In-use Energy Performance Study Of Automated Smart Homes

Domestic energy demand has been high on the carbon reduction agenda for some time. Today new homes are being designed following the “fabric first” principle which is reducing heat demand, but it is shifting the design challenge to ventilation. Further energy reductions and comfort improvements are needed. It is frequently proposed that automated control systems can achieve this. However, the technologies involved are currently considered expensive and complicated. There is little published evidence of how these types of systems perform in use, which leads to scepticism. This research study aims to test the hypothesis that automated demand-controlled heating and ventilation can provide a good indoor environment while reducing energy consumption in “real-life” homes. A year-long case study was conducted using six occupied, neighbouring dwellings installed with a low-cost automated building control system. The energy consumption figures recorded were compared to the values predicted by the Standard Assessment Procedure and by a Dynamic Simulation Model, and compared to Passivhaus standard. Significant savings have been identified. The results of this study show that an automated control system can lead to very low energy, and hence low carbon homes at a price-point that would incentivise widespread role out. This means that such systems have the potential to make a considerable contribution to reducing the carbon footprint of housing stock, and hence to meeting carbon reduction targets

Closed loop material cycle construction : defining and assessing closed loop material cycle construction as a component of a comprehensive approach to sustainable material design in the context of sustainable building

This thesis sets out to identify and define a set of criteria by which building materials and elements can be assessed in terms of forming part of closed loop material cycle, and from which legally binding targets can be developed to support good practice in relation to sustainable material design in the built environment. An initial investigation into the research context of sustainability applied to the built environment and the means of implementing good practice in the building industry is followed by a review of selected sustainable material design philosophies. Based on a synthesis of these philosophies and how they can be applied to building practice, the dissertation proposes a concept for a comprehensive approach to sustainable material design that incorporates a requirement for close loop material cycle construction. The characteristics of closed loop material cycles and their relevance to the building industry are considered, and a set of criteria for closed loop material cycle construction is formulated, drawing on existing research and guidance on natural recovery and design for deconstruction and recycling. The criteria are applied in a pilot assessment of selected materials, building elements and three whole house designs, which suggests that closed loop material cycle construction is technically feasible. The assessment results are used to suggest possible practical good practice targets for closed loop material cycle construction content that are achievable for mainstream housing construction and that can bring significant benefits in terms of improving the sustainability of construction developments. The dissertation concludes with a critical reflection on the conceptual development and practical application of the closed loop material cycle criteria and proposes an agenda for further research in this field.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

A natural ventilation alternative to the Passivhaus standard for a mild maritime climate

This study examines the need in mild maritime climates, such as the southern areas of the UK, for mechanical ventilation with heat recovery (MVHR) as required by the German Passivhaus standard. It considers the comfort, air quality and energy impacts of MVHR versus natural ventilation and reviews the post-occupancy monitoring data of two flats in Cardiff designed to Passivhaus standards, one of which had been operated as a naturally ventilated building rather than with MVHR. The energy consumption of this free-running flat was significantly lower (36 kWh primary energy/m²a) than the Passivhaus Planning Package modeling had predicted (93 kWh primary energy/m²a) with no adverse effects on occupant comfort, air quality or excessive humidity, and advantages of lower capital cost and maintenance. The paper concludes that in climates with mild winters and cool summers the use of MVHR could be omitted without compromising comfort levels and achieving at least equivalent energy savings resulting from adopting the Passivhaus model and at a lower capital cost. This suggests the potential for a naturally ventilated, ultra-low energy model with lower capital investment requirements and lower disruption when applied to retrofit that would facilitate its mainstream adoption

Evaluation of indoor environment in super-insulated naturally ventilated housing in the south of the United Kingdom

Improved energy performance standards are resulting in better insulated and more airtight building. In such buildings ventilation can be provided by natural ventilation and decentralised mechanical systems or with whole-house mechanical ventilation with or without heat recovery. Whole-house mechanical ventilation systems are associated with operational energy use, embodied energy and maintenance. Conversely, natural ventilation systems that provide insufficient fresh air are thought to potentially compromise indoor air quality and may be associated with overheating in summer. This paper reports on a study funded by the NHBC Foundation of the indoor environment of eight superinsulated naturally ventilated homes in the south of the UK. One year of monitoring temperature, relative humidity, CO2, CO, NO2, CH2O and TVOC was undertaken. In addition a building survey was undertaken and the occupants were interviewed in relation to their perceived comfort levels. The buildings are currently being modelled to simulate changes in occupancy, airtightness and ventilation and construction. Initial monitoring results suggest good air quality and comfortable internal environments can be achieved with natural ventilation. No correlation was found between CO2 and TVOC levels. Building occupants were shown to effectively control their environment and in certain cases were instrumental in maintaining comfortable internal temperature

