Jayamurugan Mookkan, Saravanan Kaliyaperumal, Z. M. S. Elbarbary
et al.
In order to increase the application of renewable energy sources in the hybrid electrical vehicle application and also for zero tailpipe emission, a typical DC power converter interface in addition of effective control of power flow is very important. On that aim, a novel four port dc-dc power converter with bidirectional power flow is proposed to integrate the two input ports for photovoltaic (PV) and battery to two output ports for motor load and light load. The MPBC is customized for operating in buck and boost states with power flow control in both directional through changing the switching combinations. This system is implemented in hybrid e-vehicles (HEVs), where different level of dc voltages at battery and motor needs to be connected with the capability of bi-directional flow of power in regenerative action of vehicle to charge the battery. The different states of operation, steady state analysis, control scheme to regulate the power are presented. Power loss analysis is carried out to do proper design with more efficiency. The proposed converter simulation is done using MATLAB/Simulink to verify the validity of design, its behaviors and hardware response in different states of operation.
Renewable energy connected modular multilevel converter high-voltage direct-current (MMC-HVDC) system should have the capability of fault ride-through when the AC grid fails. However, it is difficult to quickly and reliably achieve fault ride-through via cooperative control if there is no high-speed communication between renewable energy and MMC-HVDC converters. Additionally, the droop coefficient in traditional voltage drop control is set to a linear constant, which makes it difficult to fast match under different fault conditions and results in a longer step delay, leading to high voltage operation of the DC system during the fault. Aiming at the existing problems mentioned above, the dynamic characteristics of the DC system and the principles of traditional voltage drop control are analyzed, which provides a basis for fast power matching on both sides of the DC system. Then, a fault ride-through control based on fast matching power for renewable energy connected MMC-HVDC is proposed. Finally, simulations based on PSCAD/EMTDC show that fault ride-through capability is reliable by using the proposed control method. Compared with traditional voltage drop control, the proposed control method significantly reduces the step delay, limits the rise of DC voltage and achieves fast and reliable fault ride-through.
In this article, we demonstrate CdSe–CuSbSe2-based double junction two-terminal tandem solar cells simulated with SCAPS-1D. The highest performance of the tandem cell has been confirmed by optimizing the electrical and optical properties of the window, top absorber, CdSe (bandgap 1.7 eV), bottom absorber, CuSbSe2 (bandgap 1.08 eV), and back surface layers. In addition, the effect of different parameters such as thickness, doping, and defect density of different layers has been investigated in detail. With the optimized condition, the modeled CdSe–CuSbSe2 double-junction two-terminal tandem solar cell displays a noticeable efficiency of 42.64% with an open-circuit voltage of 2.09 V, short-circuit current density of 24.09 mA/cm2, and fill factor of 84.36%, respectively. These results are highly propitious for the construction of all-chalcogenide–based high-performance tandem photovoltaic cells in the future.
А.H. Tkachuk, A.A. Humeniuk, O.O. Dobrzhansky
et al.
The article examines modern approaches to improving the energy efficiency of electric drives in the context of implementing the concept of smart energy networks (Smart Grid). Particular attention is given to the integration of electric drives as active participants in the energy balance, capable not only of consuming energy but also of adaptively regulating their operating modes in accordance with network parameters, load conditions, and the state of renewable energy sources. The study emphasizes the feasibility of using intelligent control systems that ensure high-quality regulation and reduced energy consumption under dynamically changing external conditions. Methods of energy consumption optimization based on adaptive control of variable-frequency drives are analyzed. The principles of using load forecasting algorithms are considered, enabling the formation of optimal operating profiles in advance and preventing peak overloads in the grid. The potential of regenerative operating modes, which allow excess energy during braking or speed reduction to be returned to the grid or local storage systems, is highlighted. This approach improves the overall efficiency of electric drive systems and reduces power losses. The results of simulation modeling performed in MATLAB/Simulink, using adaptive regulators and load models, confirm the effectiveness of the proposed strategies. It has been established that the application of intelligent control algorithms reduces the electricity consumption of electric drives compared to traditional control methods, increases the power factor, and decreases harmonic distortion levels in the grid by 25–30 %. Additionally, it is demonstrated that the use of adaptive regulators ensures system stability even under varying motor parameters and external disturbances. The practical implementation of such solutions is feasible in a wide range of applications: industrial production lines, electric transport systems, and integrated energy complexes with renewable sources. This opens new prospects for the development of energy-efficient Smart Grid systems with a high level of flexibility, reliability, and self-recovery capability after disturbances. The proposed approaches contribute to shaping a new paradigm of electric drives focused on minimizing energy losses and enhancing the overall efficiency of modern power systems.
