Rethinking User Behaviour Comfort Patterns in the South of Spain—What Users Really Do

Although energy analysis techniques can contribute to substantial energy savings in housing stock retrofitting operations, the outcomes often deviate significantly from the predicted results, which tend to overestimate potential savings by overestimating the starting energy baselines, particularly in southern Europe. This deviation can be largely attributed to occupant practice relating to the use of air conditioning facilities and the temperatures at which occupants feel comfortable. The patterns observed differed widely from standard values. In this study environmental variables, primarily indoor air temperature both with and without HVAC, were monitored in occupied dwellings for a full year. The data gathered were supplemented with surveys on occupants’ temperature-related behaviour to define comfort patterns. The findings show that the standards in place are not consistent with actual comfort-accepted patterns in medium- to low-income housing in southern Spain, where energy consumption was observed to be lower than expected, mostly because occupants endure unsuitable, even unhealthy, conditions over long periods of time. A new user profile, better adjusted to practice in southern Europe, particularly in social housing, is proposed to reflect the current situation

Thermal Perception in Mild Climate: Adaptive Thermal Models for Schools

A comprehensive assessment of indoor environmental conditions is performed on a representative sample of classrooms in schools across southern Spain (Mediterranean climate) to evaluate the thermal comfort level, thermal perception and preference, and the relationship with HVAC systems, with a comparison of seasons and personal clothing. Almost fifty classrooms were studied and around one thousand pool-surveys distributed among their occupants, aged 12 to 17. These measurements were performed during spring, autumn, and winter, considered the most representative periods of use for schools. A new proposed protocol has been developed for the collection and subsequent analysis of data, applying thermal comfort indicators and using the most frequent predictive models, rational (RTC) and adaptive (ATC), for comparison. Cooling is not provided in any of the rooms and natural ventilation is found in most of the spaces during midseasons. Despite the existence of a general heating service in almost all classrooms in the cold period, the use of mechanical ventilation is limited. Heating did not usually provide standard set-point temperatures. However, this did not lead to widespread complaints, as occupants perceive the thermal environment as neutral—varying greatly between users—and show a preference for slightly colder environments. Comparison of these thermal comfort votes and the thermal comfort indicators used showed a better fit of thermal preference over thermal sensation and more reliable results when using regional ATC indicators than the ASHRAE adaptive model. This highlights the significance of inhabitants’ actual thermal perception. These findings provide useful insight for a more accurate design of this type of building, as well as a suitable tool for the improvement of existing spaces, improving the conditions for both comfort and wellbeing in these spaces, as well as providing a better fit of energy use for actual comfort conditions

Protocols for measuring the airtightness of multi-dwelling units in Southern Europe

The airtightness of building envelopes is one of the factors which most affects the hygrothermal conditions and the air quality of the indoor environment, as well as the energy consumption of the building. In multi-dwelling units this contributes significantly to the overall load for heating or air conditioning, making it possible to calculate the repercussion of infiltrations on the energy demand of a dwelling as between 20 to 50% of the total amount, depending on the climate zone and construction characteristics of the envelope. Hence the importance of knowing the parameters that characterise it. Pressurisation/depressurisation tests are the best method for characterisig these, but must be carried out in accordance with specific measurement procedures. The main objective of this paper is the proposal of five specific protocols for carrying out these tests in MDU, and their specific use in buildings in Southern European regions. In order to develop and validate this proposal we have carried out a series of multi test in ten dwelling units in a block recently built in the south of Spain. The results of these tests are presented and analysed here. These confirm the need for some protocols to distinguish between wet and dry spaces within the dwelling, given the difference in airtightness between them, and to expand the study indicators proposed by international regulations for a more accurate rendering of the behaviour of the envelope and the elements within it

CO2 Concentration and Occupants’ Symptoms in Naturally Ventilated Schools in Mediterranean Climate

