Supply Configuration Research Articles

Electricity supply configurations for green hydrogen hubs: A European case study on decarbonizing urban transport

In this study, a techno-economic analysis tool for conducting detailed feasibility studies on the deployment of green hydrogen hubs for fuel cell bus fleets is developed. The study evaluates and compares five green hydrogen hub configurations' operational and economic performance under a typical metropolitan bus fleet refuelling schedule. Each configuration differs based on its electricity sourcing characteristics such as the mix of energy sources, capacity sizing, financial structure, and grid interaction. A detailed comparative analysis of distinct green hydrogen hub configurations for decarbonising a fleet of fuel-cell buses is conducted. Among the key findings is that a hybrid renewable electricity source and hydrogen storage are essential for cost-optimal operation across all configurations. Furthermore, bi-directional grid-interactive configurations are the most cost-efficient and can benefit the electricity grid by flattening the duck curve. Lastly, the paper highlights the potential for cost reduction when the fleet refuelling schedule is co-optimized with the green hydrogen hub electricity supply configuration.

Game Theory Applications in Equilibrium Water Pricing of Multiple Regional Sources and Users

China has been facing a contradiction between its water supply and demand for a long time, and it is urgent that it builds a “water-saving society”. Previous research on water pricing mainly focused on the policy level, only considering the supply and demand sides and ignoring the participation of local governments. Due to the inconsistent approval mechanisms, different times of cost formation, and lack of a scientific pricing relationship between multiple water sources and multiple users, with the current water pricing in China, it is difficult to solve the complex problem of water resource allocation. This study aimed to promote the qualitative supply of water and the reuse of reclaimed water, achieve a high-quality and low-cost water supply, and explore the role of water-pricing mechanisms in the regulation of multi-source water supply configurations. The mechanism of regulation is constructed for the complex, multi-source, multi-user water resource system, and a three-party game model is established among local governments, water supply enterprises, and water users. A reasonable pricing system with a rational price relationship is obtained, and Pinghu City in Zhejiang Province is taken as the research area. The prices of the external water supply to residential users, non-resident users, and special users are 4.48 CNY/m3, 6.28 CNY/m3, and 7.12 CNY/m3. The external supply prices for resident users, non-resident users, and special users are 3.81 CNY/m3, 5.25 CNY/m3, and 6.05 CNY/m3. The external supply price for non-resident users is 2.62 CNY/m3 for reclaimed water. The results of the study showed that when the government’s contribution did not exceed the amount that it would have been without the inclusion of recycled water and the annual payment of water users did not exceed their ability to pay, the income of water suppliers increased by 69%. The three balanced objectives of rational water resource configuration by the local government, reasonable profit for the water supply enterprise, and reasonable payment by water users have been achieved. This study provides theoretical and methodological support for the implementation of water pricing for multi-source and multi-user water supplies in water-scarce areas.

Organizational culture’s influence on supply chain performance analysis with fuzzy grey cognitive maps

PurposeThis paper applies fuzzy grey cognitive maps (FGCM) to support multicriteria group decision making (GDM) on supply chain performance (SCP) considering the role of organizational culture as a moderating factor.Design/methodology/approachThis paper follows the quantitative axiomatic prescriptive model-based research. It introduces a MGDM model that relies on the SCOR® model performance attributes and Hofstede’s cultural dimensions. The proposal is underpinned by the soft computing technique of FGCM, aimed at addressing the inherent subjectivity associated with evaluating the culture-performance relationship within supply chains.FindingsThe FGCM-based model proposes a management matrix tool for supporting SPC management. It results in a graphical representation that deconstructs SCP and organizational culture into key elements and provides directives for action plans that align improvement efforts. An illustrative application is presented to guide and promote the model’s application in different configurations of supply chains.Practical implicationsThis model offers valuable insights into addressing the impact of organizational culture on decision-making related to SCP. Additionally, it facilitates scenario simulation. The management matrix visually illustrates how each performance attribute is influenced by each cultural dimension on a quantitative scale. It also ranks these attributes based on the overall level of influence they receive from culture.Originality/valueThe study provides a unique outlook on the use of FGCMs to support the SCP decisional process by detailing and accounting for the influence of organizational culture. This is done through the development of a novel matrix that allows for visual management and benchmarking.

