1,720,984 research outputs found
Campus solare termico. Corso multimediale per la progettazione di impianti solari. 3 DVD-ROM
No full textGuida alla progettazione ed istallazione di impianti solari termic
Libro bianco "Sfide ed opportunità dello sviluppo rurale per la mitigazione e l’adattamento ai cambiamenti climatici" - Capitolo 7 Settore Energetico
No full textAcoustic optimization of windows and doors through sound intensity measurements
No full textISO 140-5 defines the procedures to evaluate the sound insulation of façades obtaining the
global value D2m,nT,w. Moreover, each component of the façade can be characterized in laboratory
by means of its airborne sound insulation R using the methodology given by ISO
10140, and the weighted sound reduction index RW calculated using ISO 717-1. It is possible
to deepen the analysis of the façade components behavior using sound maps obtained through
sound intensity measurements. These are used to locate sound leakages and, in general, to
have a clear view of the performance of the tested element sub-components. The paper, after
a brief description of the method and the instruments used, presents the results of several
campaigns executed on different moveable parts of a building’s envelope: windows, doors
and minor components such as rolling shutter boxes. Thanks to the various case-studies presented,
it is demonstrated how the sound intensity measurements – using P-P probes - could
bring to not negligible improvements both on the design and the installation of the investigated
components. Finally, a different technique for measuring sound intensity passing through
a window is presented, using a P-U (Pressure - Velocity) probe
Development of a greenhouse gas accounting GIS-based tool to support local policy making - Application to an Italian municipality
No full textClimate change is the issue of the century and, according to Agenda 21, local actions are essential to impact global mitigation of greenhouse gases (GHG) emissions (“think globally, act locally”). However, in order to plan and implement effective, sustainable actions, local authorities need detailed information on their GHG emissions and their sources. This paper presents the work that led to the development of a GIS-based tool for local GHG accounting, which provides data for local decision-makers in an innovative manner different from traditional GHG inventories. The original aspects of the study are the geo-referencing of all results and the possibility of calculating all emissions (carbon sources) and removals (carbon sinks) with input data of different accuracy
Noise mapping and Action Plan realization within LIFE+ “NADIA” project
No full textNADIA (Noise Abatement Demonstrative and Innovative Actions and information to the public, LIFE 2009 ENV/IT/000102) is a project funded by the European Commission Directorate General "Environment" as part of the announcement Life + 2009 dealing mainly with the topic of road traffic noise. Detailed information on the project can be found on the project website [1] and in [2, 3].
The areas analysed in the project are 5 roads managed by the Provinces of Genova, 3 managed by the Province of Savona and parts of the agglomerations of Prato and Vicenza. Due to their traffic volume (for roads: higher than 3 million vehicles/year) or number of inhabitants (for agglomerations: higher than 100.000), the European Directive 2002/49/EC [4], implemented in Italy by the Legislative Decree n°194/2005 [5], imposes the realization of Strategic Noise Maps and Noise Action Plans for each of the considered areas.
During Action n°2 of the project, data were collected for the realization of noise maps and the evaluation of the indicator “population exposed to noise” of the considered roads/agglomerations. Noise mapping activities were performed in Action n°3. The results of these activities are reported respectively in the Deliverable 1 and 3 of the project, available on the NADIA project website [1].
The results of the noise simulations are now being used for the realization of Noise Action Plans (Action n°4). The paper reports the methodology that is being developed for their realization in the framework of the NADIA projec
Un impianto sperimentale ad assorbimento alimentato da energia solare
No full textPresso i laboratori di Fisica Tecnica della Facoltà di Ingegneria di Perugia, negli ultimi anni, si sono effettuati studi sulle prestazioni di una macchina frigorifera ad assorbimento ad Acqua-Bromuro di Litio. I risultati delle diverse campagne sperimentali condotte hanno evidenziato la possibilità di poter alimentare il gruppo frigorifero con temperature prossime a 70°C, rendendo proponibile l’impiego di energia solare per la produzione dell’acqua calda di alimentazione. Pertanto, si è sviluppato un codice di calcolo che ha permesso di simulare il funzionamento del gruppo frigorifero con un sistema integrato di alimentazione termica comprendente dei collettori solari ad elevata efficienza.