A large part of the school building stock in Andalusia lacks ventilation facilities, so that the air renewal of the classrooms is achieved through the building envelope (air infiltration) or the opening of windows. This research analyses the airtightness of the classrooms in Andalusia and the evolution of CO2 concentration during school hours through in situ monitoring. Pressurization and depressurization tests were performed in 42 classrooms and CO2 concentration was measured in two di erent periods, winter and midseason, to study the impact of the di erent levels of aperture of windows. About 917 students (11–17 years of age) were surveyed on symptoms and e ects on their health. The mean n50 values are about 7 h-1, whereas the average CO2 concentration values are about 1878 ppm, with 42% of the case studies displaying concentrations above 2000 ppm with windows closed

Predictive models for airtightness in social housing in a Mediterranean region

This article describes two models developed to predict airtightness in multifamily buildings in a Mediterranean region. They are designed to enable city planners, architects and engineers to estimate airtightness in homes built from 1980 to date (predictive model 1) or prior to 1979 (predictive model 2), when the first domestic energy conservation regulations entered into effect. They are based on a series of readily accessible parameters such as winter severity, envelope exposure, presence of a bathroom window and façade type. The estimated n50 data can be used with energy certification software, which presently envisages the same, non-experimentally quantified mean value for all types of housing. They can also be entered into energy and comfort simulation programs to predict energy consumption and expected indoor temperatures

Application of integrated building simulation and CFD to a classroom heating case study in a mediterranean climate

This study develops knowledge of the methodological analysis of indoor air distribution in high density rooms, allowing evaluation of the expected comfort level of the occupants. A typical classroom is presented as a case study, focusing on the influence of dedicated ventilation. The methodology established the boundary conditions using discretization and determination of values over time which defined the dynamic energy behaviour of the room, by means of a nodal model. The study incorporates sectional isothermal curves and air velocity analysis, the use of indicators to evaluate the thermal comfort of the occupants according to ASHRAE standards, and comparisons of alternative HVAC systems. A case study application shows poor efficiency of traditional radiator heating systems versus those which incorporate a neutral ventilation air supply

Modelos predictivos del consumo energético de climatización asociado a soluciones de fachadas en Madrid a partir de la monitorización en módulos de ensayo

This study aims to narrow the gap between predicted and actual energy performance in buildings. Predictive models were established that relate the electric consumption by HVAC systems to maintain certain indoor environmental conditions in variable weather to the type of façade. The models were developed using data gathered from test cells with adiabatic envelopes on all but the façade to be tested. Three façade types were studied. The first, the standard solution, consisted in a double wythe brick wall with an intermediate air space, the configuration most commonly deployed in multi-family dwellings built in Spain between 1940 and 1980 (prior to the enactment of the first building codes that limited overall energy demand in buildings). The other two were retrofits frequently found in such buildings: ventilated façades and ETICS (external thermal insulation composite systems). Two predictive models were designed for each type of façade, one for summer and the other for winter. The linear regression equations and the main statistical parameters are reported.Este trabajo pretende realizar aportaciones de interés para reducir la brecha existente entre el comportamiento energético real y previsto en edificios. Tiene como principal objetivo establecer modelos predictivos que relacionen el consumo eléctrico de climatización para mantener unas determinadas condiciones operacionales en el ambiente interior, según sea el clima exterior, en función de la solución de fachada. Esos modelos predictivos se obtienen para módulos de ensayo en la que toda su envolvente es adiabática, a excepción de la fachada que se quiere ensayar. Tres soluciones de fachada han sido consideradas: una base que se corresponde con una solución de doble hoja de ladrillo con cámara de aire intermedia, la solución más común en viviendas plurifamiliares en España que fueron construidos entre 1940 y 1980, previamente a la primera normativa que, con carácter global, limitaba la demanda energética en los edificios; y dos soluciones de rehabilitación de la fachada anterior muy frecuentemente utilizadas: Fachada Ventilada y ETICS. Usando los datos de monitorización de los consumos eléctricos de equipos de climatización en esos tres módulos, se generan esos modelos predictivos, tanto para el periodo de verano como el de invierno, que son rectas de regresión lineal cuyas ecuaciones se enuncian, así como sus principales parámetros estadístico

