59 research outputs found
Recovering industrial heritage: restoration of the wine cellar cooperative in Falset (Catalonia, Spain)
Awareness regarding conservation of industrial heritage is recent. Several policies have been adopted to start protecting these buildings because of their historic, artistic and scientific values. Wine cellars are an important example of industrial heritage in Catalonia due to the tradition of this product in the territory and the influence of Art Nouveau and Catalan ‘Noucentisme’ in their construction and style. The wine cellar in Falset, built by Cèsar Martinell in 1919, has recently been restored and still maintains its original function. This article analyses its history, its architectonic and construction characteristics, as well as the restoration process carried out in 2009, which consisted of recovering its original appearance and allowed to emphasize the architectural value of the building. This restoration is a prototypical example whose experience can be applied in other cases of restoration of wine cellars both for the characteristics of the building and for its good restoration practices. This restoration enabled the wine cellar to continue carrying out its original industrial function, providing suitable conditions to add a new cultural use as wellPeer ReviewedPostprint (author's final draft
Optimización térmica y energética de la doble fachada acristalada con ventilación mecánica en clima mediterráneo
El diseño de edificios siguiendo criterios de sostenibilidad y eficiencia energética se ha convertido en un imperativo en los países desarrollados, sobre todo a raíz de la Directiva europea 2010/31/UE sobre Eficiencia Energética en los Edificios, cuyo objetivo para el año 2019 es el de conseguir zero-emission buildings, es decir, edificios cuyo impacto sobre el entorno sea casi nulo, al ser autosuficientes energéticamente y no emitir gases de efecto invernadero.
En respuesta a esta corriente, la Doble Fachada Acristalada (DFA) representa una alternativa constructiva que, aplicada en entornos mediterráneos, supone una posible estrategia de diseño energéticamente eficiente para mejorar el comportamiento de las tradicionales fachadas de vidrio de uso tan extendido en los edificios de oficinas y comerciales de las grandes ciudades.
El estudio de la implantación de la DFA y su comportamiento ha sido un tema tratado extensamente en la última década. No obstante, la literatura disponible está muy restringida a casos de regiones de clima frío y templado de Europa y América del Norte, contexto en el cual pueden encontrarse casos de aplicación eficiente a nivel energético. Sin embargo, las experiencias de aplicación de DFA en zonas de clima mediterráneo arrojan posibles problemas de funcionamiento, sobre todo durante la estación cálida, debido al sobrecalentamiento de la entrepiel causado por la elevada radiación solar característica de este tipo de clima. Este fenómeno ocasiona que sea necesario un coste energético extra para obtener unas condiciones de confort adecuadas en el interior del edificio.
El estudio de la DFA requiere de una investigación exhaustiva de los fenómenos de transferencia de calor y fluidodinámicos involucrados. Para realizar un análisis apropiado de estos fenómenos, y gracias a la mejora de la potencia de cálculo de los ordenadores en los últimos años, han aparecido métodos que permiten abordar el problema de analizar el comportamiento de la DFA a través de la definición de modelos matemáticos que simplifican el modelo real. En esta línea, el uso de programas de simulación térmica zonal y multizonal, así como la utilización de programas de dinámica de fluidos computacional (CFD), se han destacado como herramientas útiles a la hora de modelizar los fenómenos fluidodinámicos y de transferencia de calor asociados a la DFA.
El objetivo general de esta tesis se centra en la optimización del comportamiento térmico y energético de una doble fachada acristalada con ventilación forzada (DFAV) horizontal y configuración constructiva fija, para su aplicación en edificios de oficinas localizados en zonas de clima mediterráneo. Dicha optimización, que se ha llevado a cabo mediante el software de simulación térmica zonal TAS, pretende resolver los posibles problemas de sobrecalentamiento en el interior del edificio generados cuando se aplica esta tipología de fachada en climas de alta radiación solar.
En el modelo analizado, la ventilación de la entrepiel de la fachada –que es la encargada de la evacuación del exceso de calor de la misma–, se supone a cargo de un sistema de recirculación del aire de climatización expulsado del edificio. Este sistema puede ser complementado, en caso de requerirse una mayor extracción de calor, por un equipo auxiliar que mediante la impulsión de aire exterior permita aumentar el caudal de aire a través de la entrepiel.
