Search results for "NEWA"
showing 10 items of 2491 documents
Experimental and numerical analysis of a backpressure Banki inline turbine for pressure regulation and energy production
2020
Abstract Water distribution networks have become, in recent years, a major opportunity for the harvesting of renewable energy, which is otherwise dissipated though hydrovalves installed for discharge and pressure regulation. Mini and micro hydroturbines have the capability of providing the same functionality of hydrovalves, producing at the same time a relevant amount of electric power. In this paper a 10 kW prototype of a new compact in-line turbine, named Power Recovery System (PRS), has been designed, constructed and tested in the hydraulic laboratory of the University of Palermo. The proposed device is a Banki-type micro-turbine, with positive outflow pressure and a mobile regulating fl…
A study on forecasting electricity production and consumption in smart cities and factories
2019
Abstract The electrical power sector must undergo a thorough metamorphosis to achieve the ambitious targets in greenhouse gas reduction set forth in the Paris Agreement of 2015. Reducing uncertainty about demand and, in case of renewable electricity generation, supply is important for the determination of spot electricity prices. In this work we propose and evaluate a context-based technique to anticipate the electricity production and consumption in buildings. We focus on a household with photovoltaics and energy storage system. We analyze the efficiency of Markov chains, stride predictors and also their combination into a hybrid predictor in modelling the evolution of electricity producti…
Evaluation of the Economic and Environmental Performance of Low-Temperature Heat to Power Conversion using a Reverse Electrodialysis – Multi-Effect D…
2019
In the examined heat engine, reverse electrodialysis (RED) is used to generate electricity from the salinity difference between two artificial solutions. The salinity gradient is restored through a multi-effect distillation system (MED) powered by low-temperature waste heat at 100 °C. The current work presents the first comprehensive economic and environmental analysis of this advanced concept, when varying the number of MED effects, the system sizing, the salt of the solutions, and other key parameters. The levelized cost of electricity (LCOE) has been calculated, showing that competitive solutions can be reached only when the system is at least medium to large scale. The lowest LCOE, at a…
Design, assembly and characterization of silicide-based thermoelectric modules
2016
ID: 1143 In: Energy conversion and management, 13-21. Summary: Highlights•Novel silicide-based thermoelectric modules were experimentally investigated.•The modules produced high power of 1.04 W at 405 °C and 3.24 W at 735 °C.•An estimated module efficiency of 5.3% represent the highest reported for silicide systems.AbstractSilicides have attracted considerable attention for use in thermoelectric generators due mainly to low cost, low toxicity and light weight, in contrast to conventional materials such as bismuth and lead telluride. Most reported work has focused on optimizing the materials properties while little has been done on module testing. In this work we have designed and tested mod…
Subtractive versus mass conserving metal shaping technologies: an environmental impact comparison
2015
The scientific studies in the domain of environmental sustainability of metal processing technologies predominantly focus on conventional material removal processes, as milling and turning. Despite some exceptions, many other non-machining technologies, such as metal forming processes, are still not well documented in terms of their energy and resource efficiency. Moreover, to properly evaluate the environmental impact of a given process, a standing-alone approach is no longer sufficient. In order to offer a valuable contribution in the domain of metal shaping sustainability, the present paper proposes a thorough methodology entailing to compare, from the environmental point of view, two tr…
Analyses of innovative glass blocks for BIPV: assessment of thermal and optical performance
2015
This paper illustrates the results of the performance analyses conducted on an innovative glass block integrated with thirdgeneration dye-sensitised solar cells (DSCs), designed to enable the construction of translucent and sustainable building envelopes. The analyses include the simulation of both thermal and optical performance with regard to different configurations of the photovoltaic (PV)-integrated glass block, and the results obtained are presented using two different programs: Comsol Multiphysics and WINDOW. The configurations may differ – for example, because of the position of the module inside the glass block, the type of DSC module used (composition, transparency, design) and th…
Simulation of a single-phase five-level cascaded H-Bridge inverter with multicarrier SPWM B-Spline based modulation techniques
2017
Multilevel Power Inverters are now often used to convert DC to AC voltage waveform. This kind of converter allows high power quality with low output harmonics and lower commutation losses with respect to the traditional ones in order to optimize this aspect. This paper presents a novel simulation analysis of the Multicarrier Sinusoidal Pulse Width Modulation (MC SPWM) techniques B-Spline functions based to control the switches of five-level single-phase cascaded H-bridge inverter. In order to verify the performance of the converter, the harmonic content of the voltage due to modulation techniques has been taken into account. Results highlight the comparison between different B-Spline functi…
New approach for harmonic mitigation in single-phase five-level CHBMI with fundamental frequency switching
2017
The main objective of this paper is to study and analyse the voltage output waveform of a multilevel inverter, to suggest a new approach for harmonic mitigation improving the converter performance. These last type of converters represent a new technology in the field of DC/AC electrical energy conversion, presenting advantages respect to the traditional converters. In fact, the multilevel power converters present a low harmonic content and a high voltage level. The paper considers a five-level single-phase cascaded H-bridge inverter and fundamental frequency modulation techniques. The voltage waveform analysis has allowed to identify a working area of the converter where there are lowest va…
Experimental analysis with FPGA controller-based of MC PWM techniques for three-phase five level cascaded H-bridge for PV applications
2016
The FPGA represents a valid solution for the design of control systems for inverters adopted in the field of PV systems because of their high flexibility of use. This paper presents an experimental analysis of the MC SPWM techniques for a three-phase, five-level, cascaded H-Bridge inverter with FPGA controller-based. Several control algorithms are implemented by means of the VHDL programming language and the output voltage waveforms obtained from the main PWM techniques are compared in terms of THD%. Simulation and experimental results are analysed, compared and discussed.
Energetic Sustainability Using Renewable Energies in the Mediterranean Sea
2016
The paper is focused on the analysis of the electrical energy sector in the Maltese islands, focusing on the employment of Renewable Energies in order to increase its energy independence. The main renewable source here proposed is wave energy: thanks to its strategic position, Malta will be able to generate electrical energy through the use of an innovative type of Wave Energy Converter (WEC) based on the prototype of linear generator designed and developed by the University of Palermo. This new technology will be able to cut down the electrical energy production from traditional power plants and, consequently, the greenhouse gas emissions (GHG). Wave energy source and off-shore photovoltai…