Il lavoro presenta i risultati delle simulazioni effettuate ed in particolare uno studio parametrico sull’influenza di diversi parametri (tipo di collettore,volume del serbatoio di accumulo, entità della superficie di captazione) sulla copertura del fabbisogno termico della macchina. I risultati ottenuti incoraggiano la prosecuzione della ricerca mediante la realizzazione dell’impianto e la relativa verifica sperimentale
High performance building envelopes with retro-reflective materials
No full textHighly reflective materials have been proposed as a strategy for energy consumption reduction in buildings and outdoor comfort improvement (i.e. urban heat island mitigation). Common cool materials’ high reflectivity allows to reduce surface temperature and thus cooling energy consumption in buildings. However, since they reflect energy diffusively in the hemisphere, most of the energy can be trapped within the urban canopy, in case of deep urban canyons and multiple reflections between buildings of different heights. Retro-reflective (RR) materials are proposed as new highly reflective materials for the building skin since they reflect most of the striking energy backward towards the incoming direction. RR directional properties allow to reduce the amount of energy trapped within urban canyons and urban canopies. Several studies are focused on the properties and beneficial effects of RR materials for building application. In this work the properties of retroreflective materials are presented. An analysis of the state of the art of materials for building application is proposed. Furthermore, opportunities and potentialities of RR materials compared to common cool materials are discussed from energy and environmental point of view. A discussion is proposed about their effectiveness and convenience in different urban patterns and for different optic properties and global reflectance
Remote Sensing Techniques for Urban Heating Analysis: A Case Study of Sustainable Construction at District Level
No full textIn recent years, many new districts in urban centres have been planned and constructed to reshape the structure and functions of specific areas. Urban regeneration strategies, planning and design principles have to take into account both socioeconomic perspectives and environmental sustainability. A district located in the historical city centre of Terni (Italy), Corso del Popolo, was analysed to assess the construction effects in terms of surface urban heat island (SUHI) mitigation. This district is an example of urban texture modification planned in the framework of the regeneration of the ancient part of the town. The changes were realised starting from 2006; the new area was completed on June 2014. The analysis was carried out by processing Landsat 7 ETM+ images before and after the interventions, retrieving land surface temperature (LST) and albedo maps. The map analysis proved the SUHI reduction of the new area after the interventions: as confirmed by the literature, such SUHI mitigation can be ascribed to the presence of green areas, the underground parking, the partial covering of the local roadway and the shadow effect of new multi-storey buildings. Moreover, an analysis of other parameters linked to the impervious surfaces (albedo, heat transfer and air circulation) driving LST variations is provided to better understand SUHI behaviour at the district level. The district regeneration shows that wisely planned and developed projects in the construction sector can improve urban areas not only economically and socially, but can also enhance the environmental impact
Experimental investigation on CO2methanation process for solar energy storage compared to CO2-based methanol synthesis
Full text linkThe utilization of the captured CO2 as a carbon source for the production of energy storage media offers a technological solution for overcoming crucial issues in current energy systems. Solar energy production generally does not match with energy demand because of its intermittent and non-programmable nature, entailing the adoption of storage technologies. Hydrogen constitutes a chemical storage for renewable electricity if it is produced by water electrolysis and is also the key reactant for CO2 methanation (Sabatier reaction). The utilization of CO2 as a feedstock for producing methane contributes to alleviate global climate changes and sequestration related problems. The produced methane is a carbon neutral gas that fits into existing infrastructure and allows issues related to the aforementioned intermittency and non-programmability of solar energy to be overcome. In this paper, an experimental apparatus, composed of an electrolyzer and a tubular fixed bed reactor, is built and used to produce methane via Sabatier reaction. The objective of the experimental campaign is the evaluation of the process performance and a comparison with other CO2 valorization paths such as methanol production. The investigated pressure range was 2–20 bar, obtaining a methane volume fraction in outlet gaseous mixture of 64.75% at 8 bar and 97.24% at 20 bar, with conversion efficiencies of, respectively, 84.64% and 99.06%. The methanol and methane processes were compared on the basis of an energy parameter defined as the spent energy/stored energy. It is higher for the methanol process (0.45), with respect to the methane production process (0.41–0.43), which has a higher energy storage capability
Experimental Investigation on the Effect of Phase Change Materials on Compressed Air Expansion in CAES Plants
No full textThe integration of renewable energy in the electrical grid is challenging due to the intermittent and non-programmable generated electric power and to the transmission of peak power levels. Several energy storage technologies have been studied to find a solution to these issues. In particular, compressed air energy storage (CAES) plants work by pumping and storing air into a vessel or in an underground cavern; then when energy is needed, the pressurized air is expanded in an expansion turbine. Several CAES configurations have been proposed: diabatic, adiabatic and isothermal. The isothermal process seems to be the most promising to improve the overall efficiency. It differs from conventional CAES approaches as it employs near-isothermal compression and expansion. Currently, there are no commercial isothermal CAES implementations worldwide, but several methods are under investigation. In this paper, the use of phase change materials (PCM) for isothermal air expansion is discussed. Air expansion tests in presence of PCM were carried out in a high-pressure vessel in order to analyze the effect of PCM on the process. Results show that in presence of PCM near isothermal expansion conditions occur and therefore they affect positively the value of the obtainable expansion work
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