Por otro lado, se ha utilizado un modelo analítico simplificado –desarrollado a partir de las ecuaciones fundamentales de transferencia de calor–, que se ha evaluado en diversos puntos característicos del dominio para comprobar la exactitud de los resultados obtenidos a través de las simulaciones realizadas. Se ha concluido que, para estimar la efectividad de la DFAV a la hora de disminuir la demanda energética del edificio, este modelo matemático simplificado –que utiliza coeficientes de transmisión de calor combinados medios– puede considerarse válido. Además, las diferencias obtenidas con el modelo simulado son lo suficientemente reducidas para considerar que –a falta de un modelo experimental sobre el que validar los resultados obtenidos– dicho desarrollo matemático permite afirmar la bondad de los resultados obtenidos en el modelo de simulación.
Respecto al proceso de optimización de la DFAV se ha concluido que, para una oficina de características estándar, la fachada es el elemento clave que define el comportamiento termoenergético del edificio, de manera que su correcto diseño es fundamental para conseguir minimizar su consumo energético y alcanzar las mejores condiciones de confort térmico interior posibles. Así, en edificios con fachadas altamente vidriadas situados en entornos de elevada radiación solar como el mediterráneo, la utilización de vidrios que limiten las ganancias solares en el interior del edificio es básica para el control de la demanda de climatización del mismo. Contrariamente, el comportamiento del edificio empeora al sustituir el vidrio interior transparente por uno bajo emisivo, lo que prueba que, en ocasiones, la utilización de un vidrio de mayor calidad no supone un beneficio claro en cuanto a la disminución de la demanda del edificio en el cuál se instala. Además, se comprueba que la utilización de la DFAV frente al muro cortina tradicional permite mejorar las condiciones de demanda de climatización y de confort térmico alcanzadas en un edificio como el analizado.
Por último, se ha concluido que la aplicación de una estrategia de ventilación mixta a caudal variable en función de las necesidades de climatización de los espacios ocupados supone una mejora notable a nivel de reducción de la demanda de climatización global del edificio, aunque únicamente respecto al caso de DFA sin ventilar. Las mejoras respecto a los casos con la doble fachada ventilada con un caudal elevado de aire exterior son escasas. Así pues, la decisión de emplear un tipo u otro de ventilación de la entrepiel de la DFAV vendrá determinada por el análisis de coste de implantación contra la disminución de la demanda de climatización asociada a cada sistema. Las reducciones de la demanda de climatización obtenidas parecen descartar la instalación del sistema de recirculación de aire interior para ventilar la DFAV, al obtenerse escasas mejoras respecto a un sistema de ventilación con aportación de aire todo exterior.The building design in base of sustainability and energy efficiency criteria has become an imperative in developed countries, especially since the application of the European Directive 2010/31/EU on Energy Efficiency in Buildings, whose goal for 2019 is the achievement of zero-emission buildings, buildings with almost zero impact on the environment. In response to this trend, Double Glazed Facade (DGF) represents a constructive alternative that can improve the performance of traditional glass facades commonly used in commercial and offices buildings located in large cities.
The study of the DGF has been largely restricted to cases of cold and temperate climate regions in Europe and North America. In this context, many energy efficient applications can be found. However, the DGF application experiences in Mediterranean climate have shown potential performance problems, due to the facade overheating caused by high solar radiation characteristic of this type of weather. This phenomenon is responsible of the need of an extra energy cost for adequate comfort conditions inside the building.
The study of the DGF requires an intensive investigation of heat transfer phenomena involved. For a proper analysis of these phenomena, some methods which analyze the DFA behavior through mathematical models which simplify the real model can be used. In this line, the use of thermal simulation zonal programs and the use of computational fluid dynamics have emerged as useful tools when modeling physical phenomena associated to the DFA. The main objective of this thesis focuses on the optimization of the thermal and energy performance of a double skin facade with an horizontal forced ventilation scheme, and with a fixed structural design, for its application in office buildings located in areas with a Mediterranean climate. This optimization has been carried out with the thermal simulation software TAS. The facade ventilation of the analyzed model ¿which is res pons ible for the removal of the heat accumulated in the space between the two skins is generated by a system which recirculates the air expelled from the building. This system can be supplemented with an auxiliary system which drives outside air for increasing the air flow through the facade cavity.
