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In response to the changing climate, effective building design is crucial for regulating indoor conditions while minimizing the energy consumption. This study addresses the impact of translucent fabric layers (indoor curtains) as solar protection devices, considering user-driven factors in their energy performance. We measure the indoor radiation in a residential case study in two phases: (i) a supervised phase over a day, with curtains rolled up and down by the investigators, and (ii) an unsupervised long-term phase (1.5 years) where curtains were controlled by the users. In the supervised phase, the curtains demonstrate an average filtering coefficient of 51.5%, which varies throughout the day: a minimum filtering coefficient of 40% occurs around solar noon, while raises up to 70% in the evening. In the unsupervised phase, curtains remain down for over 30% of the year, with users' choices possibly influenced by factors beyond thermal considerations. These results enhance our understanding of user interactions with movable passive systems and offer valuable insights for the design of energy-efficient buildings., Postprint (published version)

The city is a complex reality of uses that can be analyzed and represented through maps. The difficulty relies on the fact that the same piece of land in a plan view may contain different uses at different heights. This paper presents a method to graphically represent the functional complexity of cities through the colorimetric subtraction. We study the case of Barcelona, where the uses provided by the Catastro are grouped into three categories according to their rhythm: Regular, Variable and Intensive. Each group is assigned a CMY primary color (cyan, magenta, yellow). On the map, each building is represented according to the CMY color corresponding to its use, or according to the resulting color from the mixture of two or three primary colors (red, green, blue or black) if the building hosts several rhythms. The result shows that the distribution of urban rhythms is not homogeneous and varies significantly between urban areas. Intensive (31.5%) and Regular (25.9%) rhythms are the most common in Barcelona. It also makes it possible to differentiate areas of identical urban morphology (Eixample) but with very different activity and life (e.g. Passeig de Gràcia and Poblenou). This method can be applied to other cities as well, making it a useful analysis tool for urban planners, policymakers, and researchers., Postprint (published version)

The Sansalvador villa, the first project exclusively designed by Josep Maria Jujol in Barcelona, is a unique architectural complex that piques curiosity about its origins and conception. Its incomplete state, limited documentation, and blend of modernist and organic elements contribute to its exceptional nature. This article delves into its history and conceptualization by examining original documents and conducting a detailed photogrammetric survey of the built architectural complex as it is today. By overlaying new planimetry derived from fieldwork onto the original plans, certain peculiarities, discrepancies, and unforeseen changes emerge, shedding light on Jujol’s creative process. The Sansalvador villa reveals the profound connection between the project and its surroundings, showcasing Jujol’s keen awareness of the site’s pre-existing conditions. His architecture is defined by a critical approach to these conditions, integrating them as essential elements in defining the project’s character, Peer Reviewed, Postprint (published version)

In the field of urban building energy models (UBEM), the significant mismatch between simulation results and energy metered data is one of the most important barriers when using them as a planning tool. Their implementation requires a great amount of detailed building-related data, which is not always available. These data could be collected or measured for a small group of existing buildings, however such detailed data collection effort becomes impractical for large urban areas. Therefore, UBEM require certain simplifications and assumptions which can distance the input data from reality, leading to a performance gap. In this sense, knowing the influence of all the input parameters on UBEM simulation results would allow to focus the data collection efforts on the inputs with the greatest sensitivity. In this context, the aim of this research is to quantify the influence of the window-to-wall ratio (WWR) input parameter in an UBEM implemented on the residential building stock in Escaldes-Engordany (Andorra). After gathering the WWR data from a significant sample of the building stock, heating simulations of the entire building stock were carried out using the extreme WWR values, minimum and maximum, in order to analyse the variation of the results. The results obtained show an average difference of 12% between the two heating consumption simulation results. Furthermore, it can also be seen that the differences are more significant for the single-family building typology, as well as for more recently constructed buildings., Peer Reviewed, Postprint (author's final draft)

Ventilated façades can reduce heat gains through the opaque envelope of buildings, and consequently help to lower the cooling energy demand and the relative greenhouse gas emissions. However, the influence of the design features and climatic variables on their energy performance is not known enough. In this article, the influence of different parameters of the ventilated façade has been assessed. The cladding material, the relative position between mass and thermal insulation in the main wall, the air cavity geometry, and the open/closed joint configurations have been evaluated through a numerical calculation with a model that considers all these parameters, validated with experimental data. It has been observed that, in summer conditions, the best strategy to prevent heat gains is to block the energy in the outermost layers. This suggests adopting non-thermal conductor materials for claddings and the insulation of the main wall on the outer layer. Higher cavities imply a reduction of the ventilation benefits; the air remains more time in the cavity, and thus heat fluxes per unit façade area increase. On the contrary, lower air cavities allow more fresh air entrances from outside, as occurs for open joint claddings, reducing net heat gains. Additionally, widening the air cavity, up to 10 cm, results in lower average heat flux. All these different façade configurations are compared in a cradle-to-gate environmental impact assessment demonstrating that the lowest energy-demanding solution during the service life might not be the best one in the whole life cycle, thus a deeper study is needed., Peer Reviewed, Postprint (author's final draft)

On the occasion of the Universal Exhibition in Barcelona in 1929, a group of four professionals made a series of trips through Spain, between 1927 and 1928, with the aim of collecting graphic information that would serve them to carry out the project of the commission they had received: The construction of the Pueblo Español of Montjuïc. The venue was meant to be a replica of traditional Spanish architecture that would be at the service of citizens and tourists that Barcelona would receive during the event. In this research work, carried out with students from the Vallès School of Architecture (ETSAV-UPC), a fragment of that trip in which they visited Valderrobres, La Fresneda and Arnés, in the province of Teruel, is reproduced. It was in Valderrobres that they found the model that they would use as a source of inspiration for the construction of the Town Hall of the Pueblo Español, a building that presides over the Plaza. Thanks to this fieldwork based in drawings, measurements and photographs, a comparative analysis will be obtained between the original and the reproduced model, which will allow us to draw the conclusion that what really interested them was the reproduction of façade details rather than the building itself., Postprint (published version)

