Harvesting big data from residential building energy performance certificates: retrofitting and climate change mitigation insights at a regional scale

UID/AMB/04085/2019The reduction of energy consumption and the increase in energy efficiency is currently an important cornerstone of EU policy. Energy performance certificates (EPCs) were implemented as one of the tools to promote this agenda, and are used for the energy performance assessment of buildings. In this study, the characteristics of the Portuguese dwelling stock are regionally analysed using data from approximately 523,000 Portuguese residential EPCs. Furthermore, a bottom-up building typology approach is used to assess the regional energy needs impact of retrofitting actions and to estimate the heating and cooling energy performance gaps of the whole dwelling stock, as well as the potential CO2 emissions resulting from the gaps' potential offset due to increase thermal comfort. The results show that Portuguese residential buildings have very low energy performance, with windows and roofs being identified as the most energy inefficient elements. Roof retrofitting has the highest potential for the reduction of energy needs. The estimated heating and cooling energy performance gap amount to very significant percentages, due to the poor performing building stock but also very low energy consumption levels, with probable consequences for the thermal comfort of occupants. Assuming the current energy mix, carbon emissions would be 9.8 and 20.2 times higher associated with heating and cooling, respectively, if the actual final energy consumption were to match the estimated theoretical values derived from building regulation. This study demonstrates several application cases and leverages the potential of the individual EPC, increasing the detail in the dwelling stock characterization and energy performance estimation, revealing its value for energy retrofit and climate change mitigation assessments, as well as establishing the ground for future work related to building retrofits, energy efficiency measure implementation, climate change mitigation, thermal comfort, and energy poverty studies.publishersversionpublishe

Design of Inverter Based CMOS Amplifiers in Deep Nanoscale Technologies

In this work, it is proposed a fully differential ring amplifier topology with a deadzone voltage created by a CMOS resistor with a biasing circuit to increase the robustness over PVT variations. The study focuses on analyzing the performance of the ring amplifier over process, temperature, and supply voltage variations, in order to guarantee a viable industrial employment in a 7 nm FinFET CMOS technology node for being used as residue amplifier in ADCs. A ring amplifier is a small modular amplifier, derived from a ring oscillator. It is simple enough that it can quickly be designed using only a few inverters, capacitors, and switches. It can amplify with rail-to-rail output swing, competently charge large capacitive loads using slew-based charging, and scale well in performance according to process trends. In typical process corner, a gain of 72 dB is achieved with a settling time of 150 ps. Throughout the study, the proposed topology is compared with others presented in literature showing better results over corners and presenting a faster response. The proposed topology isn’t yet suitable for industry use, because it presents one corner significantly slower than the rest, namely process corner FF 125 °C, and process corner FS -40 °C with a small oscillation throughout the entire amplification period. Nevertheless, it proved itself to be a promising technique, showing a high gain and a fast settling without oscillation phase, with room for improvement.Neste trabalho, é proposta uma topologia de ring amplifier com a deadzone a ser criada através de uma resistência CMOS com um circuito de polarização para aumentar a robustez para as variações PVT. O estudo foca-se em analisar a performance do ring amplifier nas variações de processo, temperatura e tensão de alimentação, de forma a garantir um uso viável em indústria na tecnologia de 7 nm FinFET CMOS, para ser usado como amplificador de resíduo em ADCs. Um ring amplifier é um pequeno amplificador modular, derivado do ring oscillator. É simples o suficiente para ser facilmente projetado usando apenas poucos inversores, condensadores e interruptores. Consegue amplificar com rail-to-rail output swing, carregar grandes cargas capacitivas com carregamento slew-based e escalar bem em termos de performance de acordo com o processo. No typical process corner, foi obtido um ganho de 72 dB com um tempo de estabilização de 150 ps. Durante o estudo, a topologia proposta é comparada com outras presentes na literatura mostrando melhores resultados over corners e apresentando uma resposta mais rápida. A topologia proposta ainda não está preparada para uso industrial uma vez que apresenta um corner significativamente mais lento que os restantes, nomeadamente, process corner FF 125 °C, e outro process corner, FS -40 °C, com uma pequena oscilação durante todo o período de amplificação. Todavia, provou ser uma técnica promissora, apresentando um ganho elevado e uma rápida estabilização sem fase de oscilação, com espaço para melhoria

