggle to efficientlymanage a massive amount of data using little power,which degrades energy efficiency performance.Thereby,it is necessary to have an efficient mechanism to reduce power consumption when processing large amounts of data in network data centers.Utilizing renewable energy sources to power the Cloud Radio Access Network(C-RAN)greatly reduces the need to purchase energy from the utility grid.In this paper,we propose a bandwidth-aware hybrid energypowered C-RAN that focuses on throughput and energy efficiency(EE)by lowering grid usage,aiming to enhance the EE.This paper examines the energy efficiency,spectral efficiency(SE),and average on-grid energy consumption,dealing with the major challenges of the temporal and spatial nature of traffic and renewable energy generation across various network setups.To assess the effectiveness of the suggested network by changing the transmission bandwidth,a comprehensive simulation has been conducted.The numerical findings support the efficacy of the suggested approach.
基金supported by Universiti Teknologi PETRONAS and the Institute of Technology PETRONAS Sdn.Bhd.(ITPSB)through the Graduate Assistantship Scheme。
文摘Photoreforming is an emerging photocatalytic process that converts organic waste into hydrogen H2 using solar energy,offering a dual solution for waste valorization and sustainable fuel production.This review comprehensively examines the fundamental mechanisms of photoreforming,emphasizing the critical role of photocatalyst design in optimizing hydrogen evolution.Key criteria for effective photocatalysts including suitable band edge positions,broad spectrum solar absorption,and photostability are systematically analyzed alongside advances in heterojunction engineering and defect modulation.The review further explores diverse waste-derived feedstocks,such as biomass:alcohols,saccharides,lignin and plastics:PET,PLA,polyolefins,highlighting substrate,specific challenges and pretreatment strategies.Despite progress,challenges like catalyst deactivation,limited visible-light utilization,and scalability persist.Future directions advocate for robust photocatalyst engineering,mechanistic insights into charge dynamics,and scalable reactor designs to realize photoreforming’s potential as a sustainable hydrogen production technology.
基金Higher Education Commission(HEC)of Pakistan for financial support under grants#377-IPFP-Ⅱ/Batch-1st/SRGP-NAHE/HEC-2022-27 along with ASIP-Support Award Letter#ASIP/R&D/HEC/2024/10006/83387/127。
文摘This insightful review explores the electrochemical principles and energy potential of electrocatalytic water splitting(EWS).It highlights recent advancements,identifies key challenges,and underscores the pivotal role of EWS in enabling the transition to sustainable energy systems.This work contextualizes the significance of green hydrogen in global decarbonization pathways and examines the historical progression of electrocatalysis.The fundamental thermodynamics and mechanistic pathways governing both the hydrogen and oxygen evolution reactions(HER and OER)are analyzed,highlighting energy barriers and rate-determining steps.Various electrode architectures and electrochemical cell configurations are evaluated,including a comparative assessment of key electrolyzer technologies and their performance characteristics.Furthermore,we critically examine recent advances and persistent limitations across the landscape of electrocatalysts,spanning noble metal-based materials,earth-abundant transition metal compounds,and emerging materials.Design principles and mechanistic insights drawn from electronic structu re modulation,defect engineering,doping strategies,and na noscale morphology control are elucidated to establish robust structure-property-performance relationships.Major challenges including sluggish oxygen evolution kinetics,catalyst degradation mechanisms,and the integration of devices with intermittent renewable energy sources are thoroughly examined.This work also debates advanced strategies such as hybrid photoelectrochemical systems,flexible device architectures,and the direct utilization of non-traditional water sources(e.g.,seawater,wastewater)as promising pathways for future development.Finally,it is specifically distinguished by its critical focus on bridging the gap between fundamental electrocatalysts development and practical system-level integration,addressing the challenges of scalability and deployment under industrially relevant conditions.This comprehensive review provides a strategic outlook and identifies key scientific priorities for optimizing EWS systems toward efficient,robust,and scalable hydrogen generation.
基金supported by Natural Science Foundation of Shanghai,under the Shanghai Action Plan for Science,Technology and Innovation(22ZR1464800).
文摘Driven by the global energy transition and carbon neutrality targets,alkaline water electrolysis has emerged as a key technology for coupling variable renewable generation with clean hydrogen production,offering considerable potential for absorbing surplus power and enhancing grid flexibility.However,conventional control architectures typically treat the power converter and electrolyzer as independent units,neglecting their dynamic interactions and thereby limiting overall system performance under practical operating conditions.This review critically examines existing control approaches,ranging from classical proportional-integral schemes to model predictive control,fuzzy-logic algorithms,and data-driven methods,evaluating their effectiveness in managing dynamic response,multivariable coupling,and operational constraints as well as their inherent limitations.Attention is then focused on the performance requirements of the hydrogen-production converter,including current ripple suppression,rapid transient response,adaptive thermal regulation,and stable power delivery.An integrated co‑control framework is proposed,aligning converter output with electrolyzer demand across steady-state operation,variable renewable input,and emergency shutdown scenarios to achieve higher efficiency,extended equipment lifetime,and enhanced operational safety.Finally,prospects for advancing unified control methodologies are outlined,with emphasis on constraint-aware predictive control,machine-learning-enhanced modeling,and real‑time co‑optimization for future alkaline electrolyzer systems.
文摘The long-standing use of portable toilet cubicles by residents of Shanghai’s narrow,labyrinthine alleys came to an end in September 2025 after the city largely finished building public toilets to make up their lack of sanitation facilities.The project,targeting 14,082 households,started last year.