A peer-to-peer energy trading market framework for single buyer model: An integration of decentralised finance instruments and cooperative game model

Single Buyer (SB) model has gained traction in many Southeast Asia, Middle Eastern, and North African countries for its blend of centralisation and controlled competition. The semi-liberalised regulatory environment has hindered the integration of cogeneration or combined heat and power (CHP) as a prosumer within the electricity value chain, despite its pivotal role in enhancing energy efficiency. There is a disconnection in the existing literature as electric supply configurations and enablement of peer-to-peer (P2P) electricity trading are individually studied. There also lacks the studies addressing electricity as a special commodity and its compatibility with the market. This paper bridges the research gaps by proposing a P2P energy trading market framework that integrates decentralised finance (DeFi) instruments and a cooperative game model. Malaysia, which implements the SB model in its electric supply structure, is selected for a case study. The comprehensive framework develops (1) a stableswap hybrid function automated market maker (HFMM) decentralised exchange (DEX) for P2P trading, (2) a mixed-integer linear programming (MILP) optimisation model to determine the optimal operational strategy with minimised total annualised cost (TAC) of the system, and (3) an allocation scheme based on a cooperative game model to gauge the individual and coalitional cost savings allocations. Overall, this study presents a novel approach to addressing the challenges with innovating the SB model, while also fostering competitions among prosumers. The SB structure of Malaysia is briefly inspected, and the proposed framework is expected to contribute to the growth of macro-level CHP integration in the nation's energy planning.

Research on Capacity Configuration for Green Power Substitution in an Isolated Grid Containing Electrolytic Aluminum

The deployment of a green power alternative within an isolated network, powered by renewable energy sources, in the “Three North” region of China can facilitate the substitution of high-energy-consuming industrial loads with green power. However, an inadequate power supply configuration may lead to economic and reliability issues. To address this problem, effective capacity allocation within the green power alternative isolated network is proposed. The capacity allocation process starts with the design of a network structure that aligns with local conditions. Subsequently, a capacity allocation model is developed, considering economic factors, renewable energy utilization efficiency, and system reliability. The gray wolf optimizer is enhanced to establish a capacity allocation method for the green power alternative isolated network. This method is then employed to simulate and assess the performance of the network. The results indicate that the green alternative isolated grid can successfully facilitate green power substitution, satisfying the energy requirements of the loads.

Aboveground hydrogen storage – Assessment of the potential market relevance in a Carbon-Neutral European energy system

Hydrogen storage is expected to play a crucial role in the comprehensive defossilization of energy systems. In this context, the focus is typically on underground hydrogen storage (e.g., in salt caverns). However, aboveground storage, which is independent of geological conditions and might offer other technical advantages, could provide systemic benefits and, thereby, gain shares in the hydrogen storage market. Against this background, this paper examines the market relevance of aboveground compared to underground hydrogen storage. Using the open-source energy system model and optimization framework of Europe, PyPSA-Eur, the influence of geological independence, storage cost relations, and technical storage characteristics (i.e., efficiencies) on mentioned market relevance of aboveground hydrogen storage are investigated. Further, the expectable market relevance based on current cost projections for the future is assessed. The studies show that in terms of hydrogen capacities, aboveground hydrogen storage plays a considerably smaller role compared to underground hydrogen storage. Even when assuming comparatively low aboveground storage cost, it will not exceed 1.7% (1.9TWhH2,LHV) of total hydrogen storage capacities in a cost-optimal European energy system. Regarding the amounts of annually stored hydrogen, aboveground storage could play a larger role, reaching a maximum share of 32.5% (168TWhH2,LHVa-1) of total stored hydrogen throughout Europe. However, these shares are only achievable for low cost storage in particularly suited energy system supply configurations. For higher aboveground storage costs or lower efficiencies, shares drop below 10% sharply. The analysis identifies some especially influential factors for achieving higher market relevance. Besides storage costs, the demand-orientation of a particular aboveground storage system (e.g., hydrogen storage at demand pressure levels) plays an essential role in market relevance. Further, overall efficiency can be a beneficial factor. Still, current projections of future techno-economic characteristics show that aboveground hydrogen storage is too expensive or too inefficient compared to underground storage. Therefore, to achieve notable market relevance, rather drastic cost reductions beyond current expectations would be needed for all assessed aboveground hydrogen storage technologies.