Alfonso J Carrillo, María Balaguer, Cecilia Solís
et al.
Nanoparticle exsolution is a powerful technique for functionalizing redox oxides in energy applications, particularly at high temperatures. It shows promise for solid oxide fuel cells and electrolyzers. However, exsolution of other chemistries like metal oxides is not well studied, and the mechanism is poorly understood. This work explores oxide exsolution in PrBa _1− _x Co _2 O _6− _δ ( x = 0, 0.05, 0.1, 0.15) double perovskites, practiced electrodes in proton ceramic fuel cells and electrolyzers. Oxide exsolution in PrBa _1− _x Co _2 O _6− _δ aimed at boosting the electrocatalytic activity and was evaluated by varying intrinsic materials-related properties, viz. A-site deficiency and external parameters (temperature, under fixed time, and p O _2 = 10 ^−5 atm conditions). The materials were analyzed with conventional characterization tools and synchrotron-based small-angle x-ray scattering. Unlike metal-nanoparticle exsolution, increasing the A-site deficiency did not enhance the extent of oxide-nanoparticle exsolution, whereas larger nanoparticles were obtained by increasing the exsolution temperature. Combined Raman spectroscopy and electron microscopy analysis revealed that BaCoO _3 , Co _3 O _4 , and amorphous BaCO _3 nanoparticles were formed on the surface of the double perovskites after the reductive treatments. The present results demonstrate the complexity of oxide-nanoparticle exsolution in comparison with metal-nanoparticle exsolution. Further materials screening and mechanistic studies are needed to enhance our understanding of this method for functionalizing proton ceramic electrochemical cells (PCEC) electrodes.
Production of electric energy or power. Powerplants. Central stations, Renewable energy sources
The article consists of two main parts: theoretical and empirical. The first presents the opinions of authors representing International Political Economy who question the assumption that the transformation of the energy sector can be based only on the market mechanism. They justify that the most favourable conditions for carrying out structural changes going in the direction of gradual reduction of fossil fuels and increasing the share of alternative sources in energy production exist in democratic countries where the state performs social-economic functions and engages in the promotion of clean technologies in the energy sector. The empirical analysis assesses the advancement of structural changes in energy production globally and in the group of the 15 largest producers by the share of raw materials used in 2000-2019. The study also includes changes in the subject and object structure of exports and imports of energy raw materials. The analysis shows that diversification of energy sources was progressing, but mainly concerned the share of coal, oil and gas in its production. A negative phenomenon was the increase in the share of coal in energy production in the global economy from 22.8 to 27.1%. Contributing to this were: China, Australia, Indonesia, India and Russia. In the EU, the results of the transformation of the energy sector, compared to other countries, were exceptionally good. The share of renewable raw materials in energy production increased from 11.0 to 33.4%.
Referring to the impact of the energy sector transformation and changes in energy markets on the global balance of economic power, the authors concluded that fossil raw material resources, which are concentrated in a small group of countries, give them great opportunities to directly influence the formation of their world prices, the situation in other markets and the overall situation in the global economy through the transmission of inflation, exchange rate fluctuations and imbalances in the balance of payments. In 2000-2019, Russia strengthened its dominance in global energy commodity markets by increasing its share in world exports from 10 to 12.7%, against 9.1% of the USA, 8.8% of the EU-28, 7.5% of Saudi Arabia and 6.05% of Australia. Russia's important assets as an energy power are its well-developed oil and gas transport infrastructure covering Europe and Asia, the strong monopolistic position of Gazprom and other companies on the fossil fuel markets and the EU's high dependence on imports of energy resources from Russia. The new geopolitical situation has a major impact on changing the priorities of the energy policy of the EU and the US, as well as of the countries dependent on raw material imports from Russia. The process of transformation of the energy sector may be dynamised, which will weaken Russia's position.