Youth’s physical activity and fitness from a rural environment of an Azores Island

This study aimed to characterize and compare physical activity (PA) and fitness levels by sex in 109 students of a rural environment. The participants were between 15 and 20 years old, from the Santa Maria High School in the Azores’ Santa Maria island. PA levels were assessed by International Physical Activity Questionnaire (IPAQ)-short form. The physical fitness was evaluated by the Fitnessgram battery tests. The sample of this study were physically active, 67.9% were classified with high and moderate PA levels. Regarding the sex comparisons, no significant differences between PA levels were founded. However, males presented higher values of vigorous physical activity, whereas females spent more time in moderate activity, such as walking. Moreover, females had more time in sitting positions during the week and weekend. Regarding the physical fitness levels, males presented significantly higher performances in the upper strength (p < 0.001) and aerobic capacity tests (p < 0.001), whereas females showed higher values in the sit and reach test (p < 0.001), in the trunk lift test (p < 0.005), and in the fat mass values (p < 0.001). It seems reasonable to assume that there is a sociodemographic influence on the PA and physical fitness levels in our sample. We may speculate that rural life provides more opportunities for youth for being physically active than urban life. No differences were founded between sexes for physical activity. However, differences were found between sex for strength, flexibility, cardiorespiratory fitness, and body composition. That might be explained by the biological differences and the type of physical activity habits that each sex use to have in rural environmental.This work is supported by National Funds through FCT—Foundation for Science and Technology under the project UID04045/2020 and was approved by the Education Regional Direction with process number DSP/15-29.info:eu-repo/semantics/publishedVersio

Study of postural misalignments between sex, school cycle and physical activity

This study aimed to characterize and compare postural behaviour between gender, school cycles and PA levels in 213 students, aged between 10 and 20 years, from Escola Básica e Secundária de Santa Maria. Postural assessment was made through visual scan analysis in a symmetrograph and the Adams test. PA level assessment was made using the IPAQ. Postural behaviour presented high percentages of imbalances in both sexes, with the highest prevalence in the head lateral flexion, shoulders level asymmetry, scoliosis, gibbosity, forward head and protracted shoulders. Lumbar scoliosis was significantly related to pelvic asymmetry (p < .001), protracted shoulders were related to forward head (p = .010) and dorsal hyperkyphosis (p = .048) and lumbar hyperlordosis was more prevalent in subjects with pelvic anteversion (p < .001). Dorsal hyperkyphosis manifested in males with a markedly higher prevalence than females (p = .006). Postural imbalances were present at all ages, with pelvic anteversion decrease (p = .028) with school cycles progression. Our sample proved to be physically active with 73.9% categorized with high and moderate levels of PA. Higher PA levels where related to forward head lower percentages (p = .006). It should be highlighted the importance of postural assessment school students.This work is supported by National Funds through FCT - Foundation for Science and Technology under the project UID04045/2020 and was approved by the Education Regional Direction with process number DSP/15-29

A Sequential Multi-Staged Approach for Developing Digital One-Stop Shops to Support Energy Renovations of Residential Buildings

Publisher Copyright: © 2022 by the authors.Buildings account for 40% of the European Union’s energy consumption. Deep energy renovation of residential buildings is key for decarbonization and energy poverty alleviation. However, renovation is occurring at far below the needed pace and depth. In this context, building renovation one-stop shops, which bring all project phases under one roof and provide advice, support, and finance to households, are highlighted as a promising solution. Nevertheless, this model is still absent or under-developed in most European countries and remains understudied in the scientific literature. Therefore, the present research goals are as follows: (i) to provide a critical review of emerging one-stop shop models; (ii) to streamline the deployment of building renovation digital one-stop shops by piloting a sequential multi-staged approach for Portuguese households and proposing it for replication elsewhere; and (iii) to compare case-study insights with other one-stop shops and discuss the notion in the context of the European Renovation Wave. In total, for the Portuguese case-study, five steps were conducted. The first three—stakeholder mapping, expert interviews, and customer journey—aimed to gather intel on the local energy renovation market. The results from these stages informed the design of the platform (fourth step). Finally, a post-launch market consultation survey gathered user feedback (fifth step). Insights from this study suggest that digital one-stop shops, while providing a helpful tool to close information gaps and activate specific audiences, may be insufficient on their own. As such, a more comprehensive set of instruments supporting households is needed to accelerate building renovation.publishersversionpublishe