Traditional desert cities used a compact urban form since it provides benefits in terms of thermal comfort both in urban and interior spaces. However, many current desert cities have shifted to a sprawling model with isolated low-rise buildings, leading to longer travel distances, increased land use, inadequate public space, and higher demand for building cooling. Our study aims to investigate how vertical urban densification can reduce residential cooling demand in hot-dry regions. To achieve this, we compared single-family houses with high-rise multi-family houses in Hermosillo, Mexico. Eight case studies of real houses were selected, representing the city’s building stock, including one- and two-story single-family houses, and high-rise multi-family houses. We use dynamic energy simulations to assess the effectiveness of changing building’s shape against improving its insulation. Our results indicate that increasing vertical density leads to a reduction in the envelope-to-volume ratio, resulting in a significant decrease in cooling demand. Moving from a one-story single-family house to a high-rise multi-family house can lead to a 72% reduction in annual cooling demand. Matching the façade material properties of single-family houses and multi-family houses reduces the cooling demands of the single-family houses by 16% to 31%. However, they still have higher cooling demands compared to high-rise multi-family houses, suggesting that building form has a greater impact on cooling than thermal insulation. Our findings highlight the substantial energy savings achievable by transitioning from detached single-family houses to high-rise multi-family developments in desert cities., Funded by the European Union – NextGenerationEU, the Spanish Ministry of Science, Innovation and Universities and Recovery, Transformation and Resilience Plan, through a call from Universitat Politécnica de Catalunya (Grant Ref. 2021UPC-MS-67534). This work is also part of the project PID2020–116036RB-I00, funded by the Spanish Ministry of Science, Innovation and Universities. C.L.O. also wants to thank CONACYT-SENER for the doctoral scholarship awarded. A special thanks to the LEMA of the Department of Architecture of the University of Sonora., Peer Reviewed, Postprint (published version)

The objective of this research is to show the importance that drawing had in the gen-esis and creation of the architectural complex of the Pueblo Español in Montjuïc, built for the Universal Exposition of Barcelona in 1929. The painter Xavier Nogués and the architect Ramón Reventós were part of a team that carried out an important research work, with a clear methodology and great enthusiasm. As part of this work, a series of trips through Spain were included, which were carried out between 1927 and 1928, in order to gather information and make decisions regarding the project that would finally be carried out. Nogués and Reventós were in charge of drawing everything they saw in their travel notebooks, among other field instruments. These notebooks, which have remained hidden until today, constitute unpublished material that is analysed in this research to highlight, on the one hand, the importance they had in the final work of the Pueblo Español and in their permanence despite the ephemeral condition of the commission, and, secondly, because it is a valuable ma-terial in the recovery of the Spanish architectural-artistic heritage, especially con-cerning the one that no longer exists today., Postprint (published version)

We present unprecedented datasets of current and future projected weather files for building simulations in 15 major cities distributed across 10 climate zones worldwide. The datasets include ambient air temperature, relative humidity, atmospheric pressure, direct and diffuse solar irradiance, and wind speed at hourly resolution, which are essential climate elements needed to undertake building simulations. The datasets contain typical and extreme weather years in the EnergyPlus weather file (EPW) format and multiyear projections in comma-separated value (CSV) format for three periods: historical (2001–2020), future mid-term (2041–2060), and future long-term (2081–2100). The datasets were generated from projections of one regional climate model, which were bias-corrected using multiyear observational data for each city. The methodology used makes the datasets among the first to incorporate complex changes in the future climate for the frequency, duration, and magnitude of extreme temperatures. These datasets, created within the IEA EBC Annex 80 “Resilient Cooling for Buildings”, are ready to be used for different types of building adaptation and resilience studies to climate change and heatwaves., Peer Reviewed, Article signat per 35 autors/es, Postprint (published version)

Starting from the fortuitous encounter of a drawing made by the architect Josep Maria Jujol, as a serendipity, this writing explains, little by little, the discovery of this singular drawing, until nowuncatalogued. Even though the drawing does not allow perspective restitution through photometric methods, the object of study is observed from different points of view. Through various tests, such as the search for photographs of the time, the proportions of the parts of the drawing and various plans or aerial views, it is demonstrated that, indeed, the drawing in question is a quick sketch made by Jujol from the vicinity of the Sansalvador villa. The importance of this proof lies in the discovery of the first drawing of this project, thus initiating the process of recognition of the genius loci, as the first factor of elaboration of a project through drawing., Peer Reviewed, Postprint (published version)

Climate change and urban heat islands increase the use of mechanical cooling in buildings. The urban heat island (UHI) is responsible for a significant increase in the cooling load of buildings in Mediterranean cities. Furthermore, the use of air conditioning (AC) in buildings generates waste heat into the urban canopy thereby exacerbating the urban heat island (UHI) intensity. A significant increase in city-scale energy consumption and anthropogenic heat generation is expected due to climate change and the broader use of AC in buildings. This study investigates the combined effect of global warming and urban heat island intensity on the future building cooling demand. The analysis will be carried out using the standalone urban energy/climate model (SUECM) and future weather estimates., Peer Reviewed, Postprint (published version)

Maximizing solar energy production in Switzerland is key to meet energy transition goals. Understanding in detail the current situation, and the potential for expansion is important to develop effective strategies. With this study, we want to contribute to federal and academic efforts to measure solar energy by estimating the net energy produced by photovoltaic (PV) installations when considering their embodied energy. We calculated the values of all energy produced by PV installations across Switzerland from 1991-2021 and subtracted the embodied energy used to manufacture the PV panels and their mounting system. We considered four different types: freestanding, attached-complex, attached-simple and integrated, with progressively decreasing values of embodied energy for the supporting structure. The results show that in 2022, 50% of PV installations were producing net energy, which accounts for an accumulated historical value of 1.000 GWh, implying that 6% of the historical PV generation is net energy. If mounting systems were minimized, the accumulated net energy would reach 23%, showing the importance of integrating PV panels in building elements. These findings suggest that policies to support the diffusion of photovoltaic panels should also ensure long term use of existing installations and consider the mounting systems’ embodied energy for new ones., Peer Reviewed, Postprint (published version)