Fabricating non-noble metal-based carbon air electrodes with highly efficient bifunctionality is big challenge owing to the sluggish kinetics of oxygen reduction/evolution reaction (ORR/OER). The efficient cathode catalyst is urgently needed to further improve the performance of rechargeable zinc-air batteries. Herein, an activation-doping assisted interface modification strategy is demonstrated based on freestanding integrated carbon composite (CoNiLDH@NPC) composed of wood-based N and P doped active carbon (NPC) and CoNi layer double hydroxides (CoNiLDH). In the light of its large specific surface area and unique defective structure, CoNiLDH@NPC with strong interface-coupling effect in 2D-3D micro-nanostructure exhibits outstanding bifunctionality. Such carbon composites show half-wave potential of 0.85 V for ORR, overpotential of 320 mV with current density of 10 mA cm−2 for OER, and ultra-low gap of 0.70 V. Furthermore, highly-ordered open channels of wood provide enormous space to form abundant triple-phase boundary for accelerating the catalytic process. Consequently, zinc-air batteries using CoNiLDH@NPC show high power density (aqueous: 263 mW cm−2, quasi-solid-state: 65.8 mW cm−2) and long-term stability (aqueous: 500 h, quasi-solid-state: 120 h). This integrated protocol opens a new avenue for the rational design of efficient freestanding air electrode from biomass resources.
Abstract The increasing amount of distributed renewable energy (DRE) is participating in grid‐connected operation as an important unit of the virtual power plant (VPP) aggregation. VPP also contains a variety of flexible resources such as demand response (DR), energy storage (ES), and fuel cell (FC). How to achieve efficient energy utilization while reducing carbon emissions and resisting the risk of failure caused by extreme weather has attracted widespread attention. In this article, a cooperative game‐based low‐carbon scheduling model for multi‐VPPs under the consideration of typhoon‐induced grid outage risks is proposed. First, a cooperative game mechanism for multi‐VPPs is constructed. And a bi‐level model of multi‐VPPs low‐carbon scheduling is built under the framework of electricity‐carbon trading markets. Second, the bi‐level scheduling model is linearized based on the Strong Duality Theorem and Karush‐Kuhn‐Tucker (KKT) condition. Then, the dispatch scheme of each VPP under the cooperative game form is obtained. Finally, simulations are performed to verify the validity of the proposed model. The results show that the economic and low‐carbon performance of multi‐VPPs can be improved by applying the cooperative game, which can also enhance the power system ability of resisting line faults.
This manuscript focuses on analyzing the growth dynamics of the Central Taiwan Science Park (CTSP) and Silicon Glen in Scotland with a specific emphasis on their approaches to energy, environmental conservation, and economic management. The objective is to provide insights into their sustainable development strategies. In terms of energy, CTSP addresses Taiwan’s energy security and green transformation challenges, while Silicon Glen concentrates on Scotland’s wind energy generation technologies. Both regions prioritize the advancement of renewable energy sources and smart grid technologies. In the realm of environmental conservation, both CTSP and Silicon Glen prioritize environmental protection and sustainability by implementing rigorous environmental monitoring measures. Regarding economic management, CTSP and Silicon Glen serve as vital technology industry hubs in Taiwan and Scotland, respectively, attracting a multitude of high-tech and startup enterprises. This growth is facilitated through various means, including policy support, access to research resources, and robust infrastructure. This manuscript presents a comparative analysis of these two industrial parks, focusing on their environmental and economic management strategies. It aims to elucidate the principles underpinning the sustainable development and economic growth of industrial parks, offering valuable insights to decision-makers and stakeholders involved in the planning of sustainable industrial parks.
