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Some Concerns Related to the Idea of Energetic Complementarity and Its Application  [PDF]
Flávio P. Livi, Elton G. Rossini, Alexandre Beluco
Energy and Power Engineering (EPE) , 2017, DOI: 10.4236/epe.2017.99032
Abstract: This letter to the editor presents some notes on energetic complementarity and a growing understanding of its role as a planning tool. This letter looks at the fact that an increasing number of works in recent years on this subject has promoted an increase in its level of importance in the design and operation of energy systems. The main change is the consideration of complementarity no longer as a consequence but as a design parameter. The continental dimension of Brazil, for example, should make it obvious that complementarities should be sought among the various energy resources available.
Editorial Special Issue on “Energetic Complementarity”  [PDF]
Alexandre Beluco
Energy and Power Engineering (EPE) , 2017, DOI: 10.4236/epe.2017.99033
Abstract: This editorial presents the motivations that were the focus of the papers that make up this Special Issue on energetic complementarity. The articles deal with the application of the concept of energetic complementarity in time under certain conditions and with the proposition of new means to evaluate complementarity in time between more than two renewable energy resources. An article further proposes a method for establishing energetic complementarity in space, a concept that is important and necessary for management and planning of energy resources but does not yet have tools that allow it to be quantified and handled appropriately. In addition, two letters to the editor discuss issues that still need to be matured for a better understanding and application of the concept of energetic complementarity, both in time and space.
Influence of Time Complementarity on Energy Storage through Batteries in Hydro PV Hybrid Energy System  [PDF]
Frederico A. During Fo, Alexandre Beluco, Elton G. Rossini, José de Souza
Computational Water, Energy, and Environmental Engineering (CWEEE) , 2018, DOI: 10.4236/cweee.2018.73010
Abstract: The notion of energetic complementarity can be a tool for energy resource managers to prioritize energy generation projects based on renewable resources in both interconnected and independent systems. As a tool in decision-making, it is important to know better the influence of energetic complementarity on the performance of hybrid systems especially with regard to energy shortages but also in relation to other parameters. In recent years, hydro PV hybrid systems have become a growing target of researchers and designers for the idea of installing photovoltaic modules on the water surface of reservoirs. Energetic complementarity has three components: time-complementarity, energy-amplitude and amplitude-complementarity. This paper is dedicated to the study of the influence of time-complementarity on the storage of energy through batteries in hydro PV hybrid systems. The method applied is in the literature and suggests the simulation of the system under study with the idealization of energy availabilities, to remove the effects of climatic variations and the characteristic intermittency of renewable resources. Simulations were performed with the well-known software Homer. The results provided the variations of the states of charge of the batteries as a function of different time-complementarities, indicating as expected better performances associated to higher time-complementarities. The results indicated that the cost of energy for a hybrid system with 28 batteries was equal to US$ 0.502 per kWh and that this cost increased as the time complementarity between energy resources moved away from the situation corresponding to full complementarity. The simulations also showed that the maintenance of the zero failure condition supplying the demands of the consumer loads requires that the load be reduced to 52% if the complementarity is reduced from the full complementarity to zero complementarity, with the cost of energy going from US$ 0.502 per kWh to US$ 0.796 per kWh. The results also allow a better understanding of the influence of time complementarity on the performance of hybrid systems.
An Index Assessing the Energetic Complementarity in Time between More than Two Energy Resources  [PDF]
Elizando M. Borba, Renato M. Brito
Energy and Power Engineering (EPE) , 2017, DOI: 10.4236/epe.2017.99035
Abstract: Energy complementarity can be a tool for managers to prioritize investments in new power generation ventures. An index for complementarity assessment should allow comparison of complementarities at different sites. This article proposes a new method for the calculation of complementarity index, allowing the comparison two energy resources and also allowing the comparison of more than two energy resources. In addition, the proposed index still allows the use of hourly or daily series and not only maximum or minimum values. Finally, this article also presents a map for the state of Rio Grande do Sul, the southernmost state of Brazil, indicating the energetic complementarity in time between hydropower, wind energy and PV solar energy.
