The study of Cyber-Physical System (CPS) has been an active area of research. Internet Data Center (IDC) is an important emerging Cyber-Physical System. As the demand on Internet services drastically increases in recent years, the power used by IDCs has been skyrocketing. While most existing research focuses on reducing power consumptions of IDCs, the power management problem for minimizing the total electricity cost has been overlooked. This is an important problem faced by service providers, especially in the current multi-electricity market, where the price of electricity may exhibit time and location diversities. Further, for these service providers, guaranteeing quality of service (i.e. service level objectives-SLO) such as service delay guarantees to the end users is of paramount importance. This paper studies the problem of minimizing the total electricity cost under multiple electricity markets environment while guaranteeing quality of service geared to the location diversity and time diversity of electricity price. We model the problem as a constrained mixed-integer programming and propose an efficient solution method. Extensive evaluations based on real-life electricity price data for multiple IDC locations illustrate the efficiency and efficacy of our approach.
ABSTRACT Due to a positive standard reaction Gibbs free energy (ΔrGmθ) of 237.1 kJ mol−1, electric energy input is indispensable for hydrogen production by conventional electrochemical water splitting. This energy requirement can be reduced by replacing the anodic oxygen evolution reaction to thermodynamic favorable small‐molecules oxidation reactions. In this work, anodic formaldehyde oxidation reaction (FOR) in alkaline media was paired with cathodic hydrogen evolution reaction (HER) in acidic media to establish a thermodynamically downhill system. The utilization of electrochemical neutralization energy in a hybrid alkaline‐acidic electrolyte configuration enables a further decrease in ΔrGmθ. Therefore, the resulting hybrid alkaline‐acidic formaldehyde‐proton fuel cell (FPFC) exhibits a significantly reduced ΔrGmθ of −101.5 kJ mol−1. A bifunctional Ru‐doped Cu catalyst (Ru─Cu NTs@CM) was designed and synthesized to simultaneously promote the kinetics of acidic HER and alkaline FOR, demonstrating superior catalytic activity and durability to pristine Cu and Ru catalysts. This catalyst enabled concurrent bipolar H2 production and electricity generation from the assembled FPFC, reaching a peak power density of 18.3 mW cm−2 at 53.4 mA cm−2. A combination of (quasi) in situ characterizations and theoretical calculations unveiled the important mechanistic role of Ru‐doping in enhancing the Cu catalyst's activity and stability.
Neo Rafifing, Alton Mabina, Leatile W. Rafifing
et al.
The rapid development of the Fourth Industrial Revolution is having diverse effects on underdeveloped nations, influencing them in various ways. Developed countries have an advantage over underdeveloped countries since they embraced industrialization earlier, widening the gap between them. This comprehensive survey paper examines the multifaceted landscape of industry 4.0 in supply chain, shedding light on the potential challenges and key value drivers in the context of a developing country. Findings revealed that inadequate digital infrastructure, limited access to electricity, and a shortage of skilled workforce are the primary challenges faced by developing countries in the supply chain domain. The study systematically examines industry 4.0 technologies and indicates a 20-30% improvement in supply chain efficiency through the adoption of key technologies like IoT, AI, and blockchain. The study concludes by offering future research on industry 4.0 in supply chain management. The study results are assumed to offer insightful information to supply chain managers in developing countries, by enabling them with a deeper understanding of the major challenges and key drivers involved in integrating Industry 4.0 in their organizations and network.
Abstract Agri-Photovoltaic (APV) systems combine electricity generation and agricultural production on the same land. The physiological impacts of the shading imposed on crops cultivated under such systems are not fully understood. This study evaluated the impact of APV shading on tomato physiology and productivity through two field experiments conducted in 2022 and 2023 at Bar Ilan University, Israel. Processing tomato plants (Heinz 1648, Heinz 4107) were grown in seven north–south oriented rows (T1–T7) situated between two photovoltaic (PV) panel arrays. The arrays consisted of 24 east–west-facing, single axis sun-tracking PV modules installed 1.7 m above the ground. Fruits were harvested 95–98 days after planting. Results demonstrated a strong positive correlation between total photosynthetic irradiance and tomato productivity. Shading imposed by the PV modules reduced chlorophyll content, total biomass, fruit yield, and fruit quality. Plants in the central row T4, receiving highest light availability within the APV system (1.96% less light compared to adjacent open fields), served as a control. Plants grown directly under the PV modules in rows T1 and T7 experienced the strongest shading and recorded the greatest yield losses (42% and 57%, respectively). Plants in rows with moderate shading T2 and T6 had yield losses of 13% and 20%, respectively, while plants in rows receiving near-full sunlight (T3 and T5) exhibited minimal losses (0% and 6%, respectively). Total fruit yield loss across all seven rows was 19.4% compared to conventional cultivation. Reducing the number of rows between PV modules from seven to six or five decreased yield losses to 13.0% and 7.2%, respectively, and improved the land equivalent ratio (LER). The PV systems generated ~ 29,000 kWh/1000 m2 per growing season and ~ 70,000 kWh/1000 m2 during the offseason. Notably, the annual net profit from tomato production under APV was 9.54 times higher than conventional agriculture.
Shixin Zhao, Xingbao Lyu, Aleksandr Astafiev
et al.