Mohamed Mostafa Elsaied, Walid Helmy Abdel Hameed, Hany M. Hasanien
Abstract This paper presents a three‐area system tied together with tie lines. During the intervals of power mismatch, the system frequency deviates beyond the nominal value with an oscillatory response and the system may go to instability mode. The main purpose of the control strategy is optimizing the frequency fluctuations of the three areas and the deviations in the three tie line powers. This is achieved by three controllers as follows: the Tilt‐Integral‐Derivative (TID) controller, the Fractional Order Proportional‐Integral‐Derivative (FOPID), and the Proportional‐Integral‐Derivative (PID) controller. The three controllers are optimized by a new metaheuristic optimization algorithm based on the jellyfish behaviour in the ocean called the Jellyfish Search (JS) Optimizer. To prove the algorithm validity, it is compared with previous optimization techniques that have been applied to the study field such as Grey Wolf Optimization (GWO) algorithm and Genetic Algorithm (GA). Furthermore, renewable energy sources are implemented in the system such as wind energy and photovoltaic based on real data. Finally, energy storage devices (ESDs) like superconducting magnetic energy storage (SMES), capacitor energy storage (CES), and battery energy storage (BES) are implemented to improve the system behaviour due to the intermittent behaviour in the renewable sources.
Fauzi Yusupandi, Hary Devianto, Pramujo Widiatmoko
et al.
Intermediate temperature solid oxide fuel cell (IT-SOFC) provides economic and technical advantages over the conventional SOFC because of the wider material use, lower fabrication cost and longer lifetime of the cell components. In this work, we fabricated electrolyte-supported IT-SOFC using low-cost materials such as calcia-stabilized zirconia (CSZ) electrolyte fabricated by dry-pressing, NiO-CSZ anode and Ca3Co1.9Zn0.1O6 (CCZO) cathode produced through brush coating technique. According to the XRD result, the monoclinic phase dominated over the cubic phase, and the relative density of the electrolyte was low but the hardness of the CSZ electrolyte was close to the hardness of commercial 8YSZ electrolyte. The performance of the single cell was performed with hydrogen ambient air. An open-circuit voltage (OCV) of 0.43, 0.46, and 0.45 V and a maximum power density of 0.14, 0.50, and 1.00 mW/cm2 were achieved at the operating temperature of 600, 700, and 800 °C, respectively. The ohmic resistance of the cell at 700 and 800 °C achieved 81.5 and 33.00 Ω, respectively due to the contribution of thick electrolyte and Cr poisoning in electrodes and electrolyte
Bogdan Marinescu, Oriol Gomis-Bellmunt, Florian Dorfler
et al.
The concept of Virtual Power Plant (VPP) has arisen over a decade ago from the relatively low competitiveness of the back then emerging non-dispatchable RES. A set of smaller generators imitates the behavior of large synchronous generators. So far, static aspects such as generation or slow dynamics have been of interest, as it is the case for the zonal secondary frequency control scheme in Spain, which can be viewed as a VPP. However, considering dynamic aspects is of high importance, especially to further increase the current penetration level of Renewable Energy Sources (RES). Indeed, one should deal with the full participation of RES in grid ancillary services. This means not only to get some positive impact on grid voltage and frequency dynamics but to bring concepts which allow integrating RES to existing secondary regulation schemes on the same level as classic synchronous generators. For that, we propose here a new concept called Dynamic VPP (DVPP) which fully integrates the dynamic aspects at all levels: locally (for each RES generator), globally (for grid ancillary services and interaction with other close-by elements of the grid) and economically (for internal optimal dispatch and participation in electricity markets). A DVPP is a set of dispatchable and non-dispatchable RES along with a set of common control and operation procedures. The latter procedures include the choice of dispatchable and non-dispatchable RES constituting the DVPP, the control of DVPP generators for local objectives and participation of the DVPP as a single unit in ancillary services (especially in case of loss of natural resources - e.g., wind, sun - on a part of the DVPP), the limitation of the risk of adversely interaction with close-by elements and the feasibility in both current power systems scenarios and future ones with large share of RES. This new DVPP framework and approaches developed for its implementation allows ensuring optimal operation of a mixed portfolio of dispatchable and non-dispatchable RES generators for planning, participation to the markets and real-time control. For the control, all time-scale dynamics are considered to improve RES management (internal re-dispatch inside the DVPP to take advantage of dispatchable/non-dispatchable nature of each RES and to optimally manage the lack of natural resources in some regions of the DVPP) and their participation to grid ancillary services. Concrete structures of DVPP as well as ways to address the other control and economical aspects will be shown. This new DVPP concept is now under development in the H2020 POSYTYF project (<uri>https://posytyf-h2020.eu/</uri>).