Some Remarks on the Seismic Demand Estimation in the Context of Vulnerability Assessment of Large Steel Storage Tank Facilities  [PDF]
Antonio Di Carluccio,Giovanni Fabbrocino
ISRN Civil Engineering , 2012, DOI: 10.5402/2012/271414
Abstract: The seismic behavior of steel tanks is relevant in industrial risk assessment because collapse of these structures may trigger other catastrophic phenomena due to loss of containment. Therefore, seismic assessment should be focused on for leakage-based limit states. From a seismic structural perspective, damages suffered by tanks are generally related to large axial compressive stresses, which can induce shell buckling near the base and large displacements of unanchored structures resulting in the detachment of piping. This paper approaches the analysis of seismic response of sliding, nonuplifting, unanchored tanks subject to seismic actions. Simplified methods for dynamic analysis and seismic demand estimation in terms of base displacement and compressive shell stress are analyzed. In particular, attention is focussed on some computational issues related to the solution of the dynamic problem and on the extension of the incremental dynamic analysis (IDA) technique to storage tanks. 1. Introduction Earthquakes represent an external hazard for industrial installations and may trigger accidents, that is, fire and explosions resulting in injury to people and to near field equipments or constructions, whenever structural failures result in the release of hazardous material. In recent years the quantitative risk analysis (QRA) procedures have been extended to include seismic analysis for industrial installation, for example, petrochemical plants, and chemical plants, storage facility [1–3]. From the structural perspective, steel tanks for oil storage are standardized structures both in terms of design and construction [4–6]. A review of the international standards points out that the design procedures evolved slowly. Nevertheless, a large number of postearthquake damage observations [7] are available and empirical vulnerability functions have been developed [8]. This is a privileged case with respect to other civil engineering structures that basically can be seen as single prototypes; however, empirical fragility typically suffers some shortcomings. In fact, site effects can influence vulnerability data, so that a disaggregation is hard to perform. Therefore, the development of analytical models able to predict the response of the structural components and systems under seismic loading is worth exploring. The present work is aimed at discussing a numerical procedure able to analyze the response of anchored and unanchored tanks under two-dimensional ground motion accounting for the structure sliding. The main objective of the study is, in particular, the
Bases for a Methodology Assessing Time Complementarity in Space  [PDF]
Alfonso Risso, Alexandre Beluco
Energy and Power Engineering (EPE) , 2017, DOI: 10.4236/epe.2017.99037
Abstract: Energetic complementarity has been studied in recent years and can be an important tool for managers to decide on the design and operation of hybrid systems based on renewable energy resources. Complementarity is an ability presented by two or more energy resources to complement each other over time. Complementarity can be verified in one place or at different places. This second case can be termed as spatial complementarity and is more complex than the complementarity in the same place, requiring a specific approach for its quantification This paper discusses concepts related to energetic complementarity and presents the basis for a method to evaluate energetic time-complementarity across space, applying the concepts presented to the northern coast of the state of Rio Grande do Sul, the southernmost state of Brazil.
Energetic Macroscopic Representation of an Electrically Heated Building with Electric Thermal Storage and Heating Control for Peak Shaving  [PDF]
Cristina Guzman, Kodjo Agbossou, Alben Cardenas
Energy and Power Engineering (EPE) , 2015, DOI: 10.4236/epe.2015.74014
Abstract: As a part of the Smart Grid concept, an efficient energy management at the residential level has received increasing attention in lately research. Its main focus is to balance the energy consumption in the residential environment in order to avoid the undesirable peaks faced by the electricity supplier. This challenge can be achieved by means of a home energy management system (HEMS). The HEMS may consider local renewable energy production and energy storage, as well as local control of some particular loads when peaks mitigation is necessary. This paper presents the modeling and comparison of two residential systems; one using conventional electric baseboard heating and the other one supported by Electric Thermal Storage (ETS); the ETS is employed to optimize the local energy utilization pursuing the peak shaving of residential consumption profile. Simulations of the proposed architecture using the Energetic Macroscopic Representation (EMR) demonstrate the potential of ETS technologies in future HEMS.
Some remarks on the definition of numbers  [PDF]
GK Palei,PK Karu
BIBECHANA , 2014, DOI: 10.3126/bibechana.v11i0.10398
Abstract: In this paper some remarks have been given on the definition of number. It is clear that Peano’s definition of a number and Frege-Russel definition of number are not satisfactory. Number states some things about the concept and not about the counted things themselves.
Some Remarks on Noncommutative Instantons  [PDF]
Nikolay A. Ivanov
Mathematics , 2015,
Abstract: We make some comments on noncommutative $U(N)$-instantons on $\mathbb{R}^4_{\theta}$. We elaborate on the equations for the ASD-connection for free modules. Further we make some remarks on the computation of the topological index of ADHM instantons.
Some remarks on Hodge symmetry  [PDF]
Kirti Joshi
Mathematics , 2014,
Abstract: I make some remarks on Hodge symmetry, and prove for instance that if $k$ is a perfect field of characteristic $p>0$ and $X/k$ smooth, proper and Hodge-Witt scheme, and Hodge de Rham sequence of $X$ degenerates at $E_1$ and $X$ has torsion-free crystalline cohomology, then Hodge symmetry holds for $X$.
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