Search results for "Efficient"
showing 10 items of 1603 documents
A data-driven methodology to support pump performance analysis and energy efficiency optimization in Waste Water Treatment Plants
2017
Abstract Studies and publications from the past ten years demonstrate that generally the energy efficiency of Waste Water Treatment Plants (WWTPs) is unsatisfactory. In this domain, efficient pump energy management can generate economic and environmental benefits. Although the availability of on-line sensors can provide high-frequency information about pump systems, at best, energy assessment is carried out a few times a year using aggregated data. Consequently, pump inefficiencies are normally detected late and the comprehension of pump system dynamics is often not satisfactory. In this paper, a data-driven methodology to support the daily energy decision-making is presented. This innovati…
Studies Energy Efficiency of the Renewable Sources use Considering Climate in Latvia
2015
AbstractThe paper discusses problems of energy supply of buildings using renewable sources given the local climatic conditions. The meteorological conditions in Latvia and Riga for last year were analyzed. In paper shows examples of energy efficient buildings allowing that to provide comfort temperature and indoor air quality. The structure and composition of local building materials, providing good thermal insulation are described. The heating systems for test buildings using renewable energy sources were investigated. The assessment of the energy efficiency of the “air-air” and “air-water” heat pumps is studied.
Energy efficient operation in smart grids: optimal management of shiftable loads and storage systems
2012
In this paper, the authors analyze the impact of the participation of customers to the sustainable implementation of energy rational strategies in microgrids. The management of shiftable loads is compared to the control of real and reactive storage systems in smart grids. An optimization algorithm is used as analysis tool to assess the impact of such control variables in different conditions. The results clearly indicate that if shiftable loads are of suitable size, they have a more promising as tools to both reduce losses and to flatten the peak load through the HV/MV bus. Many tests have been carried out on a real experimental MV system in the area of Rome Italy.
Advanced Control Structure for Energy Management in Ground Coupled Heat Pump HVAC System
2008
Abstract Over the last 15 years, computerized controls have become more and more common in our homes. The smart home looks at expanding the use of the computers into the difference parts of the home, creating a network that can be easily and conveniently controlled. The use of computer controls removes the need to actually flick a switch and allows elements of the home to respond automatically to the people living in it. Successful control and heating ventilating and air-conditioning (HVAC) systems is a primary concern in building project: in order to achieve the required comfort and energy efficiency goals, a lot of variables must be coordinated and kept at particular pre-designed operatio…
Optimization of hybrid – ground coupled and air source – heat pump systems in combination with thermal storage
2010
Ground coupled heat pumps are attractive solutions for cooling and heating commercial buildings due to their high efficiency and their reduced environmental impact. Two possible ideas to improve the efficiency of these systems are decoupling energy generation from energy distribution and combining different HVAC systems. Based on these two ideas, we present several HVAC configurations which combine the following equipments: a ground coupled heat pump, an air to water heat pump and a thermal storage device. These HVAC configurations are linked to an office building in a cooling dominated area in order to evaluate in these conditions the total electrical consumption of each configuration to o…
Single thermal zone balance solved by Transfer Function Method
2005
We present an algorithm that uses the Z-transform operator to face the problem of heat transmission in a single thermal zone composed by multilayered walls. The method is very flexible and could be adopted to calculate the transfer function coefficients able to simulate the thermal behaviour of a room in free floating. Knowing the transfer function coefficients, it is possible to simulate the dynamic profile of each inner surfaces temperature and furthermore of the inner air temperature. The proposed algorithm is fully described granting maximum clarity. The explicitness of all steps of the calculus make possible the definition of a method that is able to vary all of the calculus parameters…
Concurrent optimization of size and switch-on priority of a multisource energy system for a commercial building application
2015
Abstract In recent years, the governments of most nations have pledged to (i) limit carbon dioxide emissions, (ii) reduce primary energy consumption by increasing production, distribution and end-use efficiency and (iii) increase the utilization of renewable energy sources. In general, these goals are pursued separately by law, by subsidizing renewable energy technologies, reducing the demand or using high efficiency technologies. In this context, multi-source systems for the fulfillment of energy demands are highly advantageous because they are based on different technologies which use renewable, partially renewable and fossil energy sources. However, the main issues of multi-source system…
Nanotechnology for Photovoltaic Cells and Energy Efficiency
2015
Abstract. The intent of this paper is to connect science and technology in order to demonstrate how, in the field of on photovoltaic technologies, thin film solar cells have been the focus of many research facilities in recent years that are working to decrease manufacturing costs and increase cell efficiency. New research suggests that it might be possible to add a nanoscopic relief pattern to the surface of solar cells that makes them non-reflective significantly boosting efficiency and at the same time making them highly non-stick and self-cleaning. The paper presents the challenges and approaches to engineer the active layer of the cell, in order to obtain cells made up of components as…
Turbulence model effect on heat exchange characteristics through the neutron beam window for European spallation source
2011
PurposeThe purpose of this paper is to compare k‐ω shear‐stress transport (SST) and large eddy simulation (LES) turbulence model application effect on numerical computation of flow pattern and heat exchange characteristics through the neutron beam window region for European spallation source setup model.Design/methodology/approachTransient hydrodynamic and thermal calculations with appropriate heat sources are performed using both turbulence models and typical discrepancies in flow and thermal patterns are discussed, as well as, simulation results are qualitatively compared with experimental data for heat transfer coefficient distribution α at the window surface.FindingsContribution of grea…
Wine label design as a strategic tool to attract consumers. A marketing study on Sicilian wine positioning
2013
Negli ultimi anni il packaging e stato considerato dalle aziende vinicole uno tra i piu importanti strumenti del marketing. Infatti, grazie all’utilizzazione di immagini e testi, e possibile comunicare chiaramente al mercato messaggi coerenti con i prodotti, con i valori dell’azienda e con i target di consumatori di riferimento. In questo studio si e voluto conoscere quanto le etichette siano importanti per le cantine siciliane nelle scelte di posizionamento dei loro vini. Si e voluta, inoltre, misurare l’influenza che le etichette esercitano sui consumatori, indirizzando ed orientando le preferenze al momento dell’acquisto di un vino, senza tralasciare l’eventuale effetto attrattivo causat…