On the energy performance of the Mediterranean school building stock: the case of the Apulia Region

The refurbishment opportunities provided by climate policies require an adequate knowledge of the school building stock, characterised by an urgent need of maintenance. Nevertheless, empirical evidence on energy performance of school samples appears limited due to the difficulty in retrieving data, although field data analysis is crucial in the built environment management. This study aims to explore existing energy conditions of an educational building sample hosting pre-schools, primary and lower secondary schools, located in southern Italy (Apulia Region). Firstly, an overview of the schools based on data retrieved from the regional dataset was performed. Then, more than 1000 buildings were clustered based on two predictors (construction year and surface-to-volume ratio), identifying five clusters representing the majority Apulian schools. In addition, billed gas and electricity data collected for 47 schools over a five-year period (2017-2021) were analysed, identifying annual and monthly trends, benchmarks, and mean values, which account for 46.5 (gas consumption), 15.59 kWh/m2 (electricity consumption). On average, source total consumption in 2020 experienced a reduction of 20%, partly due to Covid-19 restrictive measures. Finally, factors affecting heating consumptions were explored, and a regression analysis was performed, identifying heating degree days, construction year and boiler power to be the most significant.

Network for the continuous monitorization of environmental quality in educational buildings

In this article we present a measurement network designed to improve air quality and energy efficiency in educational centers. We have made prototypes with carbon dioxide, temperature, humidity and light sensors with network connection for remote storage and processing of data, as well as autonomous prototypes. The design and construction of the equipment has been accelerated by taking advantage of previous experiences and has been carried out by the electronics teachers and students of the IES Escolas Proval de Nigran (Spain) within the framework of an Innovation Project granted by the Xunta de Galicia. The IES Val Miñor of Nigran also participates in the project in the development and interpretation of data, and the company Hermes Smart Control acts as a technology transfer center and has made a commercial product. The project has already been extended to other educational centers, taking measurements that demonstrate its usefulness for the application of ventilation regulations during the COVID-19 pandemic and are planned future uses such as automatic ventilation control or the improvement of energy efficiency in the educational buildings. © 2022 IEEE.

Predicting Electricity Consumption in Microgrid-based Educational Building using Google Trends, Google Mobility, and COVID-19 Data in the Context of COVID-19 Pandemic

Electricity demand has been disrupted in various countries since many governments imposed comprehensive social restriction policies to control the COVID-19 pandemic. Obtaining accurate electricity consumption predictions in this highly uncertain period is particularly important for building operators to improve the corresponding operational planning efficacy. Nevertheless, developing accurate electricity consumption prediction models for buildings within the COVID-19 context is a nontrivial task. Correspondingly, this research focuses on incorporating publicly available internet data (i.e., Google Trends, Google Mobility, and COVID-19 data) to develop accurate electricity consumption prediction models for microgrid-based buildings during the COVID 19 pandemic. For this purpose, we developed extreme gradient boosting (XGBoost), support vector regression (SVR), and autoregressive integrated moving average with explanatory variable (ARIMAX) models. As a case study, we analyzed a real-life electricity consumption dataset of a six-floor microgrid-designed educational building at a technological university in Bandung, West Java, Indonesia. The findings show that incorporating publicly online data positively impacts prediction accuracy. The accuracy increases, even more when we use the lagged value of the predictors. XGBoost models utilizing lagged historical values of the electricity consumption, Google Trends, and COVID-19 data of the previous days is the best performing model. However, adding more lagged predictors does not necessarily increase SVR models’accuracy. Lastly, the ARIMAX models become the worst-performing models compared to XGBoost and SVR models. Author

Indoor air quality evaluation in naturally cross-ventilated buildings for education using age of air

Natural ventilation (NV) is a strategy of bioclimatic design to promote hygrothermal comfort and indoor air quality (IAQ). Nowadays, COVID-19 pandemic highlights the review of ventilation standards. In Mexico, the IAQ standard states a minimum of 6 ACH for educational buildings. ACH considers NV as an ideal piston flow and does not provide information of indoor airflow distribution. In this work, new age of air associated parameters are proposed, considering the indoor airflow distribution: the air renovation per hour (ARH) and the renovation parameter R. An isolated educational building located in a rural region is studied. Four window configurations of cross-ventilation are considered. All configurations have one windward window located at bottom. The configurations axial and upward have one leeward window at bottom and top, respectively. While, configurations corner and upward corner have one lateral side window at bottom and top, respectively. A CFD model of the educational building is validated with experiments. The axial configuration has the best performance according to ACH, nevertheless has the worst performance according to ARH and R. The results show that NV evaluation using ACH can lead to wrong decisions. An improvement of NV standard with the age of air associated parameters is recommended. © 2021 Institute of Physics Publishing. All rights reserved.

