Search results for "Chiller"
showing 10 items of 59 documents
Pensar Históricamente : la evaluación en la PAU de Historia de España
2016
La Tesis Doctoral analiza el grado de desarrollo de pensamiento histórico alcanzado por los alumnos preuniversitarios, tomando como referencia la evaluación externa realizada tras finalizar 2o de Bachillerato. Dos han sido las fuentes de información fundamentales en nuestra investigación. Por una parte, los protocolos de examen de las pruebas de Historia de España propuestas por las universidades de las 17 Comunidades Autónomas. Y por otra, las respuestas de los alumnos, sobre una muestra de 300 exámenes, seleccionada de las Universidades de Valencia y Santiago de Compostela. Se trata de una investigación que nos ha exigido combinar diferentes métodos de investigación, cuantitativos y cuali…
Energy-saving potential of ground source multiple chillers in simple and hybrid configurations for Mediterranean climates
2022
Air conditioning accounts for a large share of energy usage in residential and tertiary sectors. Renewable energy technologies offer promising solutions to reduce the environmental impacts of meeting buildings’ energy loads. The possibility of using the soil as a thermal reservoir for heating and cooling systems has gained growing attention in the last decade due to its high potential for energy saving. In this paper, the benefits achievable using ground source chillers for air conditioning in an office building located in Southern Italy are discussed. A multiple chillers system coupled with a borehole heat exchanger is investigated and compared to conventional air-cooled and water-cooled s…
Über die frühen Werke von Carl Gotthard Graß in der Akademischen Bibliothek der Universität Lettlands, über die Freundschaft, Antiquarismus in der Ge…
2020
Las aportaciones de la Historia del Arte al proceso educativo intercultural: posibilidades y limitaciones
2016
La Historia del Arte es una asignatura adecuada para la consecucion de objetivos interculturales en Bachillerato. Las producciones artisticas de una sociedad reflejan las distintas culturas en contacto. Si se tiene en cuenta que el Bachillerato supone una preparacion para el acceso a la universidad, el docente no puede olvidar que el objetivo principal es conseguir cierto grado de madurez en el estudiante. Este articulo intenta mostrar como esta asignatura podra convertirse en el nucleo educativo intercultural en Bachillerato, mediante un analisis legislativo y el establecimiento de lineas de actuacion docente concretas. Se ha podido comprobar como una metodologia que parte de la reflexion …
An integrated approach based on Life Cycle Assessment and Thermoeconomics: Application to a water-cooled chiller for an air conditioning plant
2018
Abstract A large number of methods for energy systems analysis were developed in the last decades, aimed at acquiring an in-depth understanding of plant performances and enabling analysts to identify optimal design and operating conditions. In this work an integrated approach based on Life Cycle Assessment and Thermoeconomics is proposed as a method for assessing the exergo-environmental profile of energy systems. The procedure combines the capabilities of these two techniques, to account simultaneously for aspects related to thermodynamics of energy conversion processes and to the overall impacts along the plant life cycle related to other phases, i.e. from raw material extraction to the d…
Assessing the Energy-Saving Potential of a Dish-Stirling Concentrator Integrated into Energy Plants in the Tertiary Sector
2021
Energy consumed for air conditioning in residential and tertiary sectors accounts for a large share of global use. To reduce the environmental impacts burdening the covering of such demands, the adoption of renewable energy technologies is increasing. In this regard, this paper evaluates the energy and environmental benefits achievable by integrating a dish-Stirling concentrator into energy systems used for meeting the air conditioning demand of an office building. Two typical reference energy plants are assumed: (i) a natural gas boiler for heating purposes and air-cooled chillers for the cooling periods, and (ii) a reversible heat pump for both heating and cooling. For both systems, a dis…
Energy performance evaluation of a demo solar desiccant cooling system with heat recovery for the regeneration of the adsorption material
2012
Abstract Since July 2008, a Solar Desiccant Evaporative Cooling (DEC) system has been operating as a test plant at the solar laboratory of the Dipartimento di Energia (ex DREAM) of the University of Palermo. The system is composed of an air handling unit (AHU) designed for ventilation of the laboratory coupled with a radiant ceiling that provides most of the required sensible cooling/heating energy. Flat plate collectors deliver part of the regeneration heat of the desiccant wheel during the summertime and are used for space heating during the wintertime. The system was designed for high humidity loads because of the typical climate conditions at the site and the need to support a radiant c…
Scope-Oriented Thermoeconomic analysis of energy systems. Part I: Looking for a non-postulated cost accounting for the dissipative devices of a vapou…
2010
Abstract The authors of the main thermoeconomic methodologies developed in the last two decades have recently focused their efforts on the analysis of dissipative devices, i.e. those components whose productive purpose is neither intuitive nor easy to define. Coherent and unanimously accepted cost structures have been identified for dissipative components, while ambiguities still exist as concerns the cost allocation principles to be adopted. Being this aspect evidently cost-influencing, accurate analyses focused on the subjectivity of results are needed. This paper is structured in two parts. In the Part I an in-depth study of some critical issues arising from the thermoeconomic analysis o…
A Validation Methodology for a Combined Heating Cooling and Power (CHCP) Pilot Plant
2004
A great number of variables significantly influence the energetic, environmental and economic results of CHP (Combined Heating and Power) and CHCP (Combined Heating Cooling and Power) plants operation, and as a consequence their project activity is rather complex. In order to select the best layout and properly size the machines, detailed data on hourly electric, thermal, and cooling demand are necessary, so that a series of plant life cycle simulations may have to be carried out. Unfortunately, such detailed data are rarely available, because energy consumptions data for existing buildings are usually derived from aggregated monthly or bimonthly gas and electricity bills. Even more difficu…
Life Cycle Assessment Performance Comparison of Small Solar Thermal Cooling Systems with Conventional Plants Assisted with Photovoltaics
2012
Abstract Life Cycle Assessment (LCA) allows for the consideration of energy consumption and environmental impacts associated with all the stages of a product's life, from the cradle to the grave . Starting from the results obtained in the IEA SHC Task 38 framework for the LCA of small solar assisted heat driven chillers, the application of such methodology has been extended to systems with a conventional compression chiller assisted by a photovoltaic plant. This study aims to provide a more comprehensive investigation through a comparison of these two families of solar assisted cooling systems (with solar thermal or PV), which is an important topic for studies concerning the research of eff…