The Disruptive Innovation Impact of Supply and Demand Matching in Digital Platforms Using Fuzzy-Set Qualitative Comparative Analysis Methodology: Evidence from China

Practice shows that digital platforms could enhance disruptive innovation. Given that digital platforms have always encountered imbalance problems, this study intended to explore which factor configurations could promote disruptive innovation sustainably from the perspective of supply and demand matching. This study constructed a theoretical framework referring to the TOE framework. Based on 25 questionnaires from China, the fuzzy-set qualitative comparative analysis (fsQCA) method was used to explore the configurations of disruptive innovations. This study found the following: (1) None of the five factors in the dimensions of technology, organization, or environment could constitute a necessary condition for enabling disruptive innovation alone. (2) There were four supply and demand matching configurations that could lead to highly disruptive innovation. Based on the homogeneous characteristics of the results, the four paths were divided into “technology-organization driven transition” types and “organization-environment collaborative transition” types. (3) Non-highly disruptive innovation included three specific configurations, all of which lacked the core conditions in technical and organizational dimensions, suggesting the importance of technical and organizational factors for disruptive innovation. This study provides guidance on supply and demand matching for platform enterprises to continuously create disruptive innovation. However, the data from China may limit the results’ applicability to a more expansive setting.

EPR核电厂主给水调节阀FUM280 增加冗余配置方案研究

EPR核电厂主给水调节阀FUM280 增加冗余配置方案研究

Effect of pressure and supply configuration on mixing efficiency through Venturi effect for co2/h2- ch4/h2 mixtures in Power-To-Gas process: CFD analysis

Introduction: The present article is one of the outcomes of the project “Desarrollo de un sistema “power to gas” (PTG) en el contexto de las fuentes de energía renovables y convencionales disponible en la Guajira” This project was carried out by the University of Antioquia and the University of La Guajira during the period 2019-2023. Problem: Efficiency and uniformity in gas mixing for Power-to-Gas applications are influenced by pressure varia- tions and supply configurations. Objective: To assess the impact of pressure variations and supply configurations on the efficiency of the Venturi mixing process, utilizing indicators such as the Z-factor and the coefficient of variation (CoV). Methodology: Numerical simulations were conducted for four mixer configurations. For CO2/H2 mixtures, pressures of 1 bar (case i) and 4 bars (case ii) were considered; for CH4/H2 mixtures, pressures of 3 bars (case i) and 35 bars (case ii) were studied. Results: As the inlet gas pressure increases, uniformity decreases for both mixtures. Horizontal H2 feeding improves CO2/H2 uniformity, while vertical feeding benefits CH4/H2 mixing. The mixer reduces CoV by an average of 80% for CO2/H2. For CH4/H2 mixtures at 3 bars, there is a 60% reduction, but at 35 bars, coefficients increase by 56%. Conclusion: Pressure and supply configuration significantly influence the mixing process, underscoring the impor- tance of considering these factors in Power-to-Gas applications. Originality: The study explores the Venturi mixing process in specific gas mixtures for Power-to-Gas applications. Limitations: The studied conditions and configurations may not encompass all possible scenarios in Power-to-Gas applications.

