Search results for "hill"
showing 10 items of 369 documents
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…
A methodology for sizing a trigeneration plant in mediterranean areas
2003
Combined heat and power production is an old and well-known technique for the rational use of energy and, thanks to more than fifty years of experience, the state of art can be considered very advanced from a technological point of view. Trigeneration, that is combined electric, heat and cooling energy production, is however a quite recent technology and is becoming economically viable thanks to the commercial spread of absorption chillers. In fact, a well-projected trigeneration plant can achieve better results than a cogenerative one. The CHCP plant benefits over CHP will be underlined, showing the effects of regularisation of annual thermal load curves generated by consumption for feedin…
Characterization of cooling loads in the wine industry and novel seasonal indicator for reliable assessment of energy saving through retrofit of chil…
2020
Abstract The food sector is a major consumer of energy and growing efforts are being made in the search for solutions that will guarantee the efficient and sustainable use of energy resources. Among the different sectors, wineries are attracting particular interest due to the continuous growth of the global market and production. Surveys conducted in the winemaking sector have highlighted the importance of performing accurate energy audits and have identified the installation of efficient refrigeration systems as a promising solution in a variety of cases. Unfortunately, the savings achievable by efficient cooling technologies are often estimated using simplified approaches which do not tak…
Energy and economic assessment of desiccant cooling systems coupled with single glazed air and hybrid PV/thermal solar collectors for applications in…
2009
Abstract This paper presents a detailed analysis of the energy and economic performance of desiccant cooling systems (DEC) equipped with both single glazed standard air and hybrid photovoltaic/thermal (PV/t) collectors for applications in hot and humid climates. The use of ‘solar cogeneration’ by means of PV/t hybrid collectors enables the simultaneous production of electricity and heat, which can be directly used by desiccant air handling units, thereby making it possible to achieve very energy savings. The present work shows the results of detailed simulations conducted for a set of desiccant cooling systems operating without any heat storage. System performance was investigated through h…
Exergoeconomic analysis as support in decision-making for the design and operation of multiple chiller systems in air conditioning applications
2020
Abstract Multiple-chillers systems represent viable solutions for medium/large-scale air conditioning applications characterized by variable cooling demand. The energy efficiency of such systems is influenced by the number of chillers, the combination of cooling capacities, and the load-sharing among the units. Large efforts have been devoted to developing efficient operation strategies for these systems, but rules of thumb are usually adopted for selecting cooling capacities thus leaving room for energy and economic savings. In this paper, exergoeconomic analysis is proposed as a promising method to identify near-optimal design and operation strategies, due to the capability of exergoecono…
Energy balance and life cycle assessment of small size residential solar heating and cooling systems equipped with adsorption chillers
2017
Abstract Solar heating and cooling systems for space heating and cooling are experiencing a growing trend and interest. However, the actual energy and environmental performance of small/medium size installations is not clearly foreseeable. In this paper, an analysis of such systems using adsorption chillers in different European climates is presented. Solar systems have been simulated in TRNSYS and compared to a conventional system employing a vapour compression unit. The results have been used for a Life Cycle Assessment (LCA) study, determining the potential impact during the whole life of the system, from raw materials supply to its end-of-life. The LCA has been carried out by using the …
Life cycle performance assessment of small solar thermal cooling systems and conventional plants assisted with photovoltaics
2014
Starting from the results of a Life Cycle Assessment 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 (PV). This study aims to provide a comprehensive compared investigation of these two families of solar assisted cooling systems (with solar thermal or PV). Results indicate that, in many cases, the systems with the PV grid connected plant performed best. In addition, two more configurations were investigated to further define the PV assisted systems, which minimise their interaction with the grid through the use of electricity storages. These systems performed…
An Investigation of the Seasonal Pattern of Mannitol Content in Deciduous and Evergreen Species of the Oleaceae Growing in Northern Sicily
2002
In several species of the Oleaceae, mannitol, already present at considerable levels, accumulates in response to stress. This family comprises both deciduous and evergreen species, and we investigated the role of mannitol in deciduous malacophyll and evergreen sclerophyll species growing under the same conditions in the field. The relationship between mannitol content and changes in rainfall or temperature was also studied. The mannitol content of leaves of Fraxinus ornus L., F. angustifolia Vahl., Olea europaea L. and Phillyrea media L. was determined by gas chromatography. Leaf samples were collected once a month for 1 year. In the two ash species, the seasonal pattern of mannitol content…
Clay-biosurfactant materials as functional drug delivery systems: Slowing down effect in the in vitro release of cinnamic acid
2017
Abstract The main objectives of the present paper were the preparation and characterization of new surfactant-modified clays and the evaluation of their potential applicability as drug delivery systems for the oral administration of the cinnamic acid (CA) drug. The organoclays (OC) were prepared by loading different amounts of the biocompatible nonionic polyoxyethylene sorbitan monolaurate surfactant (Tween20) onto K10 montmorillonite (Mt) clay and characterized through the construction of the adsorption isotherms by means of the spectrophotometric method. The performance of the prepared material was verified by gathering the adsorption isotherms of the cinnamic acid onto the Mt/Tween20 org…
Identifying conserved genes involved in crop tolerance to cold stress
2022
Low temperature is a limiting factor for crop productivity in tropical and subtropical climates. Cold stress response in plants involves perceiving and relaying the signal through a transcriptional cascade composed of different transduction components, resulting in altered gene activity. We performed a meta-analysis of four previously published datasets of cold-tolerant and cold-sensitive crops to better understand the gene regulatory networks and identify key genes involved in cold stress tolerance conserved across phylogenetically distant species. Re-analysing the raw data with the same bioinformatics pipeline, we identified common cold tolerance-related genes. We found 236 and 242 common…