On the other hand, a symplified analytical model developed from the fundamental equations of heat transfer has been used to check the accuracy of the results obtained through simulations. It has been concluded that such mathematical model allows us to affirm the goodness of the results obtained in the simulation model. Furthermore, it can be considered valid to estimate the effectiveness of DGF to decrease the energy demand of the building.
Regarding the DFAV optimization process, it has been concluded that, for an standard office building, the facade is the key element that defines the thermal behavior of the building. So, its correct design is essential for minimizing energy consumption and for achieving indoor thermal comfort conditions.
It is found that the use of DGF against traditional curtain wall can reduce the cooling demand and improve the thermal comfort in a building like the one analyzed. Moreover, it has been concluded that the application of variable flow hybrid ventilation causes a notable improvement to reduce overall cooling demand of the building when comparing with the unventilated DGF case. The analysis of the HVAC reductions seems to advise against the installation of an air recirculation system to ventilate the DGF cavity, because of the little improvement obtained over the use of a ventilation system only with exterior air supply. So the final decision to use a certain type of cavity ventilation will be determined by the analysis of implementation cost against the HVAC demand reduction for each system
Effects of the type of facade on the energy performance of office buildings representative of the city of Barcelona
The aim of this article is to analyze the energy efficiency issues of eight office buildings built in Barcelona. Using computer simulations to compare energy demand and level of indoor natural lighting, it is demonstrated that there are considerable differences in demand – in some cases more than double – depending on the type of facade, and these differences are not directly related to the economic cost of the construction solutions used. In all cases, the cooling demand represents more than 80% of the total climate control demand, and solar radiation is the parameter with the greatest effect. The overall solar factor of the facade stands out as a key variable to control to both reduce the overall energy needs of a building and separate the cooling demand from the orientation of the building. The level of natural lighting is a differentiating element only in cases that had similar thermal energy performance.Peer ReviewedPostprint (author's final draft
Gestió de l’aigua en el creixement de les ciutats
En el marc de l’assignatura d’Urbanisme i Serveis Urbans, en els darrers anys, fem especial incidència en la gestió de l’aigua en la urbanització de la ciutat tant en les zones habitades com en els polígons industrials.Peer Reviewe
Investigació i recerca en sostenibilitat i eficiència energètica dels edificis
L’elevat consum d’energia dels edificis representa un problema que no és possible d’assumir a llarg termini sense considerar mesures d’estalvi i eficiència energètica com a eines bàsiques cap al desenvolupament sostenible.
És per aquest motiu que des del Departament d’Enginyeria de la Construcció considerem com una qüestió cabdal la participació en aquesta problemàtica de l’alumnat de les assignatures que impartim, especialment en el cas de l’assignatura de Construccions Industrials.Peer Reviewe
Comportamiento térmico de un invernadero integrado en azotea en una ciudad mediterránea : resultados preliminares
La agricultura urbana (AU) es considerada una actividad esencial para el
desarrollo de las ciudades debido a que promueve la producción local,
ayuda a reducir los impactos ambientales del transporte y del embalaje de
alimentos y, sobre todo, provee seguridad alimentaria a las poblaciones urbanas
y contribuye a la cohesión social. Entre las diversas tipologías en las
que se presenta la AU, se encuentran los invernaderos implementados en
las azoteas de edificios urbanos (RTG’s, Rooftop Greenhouses), utilizando
superficies frecuentemente desaprovechadas y entre ellos los invernaderos
integrados en las azoteas (i-RTGs, Integrated Rooftop Greenhouses) que
reutilizan los flujos residuales de energía, agua y gases del invernadero o
del edificio para mejorar las condiciones ambientales en ambos espacios.
Existen numerosos ejemplos de RTG’s con un enfoque comercial y social
en E.U.A, Canadá y Japón, en este sentido pero con un enfoque académico
el invernadero integrado construido en la azotea del edificio ICTA-ICP (UAB, Barcelona, España, ICTA i-RTG), analiza desde un punto de vista de
la sostenibilidad el sistema de producción agrícola en zonas urbanas del
Mediterráneo a través de su interconexión con el resto del edificio. El ICTA
i-RTG reutiliza el calor residual del edificio, las concentraciones de CO2 y el
agua pluvial para reducir sus impactos ambientales.