A Systematic Tri-level Demand-driven Supply-side Management Approach on Enhancing Building Energy Performance in an Educational Institution

The concept of demand-side management (DSM) is a ceaseless research topic craving an advanced, superior, and qualitative strategy for improving customers’ level of satisfaction with energy utilization. It encourages the active participation of prosumers and paves the way for sufficient energy proficiency. However, less attention is paid to accounting for consumers’ comfort and priorities. This paper presents a tri-level systematic approach for implementing demand-side and supply-side management at the consumer end. The proposed Tri-level Demand-Driven Supply-Side Management (TDD-SSM) framework commences with gathering knowledge on available loads in the department building block of a higher educational institution situated in the Madurai district of Tamil Nadu, India. The incorporated DSM technique follows strategic load categorization and load scheduling. Following that, a feasibility study on optimal sources is accomplished with Hybrid Optimization of Multiple Energy Resources software. The simulation is done to have a clear comparison in rendering a techno-enviro-economically feasible configuration of energy source to loads (with and without DSM). Ultimately, the framework concludes by picking the most promising energy configuration through the ideal computational multi-criteria decision-making–Preference Ranking Organization Method for Enrichment Evaluation II approach, which highlights the energy configuration of photovoltaic solar generation supply along with grid feeding loads after DSM incorporation and is found to be the best energy configuration under techno-enviro-economic criteria.

Mild hybrid energy dual-slope solar stills: Design and performance

The critical increase in the lack of available freshwater worldwide owing to different anthropogenic and natural causes has led mankind to seek serious solutions, such as the use of solar stills. This study shows the design and performance of a dual-slope solar still powered by a mild hybrid power supply system. Different power supply configurations were created for the solar still, and commercial phase change materials were incorporated into the prototype. The highest freshwater production rate in the active solar still (6.76 l/m2d) was obtained when power was supplied from the portable photovoltaic plant at the beginning of the test, with an associated cost per liter of produced water of 0.2218 USD. It was shown that phase change materials increased the heat retention time and optimized the energy supply in the solar still. However, their use did not result in lower freshwater production costs.

Power Sources for Unmanned Aerial Vehicles: A State-of-the Art

Over the past few years, there has been an increasing fascination with electric unmanned aerial vehicles (UAVs) because of their capacity to undertake demanding and perilous missions while also delivering advantages in terms of flexibility, safety, and expenses. These UAVs are revolutionizing various public services, encompassing real-time surveillance, search and rescue operations, wildlife assessments, delivery services, wireless connectivity, and precise farming. To enhance their efficiency and duration, UAVs typically employ a hybrid power system. This system integrates diverse energy sources, such as fuel cells, batteries, solar cells, and supercapacitors. The selection of an appropriate hybrid power arrangement and the implementation of an effective energy management system are crucial for the successful functioning of advanced UAVs. This article specifically concentrates on UAV platforms powered by batteries, incorporating innovative technologies, like in-flight recharging via laser beams and tethering. It provides an all-encompassing and evaluative examination of the current cutting-edge power supply configurations, with the objective of identifying deficiencies, presenting perspectives, and offering recommendations for future consideration in this domain.

Exergy analysis of pressure reduction, back pressure and intermittent air supply configuration of utilization/expansion stage in compressed air systems

Despite their many advantages, industrial compressed air systems are characterized by high energy consumption and very low energy efficiency. This is primarily due to the oversizing of pneumatic actuators, leading to excessive compressed air consumption in the utilization stage. Various methods have been proposed in the literature to address this issue, which can be classified into three groups: supply pressure reduction, back pressure increase, and intermittent power supply. However, no exergy analysis compares these methods in the utilization stage of a pneumatic system was performed. In this study, we conducted an exergy analysis to compare the exergy consumption and exergy savings of different pneumatic system configurations: the classic configuration, supply pressure reduction, back pressure increase, and intermittent power supply. The paper shows the most key places in CAS in terms of exergy losses, which result mainly from dead volumes, outlet loss and oversizing of components such as directional control valve, distributed pneumatic line and actuator. Losses in those components can amount to over 80% of input exergy and can be reduced even 3–9 times. Exergy evaluation of oversizing configurations showed that the highest exergy savings were obtained for a back pressure configuration (77%) and intermittent air supply (75%). The exergy savings for the pressure reduction configurations amounted to almost 50%. The paper presents mathematical models for several individual pneumatic components, including the actuator, directional control valve, muffler, pneumatic line and pressure reducer. The demonstrated mathematical model and exergy analysis can play a instrumental role in evaluating the exergy efficiency and optimization of a pneumatic system.

