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• Optimised off-grid electricity supply of households in Cambodia and Norway. • In Norway (low irradiation) TEG (€8/W) is part of the optimal hybrid system. • Even considering double cost (€16/W) TEG is part of the optimal system in Norway. • In Cambodia (high irradiation) TEG prices should be reduced 25% (to €6/W). This paper shows, for the first time, the optimisation of the electrical supply in off-grid systems by means of hybrid renewable systems (photovoltaic + wind + battery + fossil fuel) including thermoelectric generator (which source of heat is the exhaust gas of a stove used for cooking or heating). The objective is to minimise the net present cost. An advanced battery model and the accurate calculation of the net present cost (including all the costs during the system lifetime) are considered in the optimisation of this kind of systems. The standard simplified model of the thermoelectric generator is used, as more complex models cannot be used in an optimisation framework, where hundreds or thousands of different cases must be simulated (each combination of components must be simulated at least during one year, in 1-min steps). The optimization is carried out efficiently by means of genetic algorithms. The method has been applied in the optimisation of two cases of low consumption off-grid households (Cambodia and Norway). Thermoelectric generator (costing €8/W) is part of the optimal solution in the case of Norway. In Cambodia, to be part of the optimal system, acquisition cost of the thermoelectric generator should be reduced by 25%. [ABSTRACT FROM AUTHOR]

The Divertor Tokamak Test (DTT) facility will be the link between ITER and DEMO as regards the study of the power exhaust in the divertor structure. In order to accomplish this goal, the Italian DTT will be a complete superconducting tokamak with 45 MW of additional power coupled to the plasma. According to the last requirements, the DTT coil power supplies are designed to achieve a toroidal field of 6 T and a 5.5 MA plasma in single-null configuration, but also to achieve double-null (with plasma at 5.5 MA), snow-flake (4.5 MA), super-X (3 MA) and other advanced configurations. This paper presents the conceptual design of the DTT power supply and electrical systems, including the site layout, the distribution networks, the expected scenarios and the mechanisms for breakdown and emergency discharge. In particular, the main rationales for the selection of the power supply topology are summarized. The power demand from the grid, presented in the various design options, can reach values above 300 MVA, including the contribution of the additional heating and current drive systems and of the auxiliary services. [ABSTRACT FROM AUTHOR]

• We describe the design of the MB and PF joints in ITER. • The joints preparation for hydraulic characterization is detailed. • The hydraulic test sequence is explained. • The main results are highlighted. • The consequences on the cryoplant operation are raised. The ITER magnet system will be the largest superconducting magnet system ever built. The system, all inside a cryostat, is mainly composed of a Central Solenoid (CS) split in 6 modules, a set of 18 Toroidal Field (TF) d -shaped coils and 6 Poloidal Field (PF) coils. Each of these coils uses variable type of cable-in-conduit-conductors (CICC) actively cooled by a forced supercritical helium flow. Their electrical supply from the current feedthrough of the cryostat is done with Main Busbars (MB) using similar CICC. The electrical MB to coils as well as internal PF and TF coils connections rely on the twin box concept developed by CEA in the early R&D phase. After electrical validation of joint prototypes for the PF and the MB conductors on full size samples, specific hydraulic characterization tasks were done through the Magnet Infrastructure Facilities for ITER (MIFI) contract between ITER Organization (IO) and CEA devoted to develop, improve and qualify manufactured components and assembly processes. These tasks were done on the samples using the CEA OTHELLO dedicated facility able to operate with gaseous N 2 in a large Reynolds range at room temperature. The paper explains the way followed to get a full hydraulic characterization of the MB and PF5 joints for the two flow directions. The study of the flow distribution between parallel cooling channels inside the PF5 joint revealed a bypass of the active joint region. The paper reports on this hydraulic behaviour in the relevant magnets operating conditions and outlines the design changes in the joints provoked by the results of this study. [ABSTRACT FROM AUTHOR]

Copyright of Electrical Engineering & Electromechanics is the property of National Technical University, Kharkiv Polytechnic Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A framework is planned to supply electrical and thermal loads by joint application of a hydrogen storage system (HSS) and a fuel cell. The system, including electrical and thermal loads, is connected to the upstream network. The bidirectional operation is defined for the system, and the system can buy energy from the grid or sell energy to the grid. A water electrolyzer is applied to produce hydrogen from water and store electricity in the form of hydrogen. The stored hydrogen supplies the thermal loads, as well as the fuel cell. The electrical loads are directly connected to the grid and are supplied by the grid. The electricity is received from the fuel cell at hours 17 to 22. When the price of electricity is high, the electrical loads can receive their power from the fuel cell rather than the grid. Additionally, any excess electricity may be sold to the grid. The uncertainty in the thermal and electrical loads is modeled and formulated as stochastic programming. The hydrogen is fed to the fuel cell and the thermal loads. The proposed model minimizes the daily operational cost of the system. The results demonstrate that the daily operational cost of the system is $22.274 USD/day. The bidirectional operation reduces the daily operational cost by about 79%. The unceratinty increases the cost by about 15%. [ABSTRACT FROM AUTHOR]