The quality of urban space is influenced by the characteristics of the environment that is close to people. What happens on the ground floors of buildings is directly related to this idea of proximity to pedestrians. In this work, the uses of the ground floor of buildings are studied to understand the quality of urban space. For this purpose, we chose 12 study areas in different parts of Barcelona. Each of them has a boundary delimited by distances of 10 minutes on foot from a reference point. For this reason, the zones do not correspond with a homogeneous morphology and do not have the same surface area. In these areas, one color was assigned to each plot corresponding to one of the four categories of ground floor use that have been previously defined: residential, food, services, and others. This information was mapped with a Geographical Information System (GIS) resulting in 12 maps that show the distribution of ground floor uses in different sectors of Barcelona. The results show that ground floor uses characterize pedestrian routes along the streets, and that this characteristic usually cannot be extrapolated to a neighborhood scale., Peer Reviewed, Postprint (author's final draft)

Indoor air quality is a crucial factor when evaluating habitability, especially in developed countries, where people spend most of their time indoors. This paper presents a novel double skin façade (DSF) system that combines physical and photocatalytic filtering strategies. The air purification system is made up of fixed slats that are both solar protection and air purification system. The objective of this work is to determine the thermal behaviour of the proposed system, so that its suitability for use in various environments may be assessed. This was carried out using a physical 1:1 scale model and a computational fluid dynamics (CFD) model. The maximum temperature inside the scale model cavity was 17–20 °C higher than outdoor air. Additionally, it was discovered that the airflow through the DSF would require forced ventilation. To determine the emissivity values of the photocatalytic coating, additional experimental measurements were made. The CFD model was tested for summer and winter conditions in Barcelona, Chicago, and Vancouver. The average increase in the intake air temperature was around 14.5 °C in winter and 12 °C in summer, finding that the system has its main use potential in temperate or cold areas with many hours of solar radiation., Peer Reviewed, Postprint (published version)

The present paper regards the proposal of an innovative low-cost ventilated load-bearing masonry using a new prefabricated dry-laid formwork wood-cement block with external interconnected holes forming a ventilated cavity. The aim of the work was to verify the performance of this solution by experimental and numerical comparison with other traditional and ventilated walls. To that end, an experimental campaign was carried out in summer on a simplified prototype involving the reproduction of the external ventilated cavity and the simultaneous measure of a ventilated cladding currently used. Numerical calculations on measure-calibrated models allowed to compare surface temperatures and heat fluxes for several ventilated and non-ventilated configurations. The results demonstrated that the proposed wall has a very high attenuation attitude on the crossing heat flows thus reducing summer gains. Moreover, the closing of the ventilation openings in winter and the use of the cavity as a still air gap also reduces the cold period dissipation. The costs are halved with respect to a traditional ventilated solution for the absence of the metal substructure., Peer Reviewed, Postprint (author's final draft)

Name of the research project : IEA Annex 80 – Resilient Cooling of Buildings Publisher: Institute of Building Research & Innovation ZT GmbH, Austria, This report summarizes an assessment of current State-of-the Art resilient cooling strategies and technologies. It is a result of a collaborative work conducted by participants members of IEA EBC Annex 80. This report consists of four chapters. In the first chapter are included relevant technologies and strategies that contribute to reducing heat loads to people and indoor environments. These technologies/strategies include Advanced window/glazing and shading technologies, Cool envelope materials, Evaporative Envelope Surfaces, Ventilated Envelope Surfaces and Heat Storage and Release. In the second chapter are assessed cooling strategies and technologies that are responsible for removing sensible heat in indoor environments: Ventilative cooling, Evaporative Cooling, Compression refrigeration, Desiccant cooling system, Ground source cooling, Night sky radiative cooling and High-temperature cooling systems. In the third chapter various typologies of cooling strategies and technologies are assessed inside the framework of enhancing personal comfort apart from space cooling. This group of strategies/technologies comprise of: Vertical-axis ceiling fans and horizontal-axis wall fans (such fixed fans differ from pure PCS in that they may be operated under imposed central control or under group or individual control), Small desktop-scale fans or stand fans, Furnitureintegrated fan jets, Devices combining fans with misting/evaporative cooling, Cooled chairs, with convective/conductive cooled heat absorbing surfaces, Cooled desktop surfaces, Workstation micro-air-conditioning units, some including phase change material storage, Radiantly cooled panels (these are currently less for PCS than for room heat load extraction), Conductive wearables, Fan-ventilated clothing ensembles, Variable clothing insulation: flexible dress codes and variable porosity fabrics. In the fourth chapter technologies and strategies pertinent to removing latent heat from indoor environments are assess, Preprint

La finca Sansalvador es el compendio de encuentros fortuitos y desencuentros que sufre este primer encargo que recibió Josep Maria Jujol en 1909. A modo de crónica, este escrito describe la serie de transformaciones acaecidas en esta obra, desde un proyecto de segunda residencia señorial, al de una fábrica de embotellamiento de agua curativa, su posterior abandono y una reciente rehabilitación. Se hace un análisis de algunos de sus elementos más significativos, que trascienden la categoría del tiempo, y recomponen fragmentos de orígenes diversos en la historia de la arquitectura, en un mismo proyecto. Este modus operandi tan característico de Jujol, permite ver que su obra se encuentra en continua transformación, partiendo de referentes del pasado y abierta a ‘objetos encontrados’ del presente., Peer Reviewed, Postprint (published version)

