Search results for " generation."
showing 10 items of 1108 documents
Husk Energy Supply Systems for Sunflower Oil Mills
2020
Together with solar, wind, and hydro renewable energy sources (RES), biomass constitutes an integral part of the high-renewables electricity systems. Considerable feedstocks for electricity generation are process-based residues. Ukraine is the world leader in sunflower seed production, therefore, husk (a by-product of oil production) is a promising biofuel for combustion- based power plants. The plants consume primarily electricity and fossil fuels (natural gas or fuel oil) for steam production. Their usage affects the edible oil production cost and impacts on climate change. The above facts force us to look for alternatives. By-product (husk) utilization can reduce exhaustible energy consu…
The early careers of the second generations: a double ethnic penalty?
2016
International audience; Young people from North African origin have greater difficulty in finding employment than their counterparts of French origin. And once they do manage to find employment, their jobs tend to be of lower quality. Thus they appear to suffer from a double penalty linked to their origins which, aggravated by the crisis, does not seem to abate over time.
Quasi Phase Matched UV Second Harmonic Generation in Lithium Tantalate soft PE Waveguides
2008
We report on first experimental results on UltraViolet second-harmonic generation by first-order quasiphase-matching in a surface periodically poled proton exchanged Lithium Tantalate waveguide. We have achieved a good compatibility with alpha phase proton exchanged channel waveguides in Lithium Tantalate. We held the sample in a temperature controlled oven kept at a constant temperature of 250 °C, to reduce photorefractive damage. The pump source was a Ti-Sapphire laser with a tunability range of 700 - 980 nm and a 40-GHz linewidth. Continuous wave UV light at 365.4 nm was produced with a conversion efficiency of 6.6% W-1cm-2.
Uno strumento virtuale per il monitoraggio e il controllo di un impianto fotovoltaico a concentrazione
2014
In questa memoria si presenta una sintesi delle attività condotte nell'ambito del progetto SERPICO ("Sviluppo E Realizzazione di Prototipi di Inverter per impianti fotovoltaici a Concentrazione", PO-FESR Sicilia 2007-2013, Misura 4.1.1.2). Il progetto ha riguardato lo sviluppo di un prototipo di impianto fotovoltaico-termico a concentrazione e del relativo sistema di monitoraggio e controllo. Tale sistema permette di acquisire le quantità sia elettriche che termiche. Inoltre esso implementa un algoritmo per l'inseguimento solare utilizzato per ottimizzare la produzione di potenza.
Characterization of IP-Based Communication for Smart Grid Using Software-Defined Networking
2018
The smart grid (SG) approach is based on a strong interaction between the network communication infrastructure and the power grid. Usually the management of the infrastructure is done by the distribution system operators (DSOs) that are worried about the increasing managing complexity due to the presence of increasing number of distributed energy resources and electrical vehicles. The use of software-defined networking (SDN) may simplify the network configuration and management for DSO, as highlighted from previous research works. The objective of this paper is to introduce and characterize an internet protocol (IP)-based communication architecture with specialized SDN bridges operating als…
A PC-based instrument for automatic monitoring and control of a CPVT power plant
2014
A PC-based instrument has been developed for the monitoring and control of a concentrated photovoltaic and thermal (CPVT) power plant. The instrument allows acquiring both electrical and thermal quantities. Moreover it implements the solar tracking algorithm used to optimize the power production.
Sistemi di comunicazione e dispositivi di interfaccia per l'integrazione della generazione distribuita nelle smart grids
2014
L'integrazione della generazione distribuita (GD) nelle reti elettriche di distribuzione a media e bassa tensione uno degli elementi chiave per il pieno sfruttamento delle fonti energetiche rinnovabili (FER). Ci implica un ripensamento della gestione e del controllo delle reti elettriche , che devono passare da sistemi " passivi ", con flussi di potenza unidirezionali e un numero limitato di funzioni di monitoraggio e automazione, a reti attive e intelligenti (Òsmart gridsÒ). In tali sistemi, i flussi di potenza possono essere bi-direzionali e, se non correttamente gestiti, possono causare situazioni critiche, quali ad es. problemi di stabilit e di controllo della rete o funzionamento i…
Impact of non-programmable distributed generation in an islanded microgrid: the case study of Ustica
2022
The paper presents a systematic analysis of nonprogrammable distributed generation impact in an islanded microgrid Different issues have been analyzed, with a special focus on the most significant ones in a small islanded network. To this aim, the case study of Ustica island was considered A digital twin of the MV network was developed starting from the network topology data and the power measurement acquired in each secondary substation. Simulations were then performed in the hypothesis of a large increment of distributed generation installation into the network. A discussion is then reported on which are the main technical issues to be faced in the considered case study.
SCOPE-Based Emulators for Fast Generation of Synthetic Canopy Reflectance and Sun-Induced Fluorescence Spectra
2017
Progress in advanced radiative transfer models (RTMs) led to an improved understanding of reflectance (R) and sun-induced chlorophyll fluorescence (SIF) emission throughout the leaf and canopy. Among advanced canopy RTMs that have been recently modified to deliver SIF spectral outputs are the energy balance model SCOPE and the 3D models DART and FLIGHT. The downside of these RTMs is that they are computationally expensive, which makes them impractical in routine processing, such as scene generation and retrieval applications. To bypass their computational burden, a computationally effective technique has been proposed by only using a limited number of model runs, called emulation. The idea …
Realization of time-resolved two-vacuum-ultraviolet-photon ionization
2009
International audience; Ultrafast dynamics of excited molecules is studied through time-resolved two-vacuum-ultraviolet (vuv)- photon ionization using a nonlinear volume autocorrelator unit. The two-vuv-photon process is induced by the intense fifth harmonic radiation of a femtosecond Ti:sapphire laser. In a proof-of-principle experiment, ultrafast dynamics of excited ethylene and oxygen molecules are investigated. Molecular decay times are deduced by comparing the experimental data with the results of a numerical model that accounts for the spatial and temporal characteristics of the harmonic field. The present experiments pave a convenient way for time domain investigations in the vuv-xuv s…