Abstract The Gatchina discharge phenomenon holds significant promise as a laboratory model for simulating ball lightning. However, crucial aspects concerning the plasma components of the resulting afterglow remain unresolved. Notably, the measurement of the electron density, a critical parameter, has not been fully achieved thus far. In this study, microwave diagnostics and video recording were employed during a pulsed Gatchina discharge, along with synchronous measurement of discharge current and voltage. Distinct antennas were positioned at different heights to enable separate diagnosis of the discharge and the ensuing long‐lived afterglow. The findings revealed that during the active phase of the Gatchina discharge, the plasma density was substantial enough to cause reflection of an electromagnetic wave with a frequency of 20 GHz from this highly conductive object. In the afterglow, the signal experienced only a moderate weakening of 10–20 percent, facilitating the determination of the time dependence of average electron density during the afterglow's passage between the two antennas. These measurements verified the unusually slow plasma decay in the afterglow of the Gatchina discharge, suggesting the potential significance of chemi‐ionisation processes involving long‐lived (metastable) particles.
Pedro Luis Camuñas García-Miguel, Jaime Alonso-Martinez, Santiago Arnaltes Gómez
et al.
Participation in the electricity market requires making commitments without knowing the real generation or electricity prices. This is problematic for renewable generators due to their fluctuating output. Battery energy storage systems (BESSs) integrated with renewable sources in a hybrid farm (HF) can alleviate imbalances and increase power system flexibility. However, the impact of battery degradation on long-term profitability must be taken into account when choosing the correct market participation strategy. This study evaluates the state-of-the-art on energy management systems (EMS) for HFs participating in day-ahead and intraday markets, incorporating both BESSs’ calendar and cycling degradation. Results suggest that efforts to attain additional profits in intraday markets can be detrimental, especially when the degradation effect is considered in the analysis. A new market participation strategy is proposed that aims to address the limitations of market overlapping and forecasting errors. The results demonstrate that the proposed method can enhance long-term benefits while also reducing battery degradation.
Production of electric energy or power. Powerplants. Central stations, Industrial electrochemistry
Ebbe Kyhl Gøtske, Gorm Bruun Andresen, Marta Victoria
Future highly renewable energy systems might require substantial storage deployment. At the current stage, the technology portfolio of dominant storage options is limited to pumped-hydro storage and Li-ion batteries. It is uncertain which storage design will be able to compete with these options. Considering Europe as a case study, we derive the cost and efficiency requirements of a generic storage technology, which we refer to as storage-X, to be deployed in the cost-optimal system. This is performed while including existing pumped-hydro facilities and accounting for the competition from stationary Li-ion batteries, flexible generation technology, and flexible demand in a highly renewable sector-coupled energy system. Based on a sample space of 724 storage configurations, we show that energy capacity cost and discharge efficiency largely determine the optimal storage deployment, in agreement with previous studies. Here, we show that charge capacity cost is also important due to its impact on renewable curtailment. A significant deployment of storage-X in a cost-optimal system requires (a) discharge efficiency of at least 95%, (b) discharge efficiency of at least 50% together with low energy capacity cost (10 €/kWh), or (c) discharge efficiency of at least 25% with very low energy capacity cost (2 €/kWh). Comparing our findings with seven emerging technologies reveals that none of them fulfill these requirements. Thermal energy storage is, however, on the verge of qualifying due to its low energy capacity cost and concurrent low charge capacity cost. Exploring the space of storage designs reveals that system cost reduction from storage-X deployment can reach 9% at its best, but this requires high round-trip efficiency (RTE≥90%) and low charge capacity cost (35 €/kW).
Production of electric energy or power. Powerplants. Central stations, Renewable energy sources
Due to the breakdown of the test-side fracture during the non-outage voltage-withstand test, the double-fracture disconnect switch (DDS) with a common chamber structure has been exposed to the risk of affecting the insulation performance of the operating-side fracture. Therefore, it is necessary to study the electric field distribution and breakdown characteristics of the DSS during the design phase. In this paper, the newly developed 110 kV three-phase common box type GIS DDS was taken as an example. The finite element method was employed to simulate the electric field, as well as to obtain the internal electric field strength distribution during non-outage voltage-withstand test at the actual site. Based on the electric field calculation results and the breakdown criteria deduced by Thomson discharge theory, the breakdown characteristics of the two fractures were studied during non-outage voltage-withstand test. It was proven that the breakdown of the test-side fracture would not affect the insulation performance of the operating-side in the non-outage voltage-withstand testing process of the DDS. The results provide theoretical support for non-outage expansion and on-site insulation test during the second-phase expansion, and also provide a more detailed theoretical basis for insulation verification in the future development of the next-generation DDS equipment.
Electricity, Production of electric energy or power. Powerplants. Central stations
Kamran Taghizad-Tavana, As’ad Alizadeh, Mohsen Ghanbari-Ghalehjoughi
et al.
Due to the rapid expansion of electric vehicles (EVs), they are expected to be one of the main contributors to transportation. The increasing use of fossil fuels as one of the most available energy sources has led to the emission of greenhouse gases, which will play a vital role in achieving a sustainable transportation system. Developed and developing countries have long-term plans and policies to use EVs instead of internal combustion vehicles and to use renewable energy to generate electricity, which increases the number of charging stations. Recently, to meet the charging demand for EVs, the main focus of researchers has been on smart charging solutions. In addition, maintaining power quality and peak demand for grids has become very difficult due to the widespread deployment of EVs as personal and commercial vehicles. This paper provides information on EV charging control that can be used to improve the design and implementation of charging station infrastructure. An in-depth analysis of EV types, global charging standards, and the architectures of AC-DC and DC-DC converters are covered in this review article. In addition, investigating the role of EV collectors, as well as EV penetration, in electric energy systems to facilitate the integration of electric energy systems with renewable energy sources is one of the main goals of this paper.