Climate change indicates that we are heading towards higher temperatures worldwide and greater temperature variations. To face this challenge, we need to adapt to coming conditions and minimize negative impacts on people and the environment. In this paper, we aim to generate evidence to inform decision-making when designing buildings in Switzerland by considering possible future climatic conditions and maximizing the time when buildings do not require neither heating nor cooling systems. We compare two cases, a static scenario where passive systems are permanent (wall and roof thermal insulation), and an adaptable scenario that accounts for movable passive systems (interior shutters, cross ventilation, and solar protection). The results show that the adaptable scenario returns over 1000 hours of free-running conditions more than the static case, both for 2050 and 2070. In the static scenario, the free-running period represents 25% of the year, while in the adaptable scenario it represents around 40%. Thus, passive strategies with movable devices can be a suitable approach to adapt buildings to future climate conditions, which would provide larger periods of free-running conditions, lower energy demand, and lower costs on permanent thermal insulation., Peer Reviewed, Postprint (published version)

Due to the current climate crisis, there is an urgent need to reduce greenhouse gas emissions. Improving façades’ energy performance can significantly reduce the cooling and heating demand of a building. More and more, in warm and mild climates, ventilated façade are given the function of avoiding overheating due to solar radiation and thus reducing the cooling demand of the building. However, this system’s energy performance is not easy to estimate. This study aims to assess the influence of some defining parameters of the ventilated façade on its energy performance. These parameters are not considered in the usual evaluation systems and can be relevant to the envelope’s energy performance. A calculation system has been developed so that architects can use it during the design process to know how their design decisions influence energy performance. Once validated with comparisons with measured values, the calculation system is applied to analyse the influence of some defining parameters of the façade during a warm day in Barcelona: the outer surface’s colour and the dimensions of the ventilation channel. For the studied cases, the change of these parameters implies an important variation in the daily average energy flow traversing the façade. In some cases, it even reverses the direction of the flow, changing from heat gains to heat losses. This concludes that these parameters are relevant to the energy performance of the ventilated façade and that the developed calculation system is a suitable tool to compute it., Peer Reviewed, Postprint (published version)

Aquest és el catàleg de l'exposició fragments de la finca Sansalvador: reunint per primera vegada, un recull de dibuixos i reflexions entorn a aquesta obra de Josep Maria Jujol a Barcelona, relativament desconeguda però de gran importància. Els dibuixos han estat realitzats pels estudiants de l'ETSAV a les assignatures de Representació Arquitectònica del Projecte i Derives Dibuixades., Postprint (published version)

Roller shutters are passive systems that can be operated automatically to improve building energy efficiency based on different criteria. This paper aims to compare the effect of an occupant-based and a thermal-based control of roller shutters on heating and cooling demand in an academic space. We run dynamic energy simulations of a case study in the Mediterranean climate (Barcelona, Spain). We found that the automatic control of roller shutters can significantly decrease heating and cooling demand. Both controls here analyzed perform similarly, with a rough reduction in heating of 1/2 and in cooling of 2/3. Therefore, occupant-based controls can be good alternatives that reduce energy demand as well as preserve occupants’ capacity to satisfy their needs or wills. Automated control of roller shutters could perform better if based on the energy balance of solar gains, thermal conduction and infiltration through the window. In addition to solar shading, the thermal insulation and infiltration-control provided by roller shutters are also key to improving building thermal performance in the Mediterranean climate., Peer Reviewed, Objectius de Desenvolupament Sostenible::7 - Energia Assequible i No Contaminant::7.3 - Per a 2030, duplicar la taxa mundial de millora de l’eficiència energètica, Objectius de Desenvolupament Sostenible::7 - Energia Assequible i No Contaminant, Postprint (published version)

This paper analyses the impact of urban form and vegetation on one of the most significant parameters that affect people’s thermal comfort and an indicator of urban heat vulnerability: the mean radiant temperature (MRT). To obtain spatialized results and understand in detail the current thermal situation of different public spaces that are part of the city, we combined the SOLWEIG calculation model included in the UMEP tool for QGIS with Urban Weather Generator for Rhino. Six neighbourhoods of Rome (IT) and the associated areas with typical compact urban forms, ranging from historical centre to modern suburbs, have been analysed in the warmest week of the year (August 03-09) during the most critical hours of the day (10 a.m. - 4 p.m.). Georeferenced maps with the mean values of MRT for the studied period allow us to analyse the thermal behaviour of each public square and neighbourhood and locate possible urban havens during heatwaves. This study is part of a larger work that seeks to define a more accurate approach to quantify heat vulnerability within the urban vulnerability indexes, in light of the climate crisis facing cities., Peer Reviewed, Postprint (published version)

The ventilated façade is a construction system that can prevent sunny façades from overheating. It can also be used on existing buildings as an energy rehabili-tation system, which is so necessary to make the built environment more climate resilient. The usual systems used by architects to calculate the energy performance of the architectural enclosures consider the façade in nearly steady-state conditions, with an energy balance. In addition, they disregard the particularities of the venti-lated façade. Therefore, they cannot give accurate information about the actual thermal performance of the façade. Thus, architects lack the tools to know, in a straightforward way, the real energy performance of the designed façade and how it is affected by different design decisions. The daily evolution of temperatures has been measured at different points of a ventilated façade. Also, a calculation system has been developed. It considers the defining parameters of the measured façade, the geometry of the environment, and the meteorological conditions. It can compute the ventilation of the cavity and the thermal performance, both in steady-state and transient conditions. In this presentation, the measured temperatures are compared with those re-sulting from the two types of calculation: steady-state and transient. The objective is to check which one is more appropriate in order to provide a reliable design tool for architects and designers., Peer Reviewed, Postprint (author's final draft)

