scholarly journals Novel Grounding Electrode Model with Axial Construction Space Consideration

Energies ◽  
2019 ◽  
Vol 12 (24) ◽  
pp. 4765
Author(s):  
Yihua Dan ◽  
Zhanlong Zhang ◽  
Yiqiao Li ◽  
Jun Deng ◽  
Jing Zou
Keyword(s):  
Structural Parameters ◽  
Electrical Potential ◽  
Calculation Model ◽  
Maintenance Cost ◽  
Grounding Resistance ◽  
Additional Resistance ◽  
Grounding Electrode ◽  
Touch Voltage ◽  
Operation And Maintenance Cost ◽  
Electrical Apparatus

Grounding electrodes are used to ensure safe operation of electrical apparatus. The limited axial construction space for grounding electrodes is a significant constraining factor. Grounding performance will attenuate rapidly under the influence of the reduced length of horizontal or vertical grounding electrodes. However, if additional resistance-reducing measures are adopted, the operation and maintenance cost of grounding electrodes will considerably increase. To solve above problem, this study proposed a novel grounding model that uses a helical grounding electrode to improve grounding performance within limited axial construction space. Firstly, a calculation model of finite element methods (FEM) is built based on the concept of increasing the contact area between the grounding electrodes and the soil. Grounding performance parameters of helical grounding electrodes, grounding resistance, electrical potential rise (EPR) distribution and maximum touch voltage, are analyzed. At the same time, structural parameters and buried depth for the helical grounding electrodes are studied and the optimal design criteria for the parameters are given. Results show that the helical grounding electrode exhibits better grounding performance in a limited axial construction area.

scholarly journals Analysis and Optimization of a Novel Hexagonal Waveguide Concentrator for Solar Thermal Applications

Energies ◽  
2021 ◽  
Vol 14 (8) ◽  
pp. 2146
Author(s):  
Karunesh Kant ◽  
Karthik Nithyanandam ◽  
Ranga Pitchumani
Keyword(s):  
Industrial Process ◽  
Cost Effective ◽  
Solar Irradiation ◽  
Maintenance Cost ◽  
Solar Concentrator ◽  
Thermal Desalination ◽  
Process Heat ◽  
Solar Thermal Applications ◽  
The Cost ◽  
Operation And Maintenance Cost

This paper analyzes a novel, cost-effective planar waveguide solar concentrator design that is inspired by cellular hexagonal structures in nature with the benefits of facile installation and low operation and maintenance cost. A coupled thermal and optical analysis of solar irradiation through an ideal hexagonal waveguide concentrator integrated with a linear receiver is presented, along with a cost analysis methodology, to establish the upper limit of performance. The techno-economic model, coupled with numerical optimization, is used to determine designs that maximized power density and minimized the cost of heat in the temperature range of 100–250 °C, which constitutes more than half of the industrial process heat demand. Depending on the incident solar irradiation and the application temperature, the cost of heat for the optimal design configuration ranged between 0.1–0.27 $/W and 0.075–0.18 $/W for waveguide made of ZK7 glass and polycarbonate, respectively. A techno-economic analysis showed the potential of the technology to achieve cost as low as 80 $/m2 and 61 $/m2 for waveguide made of ZK7 glass and polycarbonate material, respectively, which is less than half the cost of state-of-the-art parabolic trough concentrators. Overall, the hexagonal waveguide solar concentrator technology shows immense potential for decarbonizing the industrial process heat and thermal desalination sectors.

scholarly journals Analysis on structural parameters and electrical performance of dc deep well grounding electrode

2019 ◽  
Vol 2019 (16) ◽  
pp. 2366-2370 ◽  
Author(s):  
Yun Teng ◽  
Xishan Wen ◽  
Hansheng Cai ◽  
Lei Jia ◽  
Gang Liu ◽  
...  
Keyword(s):  
Structural Parameters ◽  
Electrical Performance ◽  
Deep Well ◽  
Grounding Electrode

scholarly journals Techno-Economic Feasibility Study of Investigation of Renewable Energy System for Rural Electrification in South Algeria

2018 ◽  
Vol 8 (5) ◽  
pp. 3421-3426 ◽  
Author(s):  
F. Chermat ◽  
M. Khemliche ◽  
A. E. Badoud ◽  
S. Latreche
Keyword(s):  
Greenhouse Gas Emission ◽  
Electrical Energy ◽  
Energy System ◽  
Economic Feasibility ◽  
Maintenance Cost ◽  
Management Algorithm ◽  
Cost Of Energy ◽  
The Cost ◽  
Operation And Maintenance Cost ◽  
Different Sources