A comparative analysis between local and exchange university students from Montevideo, Lisbon, and Padua

Funding Information: CC acknowledges the support given by the Calouste Gulbenkian Foundation through the Environmental Sustainability Grant from the Novos Talentos Científicos that supported the development of this work and the open access fee, and for organizing discussion sessions throughout the progress of the research. Publisher Copyright: Copyright © 2023 Castro and Gouveia.Energy Poverty (EP) is a growing concern in EU and national policies. Limited research has been conducted on students' perception of EP and vulnerability to EP, especially on how this may be modified if the student is a local or an exchange university student and how this interacts with the season (i.e., summer and winter). Therefore, the present research aims to deepen this understanding by analyzing and comparing students' perceptions of EP and exploring their vulnerability to EP, considering their background and the city they live in, using Montevideo in Uruguay, Lisbon in Portugal, and Padua in Italy, as case studies. To achieve these aims, two populations of university students in each city were surveyed: one of Local Students (LS) and another of Exchange Students (ES). Responses from 295 students to an online survey with 44 questions covering several aspects of EP and energy awareness, such as energy consumption habits, vulnerability drivers, energy equipment, and lived experience in maintaining comfortable internal temperatures, were collected in 2022. Differences between the perception of LS and ES in each city were analyzed, as well as differences in students' perceptions among cities. Although it is difficult to generalize, comfort levels seem to vary according to location, type of students, and season, but according to the results, there seems to be an interaction between these three factors. According to this research, most students did not identify themselves as living in EP, but several populations perceived discomfort in both winter and summer, showing their vulnerability to EP.publishersversionpublishe

Residential Sector Energy Consumption at the Spotlight: From Data to Knowledge

Energy consumption is at the core of economic development, but its severe impacts on resources depletion and climate change have justified a call for its general reduction across all economic activities. Lowering households’ energy demand is a key factor to achieve carbon dioxide emission reductions as it has an important energy-saving potential. Households in the European Union (EU28) countries have a significant weight (25%) in the total final energy consumption. However, a wide range of variation is observed within the residential sector from 7.6 to 37.4 GJ per capita/annum, with the lowest consumption indicator observed in Southern EU countries. Energy consumption in the residential sector is a complex issue, explained by a combination of different factors. To pinpoint how to reduce energy consumption effectively while deliver energy services, we need to look not just at technology, but also to the factors that drive how and in what extent people consume energy, including the way they interact with technology (i.e., energy efficiency). The main objective of this research is to understand the differences in energy consumption arising from different socio-demographic, technologic, behavioral and economic characteristics of residential households. This research brings to the spotlight the needs and benefits of looking deeper into residential sector energy consumption in a southern European country. Portugal and the municipality of Évora, in particular, were selected as case studies. Residential sector consumption is a moving target, which increase the complexity of adequate policies and instruments that have to address the bottleneck between increase demand for e.g. climatization due to current lack of thermal comfort and to comply with objectives of increased energy efficiency which ultimately intend to reduce energy consumption. This calls for different levels of knowledge to feed multiscale policies. This dissertation expands the understanding of energy consumption patterns at households, consumers’ role in energy consumption profiles, indoor thermal comfort, and the levels of satisfaction from energy services demand. In a country potentially highly impacted by climate change, with low levels of income and significant lower energy consumption per capita compared to the EU28 average, looking into these issues gains even more importance. The work combines detailed analysis at different spatial (national, city and consumers level) and time scales (hour to annual) taking advantage of diverse methods and datasets including smart meters’ data, door to door surveys and energy simulation and optimization modelling. The results identify (i) ten distinct residential sector consumer groups (e.g., under fuel poverty); (ii) daily and annual consumption patterns (W, U and flat); (iii) major energy consumption determinants such as the physical characteristics of dwellings, particularly the year of construction and floor area; climatization equipment ownership and use, and occupants’ profiles (mainly number and monthly income). It is (iv) recognized that inhabitants try to actively control space heating, but without achieving indoor thermal comfort levels. The results also show (v) that technology can overweight the impact of practices and lifestyle changes for some end-uses as space heating and lighting. Nevertheless, important focus should be given to the evolution in the future of uncertain parameters related with consumer behavior, especially those on climatization, related to thermal comfort and equipment’s use. Furthermore, the research work presents a (vi) bottom-up methodology to project detailed energy end-uses demand, and (vii) an integrated framework for city energy planning. This work sets the ground for the definition of tailor-made policy recommendations for targeted consumer groups (e.g., vulnerable consumers) and climatization behavior/practices to reduce peak demand, social support policies, energy efficiency instruments and measures, renewable energy sources integration, and energy systems planning