This paper investigates the impact of vehicular occupation on Barcelona’s urban space and its implications for public life. The quality of urban space and its impact on residents is a key concern for public administrations. The presence of road traffic significantly influences this perception. Balancing the needs of pedestrians and ensuring access to essential services requires a careful consideration of objective data in public space policies. By categorizing the city’s surface occupation into built footprint, vehicular areas, and non-vehicular spaces, the study provides an assessment. Twelve diverse neighborhoods were selected as case studies, and a combination of fieldwork and mapping techniques was employed to analyze urban space occupation. The findings reveal spatial variations in the distribution of vehicular and non-vehicular spaces across different fabrics. By integrating numerical data and visual representations, it contributes to evidence-based decision-making in urban planning. The study emphasizes the importance of data in guiding urban policies and fostering sustainable urban environments and serves as a preliminary exploration of vehicular occupation in Barcelona's urban fabric. Ultimately, the goal is to create cities that accommodate the diverse and complex activities of the city and improve the quality of life for residents., Peer Reviewed, Postprint (published version)

The urban canyon albedo (UCA) quantifies the ability of street canyons to reflect solar radiation back to the sky. The UCA is controlled by the solar reflectance of road and façades and the street geometry. This study investigates the variability of UCA in a typical residential area of London and its impact on outdoor and indoor microclimates. The results are based on radiation measurements in real urban canyons and on a 1:10 physical model and simulations using ENVImet v 4.4.6 and EnergyPlus. Different scenarios with increased solar reflectance of roads and façades were simulated to investigate the impact on UCA and street level microclimate. The results showed that increasing the road reflectance has high absolute and relative impact on UCA in wide canyons. In deeper canyons, the absolute impact of the road reflectance is reduced while the relative impact of the walls' reflectance is increased. Results also showed that increasing surface reflectance in urban canyons has a detrimental impact on outdoor thermal comfort, due to increased interreflections between surfaces leading to higher mean radiant temperatures. Increasing the road reflectance also increases the incident diffuse radiation on adjacent buildings, producing a small increase in indoor operative temperatures. The findings were used to discuss the best design strategies to improve the urban thermal environment by using reflective materials in urban canyons without compromising outdoor thermal comfort or indoor thermal environments., Peer Reviewed, Postprint (author's final draft)

The sustainability goals agreed by most countries have made them focus their attention on the high energy consumption of buildings and the weight within this consumption of the residential sector. This makes the energy rehabilitation of existing buildings a top priority. However, energy rehabilitation is not the same in all countries. In this study, we analyse two houses in Zaragoza, one rehabilitated with an external thermal insulation system (ETICS), while the other retained its original state. Their energy behaviour was monitored and the results of each case were analysed. The results obtained from this monitoring were used to propose rehabilitation strategies in single-family social housing in Saltillo, Mexico, where the residential sector is the third-largest energy consumer. This study demonstrates the interest in analysing and using successful real cases of energy rehabilitation interventions in similar climates as a useful knowledge transfer opportunity. In addition, the importance of this "technological know-how" is highlighted to carry out a more precise energy rehabilitation., Peer Reviewed, Postprint (published version)

Preprint

This study proposes a methodology to map urban heat island intensity based on sky view factor (SVF) data, using Barcelona as a case study. We used LiDAR data to generate the SVF map of the city and empirical and simulation data to obtain the relationship between nighttime urban heat island intensity and canyon SVF in Barcelona. The data were processed and interpolated in a GIS software to obtain the micro-scale and local-scale urban heat island map of the city. The methodology proved effective in showing hot and cold spots across the city. Some unexpected results were used to discuss the validity and limitation of the urban canyon model approach for those urban fabrics with more heterogeneous morphology., Peer Reviewed, Postprint (published version)

High density and compact urban morphology are usually considered prerequisites for sustainable development. This paper explores the effect of density on the air-conditioning demand of urban grids in the Mediterranean climate, based on the case study of the Eixample of Barcelona. Representative periods in the district’s history are selected to create four urban energy models. We calculate their annual heating and cooling demands through dynamic thermal simulations in Honeybee. Results show that the denser the block, the lower the total air conditioning demand for cooling and heating. Since the energy demand of the dwellings on the top floors significantly exceeds those of intermediate floors, increased densities achieved with taller buildings allow for reducing the air-conditioning needs at the block scale., Peer Reviewed, Postprint (published version)

Postprint (published version)

The building envelope of old buildings is usually composed of a single layer with high mass and without thermal insulation, which characterizes its thermal behaviour. Retrofit actions tend to accomplish with thermal building regulations by adding a thermal insulation layer in the building envelope, but the effects of mass and thermal inertia are usually ignored. In this work, we monitored two single-family houses located next to each other for one year. They are comparable in size, composition, and orientation, but were built with one hundred years of difference. The façade of the old house (House 1) has a single layer of stone. The newer house (House 2) has a multi-layer façade with thermal insulation. The annual results of temperature have not presented significant differences. But, in the winter and summer week, under free-running operation, House 1 presented less temperature fluctuation compared with House 2. In winter, the mean temperature was similar, but in summer House 1 remained cooler than House 2. These results indicate that the effects of mass in the thermal behaviour of old buildings should be considered before undertaking retrofit actions and the addition of a thermal insulation layer., Peer Reviewed, Postprint (published version)

This paper contributes to studies with a global view of buildings environmental impact, considering the main stages of the building life cycle. The objective is to determine the energy trade-off between the operational improvement gained with a passive strategy and the embodied energy associated to it. The evaluation contemplates a hypothetical case study situated in Barcelona subjected to a Mediterranean climate. Three versions of the same south oriented dwelling are outlined according to local regulations. Two versions consider a passive architectural solution, a balcony as a solar shade and a glazed gallery performing as a greenhouse. Both elements control the energy demand for interior conditioning (cooling and heating). Calculations compare the energy reduction in the operational stage with the embodied energy and emissions data related to construction materials for a 50-year period. Results show that sometimes, when energy and emissions from operational and embodied stage are accounted, the passive strategy can be counterproductive. So, attention must be paid on the election of passive solutions and their environmental impact, specially once they are declared as part of energy efficiency strategies. Only global calculations, considering the different stages in a building life cycle, can demonstrate the energy efficiency., Peer Reviewed, Postprint (published version)

Postprint (published version)