Towards a Living Lab for Enhanced Thermal Comfort and Air Quality: Analyses of Standard Occupancy, Weather Extremes, and COVID-19 Pandemic

Maintaining indoor environmental (IEQ) quality is a key priority in educational buildings. However, most studies rely on outdoor measurements or evaluate limited spatial coverage and time periods that focus on standard occupancy and environmental conditions which makes it hard to establish causality and resilience limits. To address this, a fine-grained, low-cost, multi-parameter IOT sensor network was deployed to fully depict the spatial heterogeneity and temporal variability of environmental quality in an educational building in Sydney. The building was particularly selected as it represents a multi-use university facility that relies on passive ventilation strategies, and therefore suitable for establishing a living lab for integrating innovative IoT sensing technologies. IEQ analyses focused on 15 months of measurements, spanning standard occupancy of the building as well as the Black Summer bushfires in 2019, and the COVID-19 lockdown. The role of room characteristics, room use, season, weather extremes, and occupancy levels were disclosed via statistical analysis including mutual information analysis of linear and non-linear correlations and used to generate site-specific re-design guidelines. Overall, we found that 1) passive ventilation systems based on manual interventions are most likely associated with sub-optimum environmental quality and extreme variability linked to occupancy patterns, 2) normally closed environments tend to get very unhealthy under periods of extreme pollution and intermittent/protracted disuse, 3) the elevation and floor level in addition to room use were found to be significant conditional variables in determining heat and pollutants accumulation, presumably due to the synergy between local sources and vertical transport mechanisms. Most IEQ inefficiencies and health threats could be likely mitigated by implementing automated controls and smart logics to maintain adequate cross ventilation, prioritizing building airtightness improvement, and appropriate filtration techniques. This study supports the need for continuous and capillary monitoring of different occupied spaces in educational buildings to compensate for less perceivable threats, identify the room for improvement, and move towards healthy and future-proof learning environments. Copyright © 2021 Ulpiani, Nazarian, Zhang and Pettit.

Monitoring and Assessment of Indoor Environmental Conditions after the Implementation of COVID-19-Based Ventilation Strategies in an Educational Building in Southern Spain.

Since students and teachers spend much of their time in educational buildings, it is critical to provide good levels of indoor environmental quality (IEQ). The current COVID-19 pandemic has shown that maintaining a good indoor air quality level is an effective measure to control the transmission of the SARS-CoV-2 virus. This study used sensors to monitor key IEQ factors and assess several natural ventilation scenarios in a classroom of the University of Granada. Subsequently, the IEQ factors (temperature, relative humidity, CO2 concentration, acoustic environment, and air velocity) were evaluated for the selected ventilation scenarios in the occupied classroom, and the field monitoring was carried out in two different assessment periods, winter and summer. The obtained results show that the CO2 concentration levels were well below the recommended limits. However, the maintenance of the recommended thermal and acoustic IEQ factors was significantly affected by the natural ventilation strategies (temperature and relative humidity values were very close to the outside values, and the background sound pressure level was over 35 dBA during the entire assessment). The proper measurements and careful selection of the appropriate ventilation scenarios become of utmost importance to ensure that the ventilation rates required by the health authorities are achieved.

The design of safe classrooms of educational buildings for facing contagions and transmission of diseases: A novel approach combining audits, calibrated energy models, building performance (BPS) and computational fluid dynamic (CFD) simulations.

The proposed investigation is aimed at providing useful suggestions and guidelines for the renovation of educational buildings, in order to do University classrooms safe and sustainable indoor places, with respect to the 2020 SARS-CoV-2 global pandemic. Classrooms and common spaces have to be thought again, for a new "in-presence" life, after the recent worldwide emergency following the spring 2020 pandemic diffusion of COVID-19. In this paper, starting from a real case study, and thus the architectural and technological refurbishment of an Italian University building (Campobasso, South Italy, cold climate), with the aims of improving the classrooms' quality and safety, a comprehensive approach for the retrofit design is proposed. By taking into account the necessary come back to classrooms starting, hopefully, from the next months (Autumn 2020), experimental studies (monitoring and investigations of the current energy performances) are followed by the coupling of different numerical methods of investigations, and thus building performance simulations, under transient conditions of heat transfer, and computational fluid dynamics studies, to evidence criticalities and potentialities to designers involved in the re-thinking of indoor spaces hosting multiple persons, with quite high occupancy patterns. Both energy impacts, in terms of monthly and annual increase of energy demands due to higher mechanical ventilation, and indoor distribution of microclimatic parameters (i.e., temperature, airspeed, age of air) are here investigated, by proposing new scenarios and evidencing the usefulness of HVAC systems, equipment (e.g., sensible heat recovery, without flows' contamination) and suitability of some strategies for the air distribution systems (ceiling squared and linear slot diffusers) compared to traditional ones.