A novel gas supply configuration for hydrogen utilization improvement in a multi-stack air-cooling PEMFC system with dead-ended anode

The gas supply configuration would influence the reactant distribution, output performance, and durability of multi-stack proton exchange membrane fuel cells (PEMFCs). However, few researches have been conducted on optimizing the gas supply configuration. In this work, the hydrogen supply systems of two air-cooling PEMFC stacks under dead-ended anode (DEA) mode are connected in parallel and series configuration, and effects of configuration method on the performance, uniformity, and purging characteristics of these PEMFC stacks are studied. The experimental results show that series configuration provides higher power output at the expense of lower fuel utilization in comparison with parallel configuration. The main cause for the voltage degradation of PEMFCs systems under DEA mode is the accumulation of impurity gas in the outlet of PEMFC stack. Therefore, an optimized series gas configuration is proposed by adding a buffer tank and solenoid valves at the outlet of PEMFC system to purge and store the impurity gas. The optimized series configuration extends purging interval from 125 s to 800 s at the current density of 200 mA cm−2 without parasitic power. The fuel utilization has been improved from 97.51% (in series), 98.87% (in parallel) to 99.21% (in optimized series).

Optimal Design and Configuration Strategy for the Physical Layer of Energy Router Based on the Complex Network Theory

The energy router (ER) is key to realizing the coordinated management and efficient utilization of multiple forms of energy in Energy Internet. This paper proposes a novel design and configuration method for the physical layer of ER by using complex network theory. Firstly, an abstract model of the physical layer of ER is introduced according to its function, and important modules in the model are illustrated in details. Secondly, based on the electrical characteristics of ports, the community structure of the power networks inside ER is analyzed by the improved Girvan-Newman (GN) algorithm to design the independent bus systems (IBSs) and generate the network topology of the physical layer. Then, the optimization model of equipment configuration of the power supply and distribution systems of ER is developed considering the economy, utilization efficiency, and power supply reliability. Finally, two case studies demonstrate that the proposed strategy can effectively accomplish the module-level structure design and device configuration for the physical layer of ER.

Random decision forest (RDF) and crystal structure algorithm (CryStAl) for uncertainty consideration of RES & load demands with optimal design of hybrid CCHP systems

This manuscript proposes a multi-objective random development mode of hybrid Combined Cooling, Heating, And Power (CCHP) system, supply configuration, enclosing a turbine, cooler/heater, battery and storage tank, and photovoltaic/thermal collectors. The proposed optimal strategy is consolidation of Random Decision Forest (RDF) and Crystal Structure Algorithm (CryStAl), hence it is called RDF-CryStAl technique. The Power center models of power converters along with storage devices are create by assuming the characteristics of non-design elements. The annual value rate falls when system confidence levels drop and uncertainty is used. The yearly value savings rate is shown to be highly sensitive to the price of fossil-fuels as a result of the sensitivity analysis of economic-frontiers based on important economic factors. As a result, the inversion of star-collectors includes a robust impact of the turbine.

The spatially uneven effects of a desegregation education policy

The spatial, institutional and social configurations of school supply and demand are crucial aspects in understanding the various mechanisms of production and reproduction of socio-spatial inequalities in education. The same policy instruments may have different effects depending on the characteristics of local education markets and the dynamics of supply and demand in each of them. This article investigates how a policy designed to reduce school segregation in the city of Barcelona resulted in uneven effects in different catchment areas of the city, which are socially and educationally diverse. By comparing the effects of the same policy strategy in different territories, the article identifies four mechanisms that mediate and occasionally prevent the effectiveness of the policy instruments or their implementation procedures. Identifying these mechanisms is an important and necessary task when reviewing the existing policy design and adapting it to the particularities of local education markets.

