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Building-Integrated Photovoltaic/Thermal (BIPVT) technology offers multiple advantages; however, these types of installations include materials such as Photovoltaic (PV) cells and metals which considerably influence BIPVT environmental impact. Therefore, there is a need to evaluate BIPVT environmental profile, for instance by means of Life Cycle Assessment (LCA). In light of the issues mentioned above, the present article is an LCA study that assesses the environmental performance of a BIPVT prototype that has been developed and patented at the Ulster University (Belfast, UK). The investigation places emphasis on material manufacturing, based on Cumulative Energy Demand (CED), Global Warming Potential (GWP), ReCiPe, Ecological footprint and USEtox. The results show that according to all the adopted methods/environmental indicators and based on primary materials, the PV cells and the two vessels (steel) are the components with the three highest impacts. Scenarios which include recycling of steel, plastics and brass (landfill for the other materials has been assumed), based on CED, GWP 100a and ReCiPe endpoint, have been examined. It was found that steel recycling offers a considerable impact reduction, ranging from 47% to 85%. Furthermore, the impact of the proposed BIPVT module per m2 of thermal absorber has been calculated. The results, based on primary materials, show 4.92 GJprim/m2 and 0.34 t CO2.eq/m2 (GWP 100a). In addition, according to USEtox/ecotoxicity, USEtox/human toxicity-non-cancer (scenario based on primary materials), the PV cells present the highest contributions to the total impact of the module: 55% in terms of ecotoxicity and 86% concerning human toxicity/non-cancer. A comparison with literature is provided. Moreover, a separate section of the article is about factors which influence BIPVT environmental profile, discussing parameters such as the storage materials and the end-of-life management.

The neutron time-of-flight facility n_TOF features a white neutron source produced by spallation through 20GeV/c protons impinging on a lead target. The facility, aiming primarily at the measurement of neutron-induced reaction cross sections, was operating at CERN between 2001 and 2004, and then underwent a major upgrade in 2008. This paper presents in detail all the characteristics of the new neutron beam in the currently available configurations, which correspond to two different collimation systems and two choices of neutron moderator. The characteristics discussed include the intensity and energy dependence of the neutron flux, the spatial profile of the beam, the in-beam background components and the energy resolution/broadening. The discussion of these features is based on dedicated measurements and Monte Carlo simulations, and includes estimations of the systematic uncertainties of the mentioned quantities.

Spurious regression analysis in panel data when the time series are cross section dependent is analysed in the article. We show that consistent estimation of the long‐run average parameter is possible once we control for cross section dependence using cross section averages in the spirit of the common correlated effects approach proposed by Pesaran. This result is used to design a panel cointegration test statistic accounting for cross section dependence. The performance of the proposal is investigated in comparison with factor‐based methods to control for cross section dependence when strong, semi‐weak and weak cross section dependence may be present.

In this paper, an algorithm for energy management system (EMS) based on multi-layer ant colony optimization (EMS-MACO) is presented to find energy scheduling in Microgrid (MG). The aim of study is to figure out the optimum operation of micro-sources for decreasing the electricity production cost by hourly day-ahead and real time scheduling. The proposed algorithm is based on ant colony optimization (ACO) method and is able to analyze the technical and economic time dependent constraints. This algorithm attempts to meet the required load demand with minimum energy cost in a local energy market (LEM) structure. Performance of MACO is compared with modified conventional EMS (MCEMS) and particle swarm optimization (PSO) based EMS. Analysis of obtained results demonstrates that the system performance is improved also the energy cost is reduced about 20% and 5% by applying MACO in comparison with MCEMS and PSO, respectively. Furthermore, the plug and play capability in real time applications is investigated by using different scenarios and the system adequate performance is validated experimentally too. (C) 2015 Elsevier Ltd. All rights reserved.

© 2018 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works. Resonance instabilities in power systems can be assessed with the positive-net-damping stability criterion. This criterion is a review of the complex torque coefficients method, but it does not provide the frequency of the closed-loop oscillatory modes. This paper presents an alternative approach of the positive-net-damping stability criterion to analyze electrical resonance instability. In this approach, resonance instabilities are identified in feedback systems derived from impedance-based equivalent circuits. The proposed approach is used to characterize the frequency of closed-loop oscillatory modes and identify the physical and control parameters of the system that increase or reduce the damping of these modes. The extension of the proposed approach to study the stability of single-input single-output and multiple-input multiple-output feedback systems is analyzed, and the approach is also compared with other stability methods in the literature. An example of an offshore wind power plant illustrates the theoretical study and compares the proposed approach with different methods to evaluate stability. Time-domain simulations in Power System Computer Aided Design/Electro Magnetic Transient Design and Control (PSCAD/EMTDC) are shown to validate the stability study.