En el marco del proyecto Fertilecity, esta contribución expone los resultados
preliminares del comportamiento térmico-energético del ICTA i-RTG
durante el año del 2015 en el clima mediterráneo. Para la caracterización del
comportamiento energético, las condiciones interiores y exteriores son monitoreadas
en términos de temperatura, humedad, radiación solar y otras
variables climáticas, mediante diversas sondas e instrumentos uniformemente
distribuidos dentro y fuera del edificio.
Los resultados preliminares indican que durante el invierno el calor residual
del edificio ayuda a mantener las condiciones ideales de temperatura para
la productividad del sistema de horticultura, presentando una diferencia
promedio de 10 ºC en comparación con las temperaturas registradas fuera
del edificio y en invernaderos convencionales. Durante la primavera y el
otoño se presentan las condiciones más estables para el cultivo y el verano
representa un reto debido a las altas temperaturas exteriores que influyen
en el edificio y el invernadero. Estos resultados indican que existe una mejora
térmica en relación a los invernaderos convencionales principalmente en
invierno y se espera en un futuro cuantificar la minimización del consumo
de energía no renovable directa en el ICTA-iRTG.Postprint (published version
Building-integrated rooftop greenhouses: an energy and environmental assessment in the mediterranean context
A sustainable and secure food supply within a low-carbon and resilient infrastructure is encapsulated in several of The United Nations’ 17 sustainable development goals. The integration of urban agriculture in buildings can offer improved efficiencies; in recognition of this, the first south European example of a fully integrated rooftop greenhouse (iRTG) was designed and incorporated into the ICTA-ICP building by the Autonomous University of Barcelona. This design seeks to interchange heat, CO2 and rainwater between the building and its rooftop greenhouse. Average air temperatures for 2015 in the iRTG were 16.5 °C (winter) and 25.79 °C (summer), making the iRTG an ideal growing environment. Using detailed thermophysical fabric properties, 2015 site-specific weather data, exact control strategies and dynamic soil temperatures, the iRTG was modelled in EnergyPlus to assess the performance of an equivalent ‘freestanding’ greenhouse. The validated result shows that the thermal interchange between the iRTG and the ICTA-ICP building has considerable moderating effects on the iRTG’s indoor climate; since average hourly temperatures in an equivalent freestanding greenhouse would have been 4.1 °C colder in winter and 4.4 °C warmer in summer under the 2015 climatic conditions. The simulation results demonstrate that the iRTG case study recycled 43.78 MWh of thermal energy (or 341.93 kWh/m2/yr) from the main building in 2015. Assuming 100% energy conversion efficiency, compared to freestanding greenhouses heated with oil, gas or biomass systems, the iRTG delivered an equivalent carbon savings of 113.8, 82.4 or 5.5 kg CO2(eq)/m2/yr, respectively, and economic savings of 19.63, 15.88 or 17.33 €/m2/yr, respectively. Under similar climatic conditions, this symbiosis between buildings and urban agriculture makes an iRTG an efficient resource-management model and supports the promotion of a new typology or concept of buildings with a nexus or symbiosis between energy efficiency and food production.Postprint (published version
Polyamide waste thermal and acoustic properties: experimental and numerical investigation on possible reuse for indoor comfort improvement
Referring to the circular economy model, end-of-life household materials (EoLHM) such as packaging, and clothes, could be converted into building elements – for example panels - with thermal and acoustic properties. Given the high availability almost anywhere, EoLHM represents an alternative to commercial insulating materials that, even though relatively cheap, cannot be afforded by disadvantaged people. The panels are intended for the refurbishment of existing buildings and, therefore, to be installed indoor. This paper presents a multidisciplinary analysis aimed at the characterization of polyamide 6.6 waste from the production of non surgical face masks. The analysis focuses on thermal and acoustic aspects that have determined experimentally by means of the hot plate with guard ring test, and the impedance tube technique respectively. Then, the influence of the panel position on the indoor operative temperature and the reverberation time has been analysed numerically. Results show that, from the thermal and acoustic point of view, this waste is suitable for the realization of building panels and the performance depends on the density and the thickness of the material. However, aspects such as the fire-resistance and the containment of the material need further investigation.Peer ReviewedPostprint (published version
Feasibility assessment of rooftop greenhouses in Latin America. The case study of a social neighborhood in Quito, Ecuador
Today, food security has a critical place in the government agendas of developing countries. In Latin American case, urban contexts have been subject to radical transformations in the last decades, most apparently through the expansion of social housing, which may limit or condition access to food for the neediest population. Nowadays, in Latin America, there are numerous cases of urban agriculture. Quito (Ecuador) stands out for the development of urban agriculture through the Participatory Urban Agriculture Project - AGRUPAR; initiative that has led to the implementation of orchards with organic production, raising of small animals, food processing and marketing of surpluses for food-nutrition security. Above all, it has transcended its urban and peri-urban intervention to rural areas, favoring the urban-rural connection. Also, worldwide the urban agriculture is developed in different forms, one of which is through crops protected by a greenhouse on the roofs: Rooftop greenhouse (RTG). This form of UA uses specific substrates for hydroponic crops and has modern irrigation systems often combined with rainwater harvesting and provides a unique opportunity to improve urban agriculture in Quito.