Fishing has always been a basic activity in different societies, being one of the most dangerous jobs. Facing the problem of the high number of accidents and casualties in the Spanish fishing sector, we present an observational study and statistical analysis from reports of the maritime accidents that happened from 2000 to 2020. The reports of the accidents had been published by the Spanish Marine Accident and Incident Investigation Standing Commission, CIAIM. The research has been done in order to understand the causes and factors that have conducted to the accidents, trying to suggest and publish, from those causes, some recommendations to reduce or even avoid them. Up to 2020, it seems that some “Peltzman effect” is in place, as the number of accidents does not decrease even with the measures taken. Some conclusions and indications for maritime policy are suggested in this study, Postprint (published version)

In cold regions, the reduction in envelope thermal transmittance is often the dominant parameter in ensuring thermal comfort in buildings. However, countries in warmer climates have also adopted this same strategy, often neglecting other parameters that are more influential in their respective climate regions that can achieve thermal comfort. This study focuses on passive building strategies to ensure a building’s thermal comfort conditions in Mediterranean climates in the winter. This monitoring study compares two dwellings during the winter in Barcelona, Spain, in order to analyze the impact of not only the envelope’s thermal properties on indoor temperature, but also the role of other factors such as outdoor temperature and solar gains. The dwellings were built in different decades, each following distinct building technical codes, diverse construction techniques, and building materials. The methodology used in this study is based on thermal measurements, meteorological data, and spreadsheet calculations. Comparing these results with the recent updates in Spain’s technical code and other studies, the investigation demonstrates that to achieve a suitable indoor thermal temperature in a passive way, especially in Mediterranean climates, incorporating other factors such as the combination of thermal inertia and solar gains can be more effective than a strategy mainly focused on reducing thermal transmittance. This analysis demonstrates that a building’s thermal performance does not mainly depend on envelope thermal transmittance, but rather a complex system involving a set of variables such as thermal inertia as well as solar gains, based on parameters such as building orientation and urban context., Peer Reviewed, Objectius de Desenvolupament Sostenible::7 - Energia Assequible i No Contaminant, Objectius de Desenvolupament Sostenible::11 - Ciutats i Comunitats Sostenibles, Objectius de Desenvolupament Sostenible::12 - Producció i Consum Responsables, Postprint (published version)

Globally, the building industry has grown in the last decades. Furthermore, the new technological advances in construction materials with high embodied energy have been widely introduced in Latin American countries’ architecture. Over the last decades, the Ecuadorian Andean region has experienced these changes. To analyze the environmental impact of these construction transformations, this research quantifies the Specific Total Embodied Energy (STEE) of 40 houses built between 1980 and 2020. Additionally, this research addresses the Specific Total Weight (STW) of the study cases. The calculations of these two parameters consider three components: Structure, Envelope, and Finishes; however, these calculations disregard technical installations. This methodology was applied in Cuenca-Ecuador, where the results show that the STEE of the entire building has experienced an increase of 2.19 times in the last four decades. The component with the highest STEE and STW is the Structure, whereas the least representative is the Finishes, but it has the highest increase tendency. Despite the STEE Envelope component having had significant growth over the last decades, its STW has shown a decreasing tendency that can have thermal repercussions in interior conditions. Finally, these results can be used as architectural and construction guidelines in this region to reduce the energy impact of buildings from the design phase., Postprint (published version)

Building archetypes development has been the focus of numerous research works over the past decades and are considered one of the biggest challenges, as well as one of the main sources of inaccuracies in Urban Buildings Energy Models (UBEM). The development of machine learning and data mining techniques, such as clustering, as well as the access to building data at disaggregated scales, has opened new horizons in this field. With the aim to reduce additional simulation errors derived from the fragmentation process of the archetype approach in UBEMs, this paper presents an alternative hybrid approach to identify representative building archetypes combining the classic deterministic and a data-driven clustering approach using building data at both building and cadastral unit scales. The methodology was tested in the Escaldes-Engordany building stock, a city of the Principality of Andorra, and the resulting archetypes have been compared with the archetypes obtained by the application of both approaches applied separately. A total of 71 archetypes were identified in the Escaldes-Engordany building stock. The results show that both approaches complement each other and allow to overcome the identified barriers when applied separately. In addition, the results also reveal that there is an important heterogeneity of certain building aspects not only between buildings, but also within buildings, which cannot be detected if the fragmentation is still carried out at the building scale., Peer Reviewed, Objectius de Desenvolupament Sostenible::11 - Ciutats i Comunitats Sostenibles, Objectius de Desenvolupament Sostenible::7 - Energia Assequible i No Contaminant, Postprint (author's final draft)

Aquest llibre és el primer recull de l'experiència docent feta per l'equip de professors del departament de Representació Arquitectònica a l'Escola Tècnica Superior del Vallès. Es mostren alguns treballs d'estudiants o enunciats d'exercicis que permeten donar una visió global de la formació en matèries gràfiques impartides a l'ETSAV., Postprint (published version)

A central question for urban sustainability is how to build cities that minimize, at the same time, the use of land and energy consumption. Future cities should be as dense as possible to meet the first requirement. However, the energy performance of dense urban areas is still under debate due to the lack of sound arguments. Since the origins of urbanism in the XIXth century, urban planners have incorporated energy considerations into their designs in a qualitative way. Nowadays, the discipline of Urban Physics is a well-established field able to provide them also with quantitative energy information to aid decision-making. This chapter explores how the current energy simulation capabilities, particularly the Finite Elements Methods, can contribute to a systemic study of energy exchanges in dense urban environments. We focus on radiative energy exchanges, which are especially challenging in dense urban morphologies. Finally, we discuss how the feedback between urban thermography and simulations can improve our understanding of the thermal behaviour of real urban environments., Peer Reviewed, Postprint (published version)

The data contained in this article refers to the measurements of climatic factors during an entire year in low latitudes regions with warm and humid climates, in Santa Rosa city from Ecuador. Since the geographical location and the importance of cloudiness in these regions, these measurements have focused on the solar radiation flux, cloud cover and sky temperature. The data obtained have been configured in a weather file for energy calculations, which has been used in the research article “Assessment of the reflectivity and emissivity impact on light metal roofs thermal behaviour, in warm and humid climate”., Peer Reviewed, Postprint (published version)