In an electrical distribution network, Logic Selectivity significantly reduces both the number and duration of outages. Generic Object-Oriented Substation Events (GOOSE) have a key role in the decision-making process of substation protection devices using GOOSE-based Logic Selectivity. GOOSE messages are exchanged between remote protection devices over the communication network. Secured communication with low latency and high reliability is therefore required in order to ensure reliable operation as well as meeting real-time requirement of the Logic Selectivity application. There is thus a need to evaluate feasibility of the selected communication network technology for Logic Selectivity use cases. This paper analyzes reliability of cellular 4G/LTE Internet for GOOSE communication in a Logic Selectivity application. For this purpose, experimental lab set-ups are introduced for different configurations: ordinary GOOSE communication, secured GOOSE communication by IPsec in Transport mode, and redundant GOOSE communication using the IEC 62439-3 Parallel Redundancy Protocol. In each configuration, the GOOSE retransmissions are recorded for a period of three days and the average GOOSE transmission time is measured. Furthermore, the measured data is classified into histograms and a probability value for communication reliability, based on the transmission time, is calculated. The statistical analysis shows that 4G Internet satisfies the real-time and reliability requirements for secure and highly available GOOSE-based Logic Selectivity. [ABSTRACT FROM AUTHOR]

Linearized models of power systems are often desirable to formulate tractable control and optimization problems that still reflect real-world physics adequately under various operating conditions. In this paper, we propose an approach that can make use of known data concerning the distribution of demand, and/or intermittent supply, to minimize expected model inconsistency with respect to the original non-linear model. The optimal linearization is obtained by approximating a generalized moment problem with a hierarchy of sparse semi-definite relaxations. The output is a linearization point that minimizes the expected absolute constraint violation with respect to the uncertain supply and demand, under optimal power flow solutions. Numerical results for different power systems demonstrate the accuracy and scalability of our linearization method. [ABSTRACT FROM AUTHOR]

The industrial segment of the electrical industry has carved out some time-tested methods of distribution. But the flood of new products and the intensified price competition in many lines is threatening established marketing channels. The author discusses the challenge to the middlemen engaged in the distribution of these products. [ABSTRACT FROM AUTHOR]

The elaboration discusses selected aspects of parking supply of aircraft with electricity generated by mobile, airfield sources. In terms of sublime electrical and electronic systems, as well as avionic systems installed on-board of contemporary aircraft, the quality of electricity supplied by ground sources results in their manufacturers facing with high requirements that are contained in relevant standards and regulations. The quality of electricity generated by ground sources and their compatibility have a direct impact, among others, on the calibration of aircraft avionics systems during the ground flight preparation, which directly contributes to the safety of air operations. Therefore, the possibility of constant real-time monitoring of the supplied electricity (specific parameters) enabling immediate identification, recording, adjusting the deviations, hence, preventing damage or improper preparation of an aircraft for flight, becomes a non-trivial issue. [ABSTRACT FROM AUTHOR]

Abstract: Electrical supply sources based on photovoltaic converters and tritium radioluminescent lamps with blue and green glow are developed and fabricated. AlxGa1 -xAs/n-GaAs p-n heterostructures with various band-gap widths (Eg = 1.4-1.9 eV) and compositions of the active region (x = 0.1-0.35) are prepared by low-temperature liquid-phase epitaxy. The photovoltaic converter with an area of S = 0.12 cm2 upon irradiation by a green tritium lamp (wavelength λ = 550 nm) has the short-circuit current density 180 nA/cm2 and output electrical power >100 nW/cm2. [ABSTRACT FROM AUTHOR]

Abstract The human interaction with the building is a key cause of uncertainty when predicting energy consumption of buildings. Building occupants affect building energy use directly and indirectly by interacting with building energy systems, for example, by adjusting thermostats, switching lights on/off, using electrical devices and opening/closing windows. The occupants' daily activity profiles and occupancy patterns clearly shape the timing and magnitude of energy demand in households. Modelling energy-related human activities throughout the day, therefore, is a crucial task for prediction of energy use and, consequently, to reduce the gap between real and predicted building energy use. This study modelled data gathered in the diary-based Danish Time Use Survey (TUS) 2008/09 of 9640 individuals from 4679 households. Individuals' daily activities were logged in 10-min time increments for 24 h, starting and ending at 04:00, during both weekdays and weekends. The aims of this study were to (i) profile energy-related daily activities of occupants during different seasons and weekdays/weekends (ii) investigate time-related characteristics of activities such as starting and ending times and durations, and (iii) profile occupancy patterns for weekdays/weekends for different household types. The outcomes provide valuable input for building energy simulation for bridging the gap between simulated and real energy consumption in the Danish residential sector; typical occupancy profiles for different household types for different days of the week are freely available online [1]. [ABSTRACT FROM AUTHOR]