This work aims to consider the combination of different technologies regarding energy production and management with four possible configurations. We present an energy management algorithm to detect the best design and the best configuration from the combination of different sources. This combination allows us to produce the necessary electrical energy for supplying habitation without interruption. A comparative study is conducted among the different combinations on the basis of the cost of energy, diesel consumption, diesel price, capital cost, replacement cost, operation, and maintenance cost and greenhouse gas emission. Sensitivity analysis is also performed.

A Mathematical Calculation Method for Hysteresis Characteristics Analysis of Arc-Shaped Finger Seal

2020 ◽  
Author(s):  
Chun-Hua Du ◽  
Yan-Chao Zhang ◽  
Ya-Hui Cui ◽  
Shu-Na Dong ◽  
Hong-Hu Ji ◽  
...  
Keyword(s):  
Mathematical Model ◽  
Structural Parameters ◽  
Maximum Error ◽  
Calculation Model ◽  
Correction Coefficient ◽  
Research Results ◽  
Characteristics Analysis ◽  
Leakage Characteristics ◽  
The Mathematical Model ◽  
Hysteresis Characteristics

Abstract In order to accurately predict the hysteresis characteristics of finger seal, the minimum hysteresis which can directly reflect the hysteresis of finger seal is proposed to characterize the hysteresis of finger seal. The mathematical model for calculating the minimum hysteresis of finger seal is established, the correction coefficient in the mathematical model is determined, and the mathematical model is verified by experiments. The influence of the structure and working condition parameters of finger laminates on the hysteresis characteristics is studied based on the modified calculation model, and the rule of influence is obtained in the end. Research results show that the maximum error between the leakage characteristics numerical calculation of finger seal base on modified calculation model and the experiment results is 7.64%, and the mathematical model of the minimum hysteresis is reasonable and reliable. The descending order of influence degree of structural parameters on the hysteresis characteristics of finger seal is: thickness of each finger laminate, finger repeat angle, arc radius of the finger beam arcs‘ centers, diameter of the finger base circle, width of the interstice between fingers, arc radius of finger beam. The research results provide a theoretical basis for further research on the influence of hysteresis on the finger seal leakage characteristics and the optimal design of finger seal structure.

scholarly journals Grounding System Cost Analysis Using Optimization Algorithms

Energies ◽  
2018 ◽  
Vol 11 (12) ◽  
pp. 3484 ◽  
Author(s):  
Jau-Woei Perng ◽  
Yi-Chang Kuo ◽  
Shih-Pin Lu
Keyword(s):  
Human Body ◽  
Rbf Neural Network ◽  
Grounding System ◽  
Grounding Resistance ◽  
Grounding Grid ◽  
Engineering Costs ◽  
System Data ◽  
And Performance ◽  
Touch Voltage ◽  
Resistance Value

In this study, the concept of grounding systems is related to the voltage tolerance of the human body (human body voltage tolerance safety value). The maximum touch voltage target and grounding resistance values are calculated in order to compute the grounding resistance on the basis of system data. Typically, the grounding resistance value is inversely proportional to the laying depth of the grounding grid and the number of grounded copper rods. In other words, to improve the performance of the grounding system, either the layering depth of the grounding grid or the number of grounded copper rods should be increased, or both of them should be simultaneously increased. Better grounding resistance values result in increased engineering costs. There are numerous solutions for the grounding target value. Grounding systems are designed to find the combination of the layering depth of the grounding grid and the number of grounded copper rods by considering both cost and performance. In this study, we used a fuzzy algorithm on the genetic algorithm (GA), multi-objective particle swarm optimization (MOPSO) algorithm, Bees, IEEE Std. 80-2000, and Schwarz’s equation based on a power company’s substation grounding system data to optimize the grounding resistance performance and reduce system costs. The MOPSO algorithm returned optimal results. The radial basis function (RBF) neural network curve is obtained by the MOPSO algorithm with three variables (i.e., number of grounded copper rods, grounding resistance value, and grounding grid laying depth), and the simulation results of the electrical transient analysis program (ETAP) system are verified. This could be a future reference for substation designers and architects.

