Search results for "020209 energy"
showing 10 items of 1300 documents
A procedure to evaluate the seven parameters of the two-diode model for photovoltaic modules
2019
Abstract The paper presents an analytical procedure to calculate the seven parameters of the two-diode model of photovoltaic (PV) panels for any value of the solar irradiance and cell temperature. Six parameters (the photocurrent, the diode reverse saturation currents, the quality factor of the first diode and the series and shunt resistances), are evaluated by solving the equations related to the properties of the main points of the current-voltage (I-V) characteristics. The further information, necessary to calculate the entire set of seven truly independent parameters, is based on two conditions that have to be simultaneously satisfied: 1) the exclusion of negative values of the model pa…
An accurate one-diode model suited to represent the current-voltage characteristics of crystalline and thin-film photovoltaic modules
2020
Abstract In this paper a new one-diode model, conceived in order to be used to represent the current-voltage curves of both crystalline and thin-film photovoltaic modules, is presented. The model parameters are calculated from the information contained in the datasheets issued by manufactures by means of simple iterative procedures that do not require the assumption of simplifying hypotheses. Some innovative relations describing the dependence of the parameters from the solar irradiance and cell temperature are adopted in order to permit the model to reliably simulate the electrical behaviour of photovoltaic devices operating in real conditions. The ability of the model to calculate the cur…
Electrochemical pH Control at Gold Nanowires
2018
In this work, interdigitated arrays of nanowire electrodes are used with one array acting as the working electrode while the other is used to generate the required protons. Finite element simulations of the pH control electrodes were performed to provide insight on the generation and subsequent diffusion of protons. This informed the inter-tine spacing of the electrodes used.. This electrochemical pH control method was then used to enable the detection of analytes of interest.
Photoelectrochemical evidence of nitrogen incorporation during anodizing sputtering--deposited Al-Ta alloys.
2015
Anodic films were grown to 20 V on sputtering-deposited Al–Ta alloys in ammonium biborate and borate buffer solutions. According to glow discharge optical emission spectroscopy, anodizing in ammonium containing solution leads to the formation of N containing anodic layers. Impedance measurements did not evidence significant differences between the dielectric properties of the anodic films as a function of the anodizing electrolyte. Photoelectrochemical investigation allowed evidencing that N incorporation induces a red-shift in the light absorption threshold of the films due to the formation of allowed localized states inside their mobility gap. The estimated Fowler threshold for the intern…
Life Cycle Assessment of an Ambitious Renovation of a Norwegian Apartment Building to nZEB Standard
2018
Author's accepted manuscript. The upgrading of building infrastructure to modern standards represents a key tool for reducing global energy demand and emissions from buildings. In Norway, building upgrades have been prioritized despite the relatively low carbon intensity of the Norwegian energy mix through various incentive programs and continual improvement in building standards. Prioritizing upgrades is important as up to 90% of the existing Norwegian building stock is expected to remain standing by the year 2050. The overall impact of upgrading buildings is expected to be a net benefit to the environment but this is primarily in operation, and many studies on energy do not include the ma…
A calcined clay fixed bed adsorption studies for the removal of heavy metals from aqueous solutions
2021
Abstract A natural clay material from southern Tunisia was used as a low cost sorbent in a column-wise removal of metal pollutants. This is fundamentally important for a sustainable wastewater treatment strategy. This work has been performed within the framework of a project aiming to the valorization of natural geomaterials, from Tunisia, in several environmental applications. Column adsorption experiments were carried out for a better production of cleaner effluents and further understanding of the main mechanisms involved in the removal process, through a dynamic methodology, that would allow an industrial scale treatment. A calcined clay sample was used as an adsorbent for the removal o…
Pricing of electricity futures based on locational price differences : The case of Finland
2018
We find that the pricing of Finnish electricity market futures has been inefficient during the latest 10 years, when the trading volumes of Electricity Price Area Differentials (EPADs) have more than doubled. Even though the calculated futures premium on EPADs is related to some risk measures and the variables capturing the demand and supply conditions in the spot electricity markets, there has been a significant positive excess futures premium in the Finnish market, and financial market participants should have been able to utilize this also in economic terms. This finding is new and relevant for the participants of the Nordic electricity markets also in the future, because both the specul…
EUA and sCER Phase II Price Drivers: Unveiling the reasons for the existence of the EUA-sCER spread
2011
International audience; This article studies the price relationships between EU emissions allowances (EUAs) - valid under the EU Emissions Trading Scheme (EU ETS) - and secondary Certified Emissions Reductions (sCERs)--established from primary CERs generated through the Kyoto Protocol's Clean Development Mechanism (CDM). Given the price differences between EUAs and sCERs, financial and industrial operators may benefit from arbitrage strategies by buying sCERs and selling EUAs (i.e. selling the EUA-sCER spread) to cover their compliance position as industrial operators are allowed to use sCERs towards compliance with their emissions cap within the European system up to 13.4%. Our central res…
A bottom-up harmonized energy-environmental models for europe (BOHEEME): A case study on the thermal insulation of the EU-28 building stock
2021
Abstract The paper presents a methodological approach, called “BOttom-up Harmonized Energy-Environmental Models for Europe” (BOHEEME), that combines bottom-up modeling, energy dynamic simulation, and life cycle assessment for evaluating and comparing the energy and environmental effects of different renovation strategies of the residential EU building stocks, from micro to the macro level. The study defines 672 building models representative of the residential EU-28 building stocks built before 2010, called archetypes, and the improvement of their envelope, applying different insulation materials from a traditional one to bio-based materials and studying their environmental effects via LCA.…
Artificial neural network decision support tool for assessment of the energy performance and the refurbishment actions for the non-residential buildi…
2017
The public buildings sector represents one of the most intensive items of EU energy consumption; the application of retrofit solutions in existing buildings is a crucial way to reduce its impact. To facilitate the knowledge of the energy performance of existing non-residential buildings and the choice of the more adequate actions, Public Administrations (PA) should have the availability of proper tools. Within the Italian project "POI 2007-13", a database and a decision support tool, for easy use, even to a non-technical user, have been developed. A large set of data, obtained from the energy audits of 151 existing public buildings located in four regions of South Italy have been analysed, …