Airtightness and indoor air quality in subsidised housing in Spain

Over three million subsidised dwellings were built in Spain between 1940 and 1980. Most of these buildings are now obsolete and fail to comply with thermal comfort and ventilation standards. A building's existing energy performance, including its airtightness, should be determined prior to conducting low-energy refurbishment, for those factors, particularly the latter, impact thermal comfort, energy demand and indoor air quality (IAQ) fairly heavily. This paper introduces a study on airtightness and IAQ in subsidised housing built in Spain in the aforementioned 40-year period. Airtightness and CO2 measurements taken in 2014-2015 in six units in multi-dwelling buildings, three each in Seville and Madrid, are described. The results show that in a building in Madrid, the number of air changes per hour at a pressure of 50 Pa (n50) ranges from 3.2 to 8.3. The winter time CO2 concentration in bedrooms is 1900 ppm and in living rooms 1400 ppm, with peaks of 5000 ppm and 4700 ppm, respectively. The number of air changes per hour at 50 Pa (n50) in Seville, ranges from 5.0 to 9.5. The winter time CO2 concentration in bedrooms is 1500 ppm and in living rooms 800 ppm, with peaks of 6000ppm and 4000 ppm, respectively. In the summer, however, when users tend to open windows at night primarily to let in cooler air, the CO2 concentration values observed in Seville drop to 700 ppm and in Madrid to 1100 ppm. As those values are much higher than recommended in the standards on good indoor air quality, the inference is that winter time housing ventilation must not be allowed to rest solely on users’ voluntary opening of windows

Deletion of the von Hippel-Lindau gene causes sympathoadrenal cell death and impairs chemoreceptor-mediated adaptation to hypoxia

Mutations of the von Hippel–Lindau (VHL) gene are associated with pheochromocytomas and paragangliomas, but the role of VHL in sympathoadrenal homeostasis is unknown. We generated mice lacking Vhl in catecholaminergic cells. They exhibited atrophy of the carotid body (CB), adrenal medulla, and sympathetic ganglia. Vhl‐null animals had an increased number of adult CB stem cells, although the survival of newly generated neuron‐like glomus cells was severely compromised. The effects of Vhl deficiency were neither prevented by pharmacological inhibition of prolyl hydroxylases or selective genetic down‐regulation of prolyl hydroxylase‐3, nor phenocopied by hypoxia inducible factor overexpression. Vhl‐deficient animals appeared normal in normoxia but survived for only a few days in hypoxia, presenting with pronounced erythrocytosis, pulmonary edema, and right cardiac hypertrophy. Therefore, in the normal sympathoadrenal setting, Vhl deletion does not give rise to tumors but impairs development and plasticity of the peripheral O2‐sensing system required for survival in hypoxic conditions

Olfaction in eating disorders and abnormal eating behavior: a systematic review

The study provides a systematic review that explores the current literature on olfactory capacity in abnormal eating behavior. The objective is to present a basis for discussion on whether research in olfaction in eating disorders may offer additional insight with regard to the complex etiopathology of eating disorders (ED) and abnormal eating behaviors. Electronic databases (Medline, PsycINFO, PubMed, Science Direct, and Web of Science) were searched using the components in relation to olfaction and combining them with the components related to abnormal eating behavior. Out of 1352 articles, titles were first excluded by title (n = 64) and then by abstract and fulltext resulting in a final selection of 14 articles (820 patients and 385 control participants) for this review. The highest number of existing literature on olfaction in ED were carried out with AN patients (78.6%) followed by BN patients (35.7%) and obese individuals (14.3%). Most studies were only conducted on females. The general findings support that olfaction is altered in AN and in obesity and indicates toward there being little to no difference in olfactory capacity between BN patients and the general population. Due to the limited number of studies and heterogeneity this review stresses on the importance of more research on olfaction and abnormal eating behavior