While performing building energy simulations, weather data are among the most important pieces of information needed by models and tools. In urban conditions, the typical rural weather files should be modified to take into account the microclimatic effects in urban areas. This chapter presents an overview of the most relevant effects to be considered: shadows, long-wave exchange, urban heat island, urban ventilation patterns, and urban greening, presenting a modelling chain procedure developed by the authors and to be used in TRNSYS tool, as well as the result of simulations done for the cases of Rome (Italy) and Antofagasta (Chile)., Peer Reviewed, Postprint (published version)

All buildings, even the most passive, need active energy to provide habitability. Apart from heating and cooling needs, which have been broadly studied and regulated, a significant percentage of the energy consumed in housing is due to home appliances. Furthermore, this value is increasing as the design of environmental conditioning becomes more efficient. The objective of this paper is to visualize the impact of these consumptions by a graphical equivalence that uses drawing to represent the surface area of photovoltaic modules that correspond to the energy demand. With this aim, a straightforward method is proposed based on graphical means that fit well with the working practice of architects. The procedure starts by detailing the energy consumption of a home, focusing on the consumption values of all appliances and lighting. Next, each single value is converted into the surface area of photovoltaic modules required to produce this energy in one year. Finally, each appliance and its corresponding energy production area are represented graphically side by side, resulting in the housing energy equivalence. This method has been tested by a group of architecture master's students using their own homes as the case study. The results show that the energy equivalent surface area for lighting and appliances represents between 8% and 46% of the floor area of their homes. Altogether, this approach makes visible a pending question in sustainable building design - the consumption of electrical home appliances - and provides rough graphical data which is useful for pre-dimensioning in the architectural design process., Peer Reviewed, Postprint (published version)

The increasing urbanisation trend of the last 50 years has drastically changed the landscape worldwide. The majority of world population is now living in cities and urban population growth is still accelerating, especially in developing countries. This chapter introduces the key concepts discussed in this book—i.e. urban heat island, urban climate and urban metabolism—and provides an overview of all the contributions. The fundamental issue discussed in the introduction and throughout the book is the need to overcome current fragmentation between disciplines and knowledge on cities. A new integrated urban science could effectively support the transition of existing cities toward more sustainable environments and also change our way to envision future cities. In this context, even though predicting the future is not possible, urban energy modelling and simulation could be valuable tools to guide the design and planning of future urban environments., Peer Reviewed, Postprint (published version)

This chapter presents the urban microclimate impact on comfort and energy demand by buildings located in high-latitude temperate regions, characterised by higher heating demand compared to cooling. It focusses on London as a case study of such a location and presents results from measurements and computational studies during the last 20 years. The relationship of surface and air UHI in high-latitude cities is first described as well as the relationship between UHI and building energy demand; results from London are used to illustrate the impact. It follows a description of urban albedo outlining contributing parameters. Modelling tools enabling the study of microclimate impact on indoor thermal conditions are then described. Recent results of a study of urban albedo in London and the application of modelling tools are presented., Peer Reviewed, Postprint (published version)

The global effects of climate change will increase the frequency and intensity of extreme events such as heatwaves and power outages, which have consequences for buildings and their cooling systems. Buildings and their cooling systems should be designed and operated to be resilient under such events to protect occupants from potentially dangerous indoor thermal conditions. This study performed a critical review on the state-of-the-art of cooling strategies, with special attention to their performance under heatwaves and power outages. We proposed a definition of resilient cooling and described four criteria for resilience—absorptive capacity, adaptive capacity, restorative capacity, and recovery speed —and used them to qualitatively evaluate the resilience of each strategy. The literature review and qualitative analyses show that to attain resilient cooling, the four resilience criteria should be considered in the design phase of a building or during the planning of retrofits. The building and relevant cooling system characteristics should be considered simultaneously to withstand extreme events. A combination of strategies with different resilience capacities, such as a passive envelope strategy coupled with a low-energy space-cooling solution, may be needed to obtain resilient cooling. Finally, a further direction for a quantitative assessment approach has been pointed out., Peer Reviewed, Postprint (author's final draft)