The purpose of this study is to identify the implementation potential of rooftop greenhouses in social neighborhoods in Quito. Standard methods to assess the potential use of rooftop greenhouses were adapted to a social neighborhood. The guidelines follow three steps: Step 1: Characterization based on criteria; Step 2: Available surface determination and Step 3: Production, self-sufficiency and self-supply. “La Comuna Santa Clara de San Millán” was selected as study area. The results showed that 33.2% (7.70¿ha) of the neighborhood rooftops had a short-term feasibility to install rooftop greenhouses, with the potential to produce 1,579,140 and 56,720¿kg/year of tomato and lettuce respectively. The research has developed reliable guidelines that prove the feasibility to install rooftop greenhouses in similar large Latin-American cities area.Peer ReviewedPostprint (published version
Building-integrated greenhouses raise energy co-benefits through active ventilation systems
Buildings and greenhouses consume vast amounts of energy and natural resources for heating and ventilation. It is still unclear how the synergetic effect of combining greenhouses and buildings' forced waste airflows could improve both systems' energy efficiency. This study quantified the energy recovery potential of exchanging airflows in a rooftop greenhouse (iRTG) integrated with an office building HVAC system in a Mediterranean climate. Using monitored and calibrated energy model data, the results showed that the iRTG can act as a solar collector and as a sink for a building's low-grade waste heat. The magnitude of harvested thermal energy that could be recirculated into the building by the integrated HVAC system was 205.2 kWh/m2y-1 and was limited by greenhouse low transmissivity (54%). The magnitude of building exhaust air was 198 kWh/m2y-1 at temperatures sufficient to heat and cool the iRTG. Compared to a passive ventilated configuration, the integration of active ventilation strategies doubled the energy benefits. Building ventilation requirements directly determined building and greenhouse waste flows and energy benefits, which increased by 63.1% when air changes per hour moved from 1.59 to 3.16. Overall, this demonstrates that greenhouse and building functionalities could be coupled to contribute to urban circularity and sustainability.The authors are grateful to the Secretaria d'Universitats i Recerca del Departament d'Economia i Coneixement de la Generalitat de Catalunya (Catalonia) for the award of a research scholarship (FI-DGR 2020) to Joan Muñoz-Liesa. Authors also acknowledge financial support from the Secretaria d'Universitats i Recerca del Departament de Recerca i Universitats de la Generalitat de Catalunya for the grant awarded under AGAU 2020 PANDE 00021 and the Spanish Ministry of Science, Innovation and Universities, through the “María de Maeztu” program for Units of Excellence in R&D [CEX2019-000940-M]. This work was additionally enabled by the Càtedra JG Ingenieros – Universitat Politècnica de Catalunya and the UK Engineering and Physical Sciences Research Council grant EP/P001173/1. Authors are also grateful to Elisa López-Capel, Sostenipra research group and ICTA-UAB staff for the very valuable support, advice and help.Peer ReviewedObjectius de Desenvolupament Sostenible::11 - Ciutats i Comunitats SosteniblesObjectius de Desenvolupament Sostenible::7 - Energia Assequible i No ContaminantPostprint (published version
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