Study of the association between postural misalignments in school students

Nowadays, postural misalignments prevalence in students is increasingly evident and its early detection is the best way to prevent complications in adulthood. It is also known that postural problems appear to have association between them. The aim of this study was to characterize and study the association between spine, scapular and pelvic girdles postural misalignments in 213 school students (124 males and 89 females), aged between 10 and 20 years, from Escola Básica e Secundária de Santa Maria (EBSSM). To understand the relation between postural misalignments we compare the head positioning with the shoulder girdle, the shoulder girdle with the dorsal spine and the lumbar spine with the pelvic girdle. The postural assessment was made by visual scan analysis in a symmetrograph based on photogrammetry and the Adams. We found high percentages of postural misalignments in all subjects. High prevalence was observed in the posterior view of the frontal plane in the head lateral flexion, shoulders vertical asymmetry, scoliosis and in the presence of gibbosity, whereas, in the right view of the sagittal plane forward head posture and protracted shoulders were observed. The lumbar scoliosis was more prevalent in subjects with iliac crest’s asymmetry (p < 0.001) and forward head posture was significantly related to the subjects with protracted shoulders (p = 0.010). The protracted shoulders were more prevalent in subjects with dorsal hyperkyphosis (p = 0.048) and lumbar hyperlordosis was related to the subjects with pelvic anteversion (p < 0.001). The students’ postural assessment showed a wide variety of postural misalignments. It also seems evident that there is a relationship between their occurrences. It should be highlighted the importance of postural assessment in physical education (PE) classes to determine postural misalignments among school students.This work is supported by the Douro Higher Institute of Educational Sciences and the Portuguese Foundation for Science and Technology, I.P. (project UIDB/04045/2021).info:eu-repo/semantics/publishedVersio

Mapping regional vulnerability to energy poverty in Poland

Funding Information: Funding: This article is based upon work from COST Action ‘European Energy Poverty: Agenda Co-Creation and Knowledge Innovation’ (ENGAGER 2017–2021, CA16232), supported by COST (European Cooperation in Science and Technology). Lilia Karpinska and Sławomir S´miech gratefully acknowledge financial support from the National Science Centre in Poland (grant no. 2018/29/N/HS4/ 02813). João Pedro Gouveia and Pedro Palma acknowledge and are thankful for the support provided to CENSE by the Portuguese Foundation for Science and Technology (FCT) through the strategic project UIDB/04085/2020. Pedro Palma’s work has also been supported by FCT through the scholarship SFRH/BD/146732/2019.Raising concerns about the effectiveness of the energy poverty policy actions in Poland, such as Clean Air and Stop Smog, brings forward the need to apply different strategies to identify the energy poor. More than 13.7% of Polish households were energy poor in 2018 according to the ability-to-keep-home-warm indicator. This study proposes enhancing the model-based approach to measure households’ energy poverty. Our goal is to assess regional vulnerability to energy poverty in Poland. The study relies on three national datasets and is conducted in two steps. The Energy Consumption Survey (2018) and the Household Budget Survey (2018) provide data for modeling household’s energy poverty in the first step. The Local Data Bank (2019) gives information on the potential factors increasing regional vulnerability to energy poverty evaluated in the second step. We apply multiple linear regression to identify energy-poor households and principal components analysis to examine the regions’ vulnerability factors. As a result, we produce several maps showing the spatial distribution of vulnerability to energy poverty in 380 Polish districts. Our results indicate that some northern, southern and eastern districts in Poland are primary targets of energy poverty policy actions.publishersversionpublishe