• Minimize the total annualized net present cost and levelized cost of energy in an entirely hybrid renewable energy system. • Offering modified economic modeling for the system's elements. • Presenting adaptive smart charging strategies for Electric Vehicles (EVs) in a stand-alone hybrid system. • Considering the uncertainties in the electrical loads, thermal loads, renewable energy resources, and EVs' parameters. • Utilizing a modified combination of GWO-SCA to obtain a reliable optimal solution with a low standard deviation. Renewable energy resources have gotten considerable attention in recent years owing to significant advancements in power electronics technologies, decreased cost of utilizing renewable resources, and increasing concerns about environmental pollutants, particularly in stand-alone applications. Utilizing entirely renewable resources to meet demand has numerous advantages, including lower energy prices, energy price stability, local accessibility, etc. The capability to apply a modified combination of the gray wolf optimization algorithm and the sine–cosine algorithm is evaluated to minimize the levelized cost of energy and the total annualized net present cost (comprising investment, replacement, decommissioning, and operation & maintenance costs) of the proposed system while complying with system constraints and demand requirements. The optimal power planning of a stand-alone hybrid entirely renewable system comprising wind turbines, PV systems, bio-waste units, and storage devices to supply electrical and thermal loads simultaneously was investigated in this paper. A parking lot for electric vehicles is also considered in non-smart and smart charging strategies. In addition, a redefined scenario-based stochastic optimization is utilized to consider uncertainties in electrical and thermal loads, EVs' parameters, and renewable energy resources. The proposed approach is implemented on a small system in Espoo, Finland. The results confirm its efficiency for economically and uninterrupted supplying electrical and thermal demands simultaneously in a stand-alone hybrid system with entirely renewable resources. [ABSTRACT FROM AUTHOR]

Copyright of DYNA - Ingeniería e Industria is the property of Publicaciones Dyna SL and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The paper presents an analysis of the guidelines for the rehabilitation of irrigation plots to sprinkler watering. Irrigation systems from Romania were conducted in 40 to 50 years, and most are degraded at the present stage. Part of irrigation sprinkler plots is in operation, but the important phenomena of wear and aging. Their rehabilitation is carried out on the two major components, pressure pumping station and (PSP) and the network of pipelines. Rehabilitation and modernisation of the PSP is achieved differentiated on structural and functional components: constructive structure, technological hydromechanics line, protection installation from accidental pressure variation, electrical supply installation, installation of monitoring and automation parameters. Case studies drawn on several SPP from Moldova reveal the complexities of rehabilitation and modernization. This should be the successive stages and by using modern materials and technology execution. [ABSTRACT FROM AUTHOR]

This paper reports the investigation outcomes of the recent Super Typhoon Haiyan (also known as Hurricane Yolanda) in the Philippines using a basic structure damage rating technique. The rating technique ranked damaged conditions based on a 0 to 3 rating. A total of 156 structures were analyzed using the rating technique. Unlike previously published condition ratings, the technique does not include functional assessments such as mechanical and electrical systems and does not directly consider habitant safety nor costs to structure. The intent of the rating is to provide a quantitative measure of the effects of Haiyan. The outcomes indicate that wind damage dominated as the major cause of failures (53%) and that roof damage is the most significant of the damage modes (21%). The rating gives a first-order assessment of the damaged conditions of the structures pertaining to the loading effects (wind, water or storm surge, or combined) from Super Typhoon Haiyan. [ABSTRACT FROM AUTHOR]

Published UK 2050 energy scenarios specify a range of decarbonised supply side technologies combined with electrification of transportation and heating. These scenarios are designed to meet CO 2 reduction targets whilst maintaining reliability of supply. Current models of the UK energy system either make significant assumptions about the role of demand side management or do not carry out the analysis at sufficient resolution and hence determining the impact of heat electrification on the reliability of supply of the scenarios is not possible. This paper presents a new model that estimates national supply and demand, hour-by-hour. Calculations are based on 11 years of weather data which allows a probabilistic assessment of deficit frequency throughout the day. It is found that achieving demand reduction targets are far more important than meeting electrification targets and that significant adoption of CHP is most likely to deliver a viable energy future for the UK. [ABSTRACT FROM AUTHOR]