The KM3NeT research infrastructure in the Mediterranean is a multi-purpose cubic-kilometre neutrino observatory consisting of two detectors optimised to study cosmic and atmospheric neutrinos between GeV to PeV energies. Additionally, KM3NeT multi-photomultiplier optical modules allow the detection of interaction products from neutrinos with energies of a few MeV by selecting nanosecond coincidences within the photomultipliers of the same module. The distribution of the number of photomultipliers forming a coincidence (multiplicity) for the duration of the supernova emission is used as a proxy of the average neutrino energy. Using an optimised coincidence selection the KM3NeT detectors will be sensitive to supernovae in our Galaxy and beyond. A high number of detected events from a core collapse supernova explosion is expected in KM3NeT thanks to its large effective volume. The measurement of the neutrino light curve properties, such as the light curve start time and the presence of the standing accretion shock instability oscillations is possible with such statistics. Sub-millisecond time synchronisation between KM3NeT detectors allows joint observation. Such a scheme can be also a viable solution to synchronise the KM3NeT telescopes with other detectors aiming to observe neutrino emission from core collapse supernovae through the SNEWS network. © Copyright owned by the author(s)., Article signat per 297 autors/es: M.Ageron, S. Aiello, A. Albert, M. Alshamsi, S. Alves Garre, Z. Aly, A. Ambrosone, F. Ameli, M. Andre, G. Androulakis, M. Anghinolfi, M. Anguita, G. Anton, M. Ardid, S. Ardid, W. Assal, J. Aublin, C. Bagatelas, B. Baret, S. Basegmez du Pree, M. Bendahman, F. Benfenati, E. Berbee, A. M. van den Berg, V. Bertin, S. Beurthey, V. van Beveren, S. Biagi, M. Billault, M. Bissinger, M. Boettcher, M. Bou Cabo, J. Boumaaza, M. Bouta, C. Boutonnet, G. Bouvet, M. Bouwhuis, C. Bozza, H.Brânzas, R. Bruijn, J. Brunner, R. Bruno, E. Buis, R. Buompane, J. Busto, B. Caiffi, L. Caillat, D. Calvo, S. Campion, A. Capone, H. Carduner, V. Carretero, P. Castaldi, S. Celli;, R. Cereseto, M. Chabab, C. Champion, N. Chau, A. Chen, S. Cherubini, V. Chiarella, T. Chiarusi, M. Circella, R. Cocimano, J. A. B. Coelho, A. Coleiro, M. Colomer Molla, S. Colonges, R. Coniglione, A. Cosquer, P. Coyle, M. Cresta, A. Creuso, A. Cruz, G. Cuttone, A. D’Amico, R. Dallier, B. De Martino, M. De Palma, I. Di Palma, A. F. Díaz, D. Diego- Tortosa, C. Distefano, A. Domi, C. Donzaud, D. Dornic, M. Dörr, D. Drouhin, T. Eberl, A. Eddyamoui, T. van Eeden, D. van Eijk, I. El Bojaddaini, H. Eljarrari, D. Elsaesser, A. Enzenhöfer, V. Espinosa, P. Fermani, G. Ferrara, M. D. Filipovic, F. Filippini, J. Fransen, L. A. Fusco, D. Gajanana, T. Gal, J. García Méndez, A. Garcia Soto, E. Garçon, F. Garufi, C. Gatius, N. Geißelbrecht, L. Gialanella, E. Giorgio, S. R. Gozzini, R. Gracia, K. Graf, G. Grella, D. Guderian, C. Guidi, B. Guillon, M. Gutiérrez, J. Haefner, S. Hallmann, H. Hamdaoui, H. van Haren, A. Heijboer, A. Hekalo, L. Hennig, S. Henry, J. J. Hernández-Rey, J. Hofestädt, F. Huang,W. Idrissi Ibnsalih, A. Ilioni, G. Illuminati, C.W. James, D. Janezashvili, P. Jansweijer, M. de Jong, P. de Jong, B. J. Jung, M. Kadler, P. Kalaczynski, O. Kalekin,U. F. Katz, F. Kayzel, P.Keller, N. R. Khan Chowdhury, G. Kistauri, F. van der Knaap, P. Kooijman, A. Kouchner, M. Kreter, V. Kulikovskiy, M. La, Postprint (published version)

The study focused on low light intensity spaces. The research helps to find strategies for the reduction of energy consumption. It aims to highlight the role of colour temperature in the lighting design of historic buildings. The case study corresponds to a Roman archaeological site of the Badalona Museum in Barcelona. The lighting design uses three different colour temperatures to differentiate groups of surfaces which play a different role in the visual field. The information panels are lit with white light, the old Roman city has warm white colour light, and the new walkway over the ruins is lit with cool white light. This study evaluates colour temperature value, luminance value and visual task. The present work reveals that the colour temperature allows setting apart and classifying the visual information from low luminance values. The research presented addresses the importance of the colour temperature, as a significant visual perception component, in the inherent low light intensity design proposal to energy conservation., Peer Reviewed, Postprint (author's final draft)

Finite element methods for heat simulation at urban scale require mesh-volume models, where the meshing process requires a special attention in order to satisfy FEM requirements. In this paper we propose a procedural volume modeling approach for automatic creation of mesh-volume buildings, which are suitable for FEM simulations at urban scale. We develop a basic rule-set library and a building generation procedure that guarantee conforming meshes. In this way, urban models can be easily built for energy analysis. Our test-case shows a street created with building prototypes that fulfill all the requirements for being loaded in a FEM numerical platform such as Cast3M (www-cast3m.cea.fr)., Postprint (published version)

Renewable energy polygeneration systems are a viable alternative to fossil-fuel based systems, but storage solutions may be necessary when aiming for high sustainability and autonomy. As each storage technology has different strengths and weaknesses, combinations of various storage solutions may lead to better techno-economic performance than singular approaches. To this purpose, an optimization model including a novel dispatch control strategy for a hybrid energy storage system (HESS) is proposed, which uses biogas for long-term and batteries for short-term storage. The model optimizes for minimum lifetime costs while exploiting the biomass resources with maximum efficiency and quantifying the additional solar and battery capacities needed. It is applied in a case study with an innovative biomass-based polygeneration system in a rural locality of Bolivia to serve electricity, potable water, and bio-slurry as fertilizer. The results indicate that even with maximized efficiency of the biomass resource conversion, large PV and battery capacities are necessary to satisfy the electricity demand of the locality. Despite of the high investment costs, the biomass-based polygeneration system would cost 22% less over the project lifetime than the fossil-fuel based reference system while being less dependent on fuel price changes. It would also reduce CO2-emissions by over 98%., This research has been conducted in collaboration between UPC (Universitat Politècnica de Catalunya) and KTH Royal Institute of Technology, funded through Erasmus Mundus Joint Doctoral Programme SELECT+, the support of which is gratefully acknowledged. The project STandUP for Energy provided resources for supervision of this study. AI acknowledges support from Spanish project MOET_BIA2016-77675-R., Peer Reviewed, Postprint (published version)

Many methods to generate future weather files to run building performance simulations have been proposed. However, future weather files do not account for local urban climate modifications, such as urban heat island and may not be representative of urban buildings’ climate conditions. This study describes a methodology to include urban effects in future weather files using multiple tools: the EURO-CORDEX regional climate model data, Urban Weather Generator, the URBVENT canyon wind models and EnergyPlus. Residential buildings located in different areas of London are used to test the methodology. The results confirm the significant impact of urban context on future-urban climate conditions and urban building thermal response., Peer Reviewed, Postprint (published version)