Thermal comfort and Indoor Air Quality in super-insulated housing with natural and decentralised ventilation systems in the south of the United Kingdom

​Improved energy performance standards are resulting in better insulated and more airtight building. In such buildings ventilation can be provided by natural means alone or in conjunction with extract mechanical ventilation or with wholehouse mechanical ventilation with or without heat recovery. This paper reports on a study funded by the NHBC Foundation of the indoor environment of eight super-insulated homes with natural and decentralised ventilation systems in the south of the UK. The aim was to examine the effectiveness of such ventilation options. The buildings were monitored for one year in relation to temperature, relative humidity, CO2, CO, NO2, CH2O and TVOC. The building occupants’ feedback and IES building modelling triangulated the site data. The study showed natural and decentralised ventilation systems provided good air quality in the case study buildings and allowed users to create comfortable thermally differentiate environments in response to their preferences

Mercury acetate produced by metallic mercury subjected to acoustic cavitation in a solution of acetic acid in water.

Mercury acetate (MA) can be obtained by metallic mercury immersed in a mixture of deionised, bidistillated water (dbw) and acetic acid. We show that MA crystallization time is drastically reduced if the previous mixtures are subjected to acoustic cavitation. The largest quantity of crystals is obtained by a concentration of acetic acid of about 7% in volume. NMR analysis of identical mixtures in the presence of mercury, performed as soon as possible after cavitation, showed the largest quantity of mercury acetate molecules, for the same concentration of acetic acid of 7% in volume

Musculoskeletal Diseases Role in the Frailty Syndrome: A Case-Control Study.

Frailty syndrome severely burdens older age, and musculoskeletal diseases are of paramount importance in its development. The aim of this study is to unravel the contribution of musculoskeletal diseases to frailty syndrome. This is a case-control study, and we enrolled 55 robust community-dwelling age- and gender-matched patients, with 58 frail and pre-frail subjects. Frailty was diagnosed according to the Fried criteria (FP), and the Fragility Index (FI) was calculated. In all the subjects, a comprehensive geriatric assessment was carried out. Their nutritional status was evaluated by the Mini Nutritional Assessment and Bioelectrical Impedance Analyses. Their bone density (BMD), bone turnover, muscle mass, strength and performance were evaluated. Here, we show that the prevalence of frailty varies according to the diagnostic criteria used and that FP and FI showed a moderate to good agreement. Despite age and gender matching, frail subjects had lower muscle strength, performance and BMD. Their quality of life and cognitive performance were reduced in the frail subjects compared to the robust ones. Muscular strength and performance, together with mood, significantly predicted the diagnosis of frailty, whereas BMD and bone turnover did not. In conclusion, we show that sarcopenia plays a pivotal role in predicting the diagnosis of frailty, whereas osteoporosis does not

Episiotomy in Southern Brazil: prevalence, trend, and associated factors

OBJECTIVE To identify and analyze the prevalence, trend, and factors associated with episiotomy in Rio Grande, in the state of Rio Grande do Sul, Southern Brazil. METHODS A single, standardized questionnaire was applied to all pregnant women, residents in the municipality of Rio Grande, who had children in local hospitals between January 1 and December 12 of the years 2007, 2010, 2013, 2016 e 2019. Demographic and socioeconomic characteristics were investigated, as well as the assistance received during pregnancy and delivery. Chi-square test was used to compare proportions and Poisson regression with robust variance adjustment was used for multivariable analysis. Prevalence ratio (PR) was used as effect measure. RESULTS Among the 12,645 births that occurred in the five years, 5,714 (45.2%) were vaginal delivery. Of these mothers, 2,930 (51.3%; 95%CI: 50.0%–52.6%) underwent episiotomy. Over this period, the episiotomy rate decreased from 70.9% (68.4–73.5) in 2007 to 19.4% (17.1–21.7) in 2019. Adjusted analysis showed a high PR of episiotomy occurrence among women who were young (PR = 2.23; 95%CI: 1.89–2.63), had higher education (PR = 1.21; 95%Cl: 1.03–1.42), had a higher family income (PR = 1.25; 95%CI: 1.10–1.41), were primiparous (PR = 3.41; 95%CI: 2.95–3.95), had prenatal care in the private sector (PR = 1.25; 95%CI: 1.07–1.46), had oxytocin-induced labor (PR = 1.18; 95%CI:1.09–1.27), underwent forceps (PR = 1.32; 95%CI: 1.16–1.50), and whose newborn weighed 4,000 g or more (PR = 1.43; 95%CI: 1.14–1.80). CONCLUSION Although the prevalence of episiotomy fell sharply within the studied period, its occurrence is more likely among women at lower risk of birth complications