Linking landscape structure and ecosystem service flow

Despite advances in understanding the effects of landscape structure on ecosystem services (ES), many challenges related to these complex spatial interactions remain. In particular, the integration of landscape effects on different components of the service provision chain (supply, demand, and flow) remains poorly understood and conceptualized. Here we propose a theoretical framework to further explore how the spatial flow of ES can vary according to landscape structure (i.e. composition and configuration) emphasizing the role played by the configuration of supply, demand, and neutral areas, as well as individual characteristics of ES (e.g., service rivalry). For this, we expand the discussion on how landscape changes can affect ES flows and propose a theoretical representation of ES flows variation led by different supply-demand ratios. Additionally, we expand this discussion by integrating the potential effects of neutral areas in the landscape as well as of supply/demand spatial overlap. This novel approach links the spatial arrangement (e.g. fragmentation, network complexity, matrix resistance) usually captured by landscape metrics, and ratios of ES supply and demand areas to potential effects on spatial flows of ES. We discuss the application of this model using widely studied ES, such as pollination, pest control by natural enemies, and microclimate regulation. Finally, we propose a research agenda to connect the presented ideas with other prominent research topics that must be further developed to support landscape management targeting ES provision. The prominence of ES science calls for contributions such as this to give the scientific community the opportunity to reflect on the underlying mechanisms of ES and avoid oversimplified spatial assessments.

Optimal operation scheduling of a PV-BESS-Electrolyzer system for hydrogen production and frequency regulation

As the green hydrogen industry develops, hybrid renewable power supply configurations emerge as a solution to increasing electrolyzer load factor. In particular, solar photovoltaics (PV) paired with Battery Energy Storage Systems (BESS) will provide a suitable option for continuous power supply as their investment costs continue to decline during the next decade. An opportunity arises to use the plant’s energy resources to provide grid services without hindering hydrogen production. Motivated by this, this paper presents a chance-constrained stochastic model for the optimal operation scheduling of a PV-BESS-Electrolyzer system participating in energy and ancillary services markets. Scenarios are used to account for uncertainty in solar power availability and energy content of the frequency regulation signal, and a degradation model is included to properly consider the effect of repeated battery cycling. Computational experiments using PJM market data and a realistic time frame show the benefits of the proposed model, achieving 10.2% more profits than the deterministic benchmark problem, while maintaining low failure rates in the provision of the regulation service and a similar hydrogen production compared to an off-grid standalone operation.

Modification of the Aeration-Supplied Configuration in the Biodrying Process for Refuse-Derived Fuel (RDF) Production

Biodrying is an essential part of the mechanical–biological treatment process that minimizes moisture content and simultaneously maximizes heating value for refuse-derived fuel (RDF) production. Although the mechanical separation process operates effectively in Thailand’s RDF production, high organic content levels and their degradation cause moisture contamination in RDF, producing wet RDF. Aeration is essential for an effective biodrying process, and can reduce RDF’s moisture content as well as increase its heating value. To maximize the biodrying effect, aeration should be optimized based on the waste conditions. This study proposes a modified aeration-supplied configuration for wet RDF biodrying. The aeration rate was modified based on the period within the biodrying operation; the first period is from the beginning until day 2.5, and the second period is from day 2.5 to day 5. The optimal aeration supply configuration was 0.5 m3/kg/day in the first period and then 0.3 m3/kg/day until the end of the process; this configuration yielded the greatest moisture content decrease of 35% and increased the low heating value of the biodried product by 11%. The final moisture content and low heating value were 24.07% and 4787 kcal/kg, respectively. Therefore, this optimal aeration-supplied configuration could be applied to meet the moisture content and low heating value requirements of the RDF production standard for Thailand’s local cement industry.