scholarly journals Analysis of Contracts to Build Energy Infrastructures to Optimize the OPEX

2020 ◽  
Vol 12 (17) ◽  
pp. 7232
Author(s):  
Jesus Javier Losada-Maseda ◽  
Laura Castro-Santos ◽  
Manuel Ángel Graña-López ◽  
Ana Isabel García-Diez ◽  
Almudena Filgueira-Vizoso
Keyword(s):  
Energy Sector ◽  
Maintenance Cost ◽  
Maintenance Costs ◽  
Execution Costs ◽  
Operation And Maintenance ◽  
Maximum Profit ◽  
Hydroelectric Plants ◽  
Operation And Maintenance Cost ◽  
Contractual Agreement ◽  
Energy Infrastructures

The employer (owner) of the project wants to obtain the maximum profit for the money invested and the consultant (contractor) will try to give less for that money. The regulation of their relationship is based on the contractual agreement, which in the energy sector is mainly based on the engineering, procurement, and construction (EPC) model. The objective of this work was to evaluate which factors should be included in the drafting of contracts, to minimize problems between the parties, and thus minimize execution costs and optimize operation and maintenance costs. Information and data on the integration of operability and maintainability criteria in contracts for 158 projects, with a total contract value of close to €40,000M, were analyzed. Several of those projects corresponded to wind, solar, and hydroelectric plants. The information collected the perception of the agents involved, and was classified according to the experience of the agents consulted in the operation and maintenance areas. Finally, the proposed criteria were prioritized. In general, the owner is willing to introduce these criteria in his contracts if they reduce the operation and maintenance cost by around 1–5%, while the contractor is interested in increasing his probability to be selected by 1–3%.

scholarly journals Economic Assessment of Distributed Generation Technologies: A Feasibility Study and Comparison with the Literature

Energies ◽  
2020 ◽  
Vol 13 (11) ◽  
pp. 2764
Author(s):  
Ameena Saad Al-Sumaiti ◽  
Abdollah Kavousi-Fard ◽  
Magdy Salama ◽  
Motahareh Pourbehzadi ◽  
Srikanth Reddy ◽  
...  
Keyword(s):  
Power Generation ◽  
Sensitivity Analysis ◽  
Wind Energy ◽  
Distributed Generation ◽  
Economic Assessment ◽  
Rate Of Return ◽  
Maintenance Cost ◽  
Fuel Cost ◽  
Operation And Maintenance ◽  
Operation And Maintenance Cost

With the negative climate impact of fossil fuel power generation and the requirement of global policy to shift towards a green mix of energy production, the investment in renewable energy is an opportunity in developing countries. However, poor economy associated with limited income, funds availability, and regulations governing project funding and development are key factors that challenge investors in the energy sector. Given the various power generation resources, including renewables, it is necessary to evaluate the possible power generation investment options from an economic perspective. To realize this objective, solar PV, wind and diesel power generations are economically compared, considering the incremental rate of return and incremental benefit to cost ratio techniques. The alternative investment options of distributed generation technologies are evaluated for Maharashtra, India under different depreciation methods, and the effect of the latter on selecting the best investment candidate is investigated. The paper also conducts sensitivity analysis to examine the impact of capital cost, operation and maintenance cost, and fuel cost variations on the selection decision considering a comparison of the different general projects’ cash flow structures discussed in the literature. The economic aspects of selecting a project among possible alternatives for an investment in the power sector are analyzed, and the presented review provides comprehensive comparisons with respect to the literature approaches. The results reveal that, in the benchmark case study, the PV project is rejected and disregarded from further comparisons with other candidate projects since its equity internal rate of return (10.25%) is less than the minimum accepted rate of return, leaving the selection between wind and diesel energy projects. The study reveals that the incremental rates of return under such a comparison are 37.88%, 45.94% and 37.50% when MACRS, declining balance and straight line depreciations techniques are applied, respectively. Thus, the wind energy project is the favored option in this case. For the economic assessment of other case studies, the application of both sensitivity analysis on the capital cost and operation and maintenance cost and literature approaches to structure the projects reveal that wind energy for Maharashtra, India is a more attractive and feasible option compared to other distribution generation projects, while diesel is only considered to be a good option when its fuel cost is reduced by 5%. Finally, the paper highlights policy implications that can influence the decision to move towards investment in distributed generation technologies as a future research direction.

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