84 research outputs found

    Thermal responses of single zone offices on existing near-extreme summer weather data

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    There have been a number of attempts in the past to define “near extreme” weather for facilitating overheating analysis in free running buildings. The most recently efforts include CIBSE latest release of Design Summer Year (DSY) weather using multiple complete weather years and a newly proposed composite DSY. This research aims to assess how various single zone offices respond to these new definitions of near extreme weathers. Parametric studies were carried out on single zone offices through which four sampling sets of models were employed to examine the thermal responses of dry bulb temperature, global solar radiation & wind speed collectively. London weather data from 1976 to 1995 were used and the overheating assessments were made based on CIBSE Guide A & BS EN 15251. The research discovers that solar radiation and wind both influence the predicted indoor warmth with solar radiation has obvious stronger impacts than wind. No perfect correlation was found from observation and Spearman’s rank order analysis on the ranks between the weather warmth and the predicted indoor warmth. The ranks made using multiple weather parameters show better correlation than some of the dry bulb temperature only metrics. The research also discovers that the Test Reference Year weather behaves warmer than expected. It is also found that a single complete year can not represent the near-extreme consistently and there is no evidence a composite DSY is better statistically. These findings support the notion of using multiple complete warm weather years for overheating assessments

    The validity of the index of vulnerable homes : evidence from consumers vulnerable to energy poverty in the UK

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    Energy poverty is a multidimensional issue, and this means that it is difficult to understand the different levels of vulnerability to this phenomenon and its relationship with households’ quality of life. This paper presents the validation of an innovative index for the analysis of vulnerability to energy poverty according to monetary, energy and thermal comfort factors: The Index of Vulnerable Homes (IVH). The IVH goes beyond the use of single self-reported indicators of thermal comfort, and instead uses the adaptive thermal-comfort model defined in the normative UNE EN 15251:2007 to assess thermal comfort in relation to energy poverty. Furthermore, it has the potential to evaluate societal impacts of current energy poverty policies by providing the economic analysis of different situations of vulnerability. The IVH is validated by comparing its results to those obtained from a survey conducted in a small-scale study undertaken in Salford, UK. To this end, evidence from households living in terraced houses built before 1980 is used to analyse health status in terms of vulnerability to energy poverty vulnerability according to their monetary situation and the characteristics of the dwelling. In the end, the results show good agreement between both the IVH’s assessment and households’ evidence, leading to consider the IVH as a suitable approach to understanding different levels of vulnerability to energy poverty

    Evaluating the thermal comfort performance of heating systems using a thermal manikin with human thermoregulatory control

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    © International Society of the Built Environment. © The Author(s) 2014. The evaluation of the local thermal comfort and application of thermal manikins can further assist the design and selection of heating systems. This study aimed at evaluating the thermal comfort performance of different heating systems using a newly developed thermal manikin with an enhanced thermal control. The heating systems for a workstation, included a conventional radiator (convector) mounted under the window, heated floor in the occupied zone and an infrared heater mounted to the ceiling. The experiments were conducted in a test room with a façade attached to a climate chamber to simulate outdoor winter conditions. In these experiments, the supplied power for the different systems was kept constant to independently quantify the differences in their thermal comfort performance at same energy consumption. The thermal manikin was deployed in the occupied zone to evaluate the local and overall thermal comfort under each system using the equivalent temperature (Teq) approach. The thermoregulatory control used in the manikin operation is based on a model of human thermoregulation that interacts accurately with the surrounding environment through real-time measurements. The results showed that at the same energy consumption of the different systems, the variations in local thermal comfort levels were up to 1 on the comfort scale

    Overview and future challenges of nearly zero energy buildings (nZEB) design in Southern Europe

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    In times of great transition of the European construction sector to energy efficient and nearly zero energy buildings (nZEB), a market observation containing qualitative and quantitative indications should help to fill out some of the current gaps concerning the EU 2020 carbon targets. Next to the economic challenges, there are equally important factors that hinder renovating the existing residential building stock and adding newly constructed high performance buildings. Under these circumstances this paper summarises the findings of a cross-comparative study of the societal and technical barriers of nZEB implementation in 7 Southern European countries. The study analyses the present situation and provides an overview on future prospects for nZEB in Southern Europe. The result presents an overview of challenges and provides recommendations based on available empirical evidence to further lower those barriers in the European construction sector. The paper finds that the most Southern European countries are poorly prepared for nZEB implementation and especially to the challenge opportunity of retrofitting existing buildings. Creating a common approach to further develop nZEB targets, concepts and definitions in synergy with the climatic, societal and technical state of progress in Southern Europe is essential. The paper provides recommendations for actions to shift the identified gaps into opportunities for future development of climate adaptive high performance buildings. (C) 2017 Elsevier B.V. All rights reserved.info:eu-repo/semantics/publishedVersio
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