Physical environmental and contextual drivers of occupants’ manual space heating override behaviour in UK residential buildings

This paper investigates the physical environmental (indoor and outdoor temperature and relative humidity, wind speed, solar radiation and rainfall) and contextual drivers (time of day) affecting occupants’ manual space heating override behaviour during the heating season based on measurements collected in ten UK dwellings. Logistic regression modelling is used to understand the probability of occupants manually overriding their scheduled heating periods. To the authors’ knowledge, these are the first stochastic models of manual heating override behaviour developed for residential buildings. The work reported in this paper suggests that occupants’ manual overrides are influenced by indoor and outdoor temperature, indoor relative humidity, and solar radiation. In addition, the effects of the physical environmental variables varied in relation to the time of day. At night, none of the physical environmental variables influenced manual overrides. In the morning, afternoon and evening, manual overrides were governed by a mix of indoor air temperature, indoor relative humidity and solar radiation. The models presented can be used in building performance simulation applications to improve the inputs for space heating behaviour in residential buildings and thus the predictions of energy use and indoor environmental conditions

A comparison between thermostat and thermostatic radiator valve setpoint temperatures in UK social housing

In the UK, in centrally heated dwellings, space heating is commonly controlled by a whole house thermostat as well as thermostatic radiator valves (TRVs) fitted on individual radiators. TRV settings define a setpoint temperature at which the radiator is switched off, in order to regulate zonal temperatures. This paper presents an analysis of the TRV setpoint temperatures which occupants’ select in living rooms and main bedrooms and provides a comparison between these and the whole house thermostat setting. The work capitalises on primary data from a socio-technical household survey undertaken in a sample of social housing in Plymouth, UK during 2015. The mean reported TRV setpoint temperature in the living rooms (n = 144) and bedrooms (n = 120) were 23.4°C and 22.1°C respectively. This result confirms that occupants prefer cooler conditions in their bedrooms and also suggests that occupants are actively using their TRVs to zonally control their heating at home to maintain comfortable thermal conditions and reduce their heating energy demand. The results also indicate that occupants’ thermostat and TRV setpoint temperatures vary according to their household and motivation, behaviour and perception characteristics. The mean reported thermostat setpoint temperature was 20.7°C for those who reported a living room TRV setting and 20.9°C for those who reported a bedroom TRV setting. This result suggests that there may be a misunderstanding of the purposes of the whole house thermostat and the individual TRVs within a central heating system. Variations in occupant heating control behaviour have an impact on occupant comfort and household energy use. The results of this study have significant implications for the planning and implementation of energy efficiency measures, behaviour change interventions as well as the design of heating controls

NET-ZERO ENERGY BUILDING OPERATOR TRAINING PROGRAM (NZEBOT)

The primary objective of the Net-Zero Energy Building Operator Training Program (NZEBOT) was to develop certificate level training programs for commercial building owners, managers and operators, principally in the areas of energy / sustainability management. The expected outcome of the project was a multi-faceted mechanism for developing the skill-based competency of building operators, owners, architects/engineers, construction professionals, tenants, brokers and other interested groups in energy efficient building technologies and best practices. The training program draws heavily on DOE supported and developed materials available in the existing literature, as well as existing, modified, and newly developed curricula from the Department of Engineering Technology & Construction Management (ETCM) at the University of North Carolina at Charlotte (UNC-Charlotte). The project goal is to develop a certificate level training curriculum for commercial energy and sustainability managers and building operators that: 1) Increases the skill-based competency of building professionals in energy efficient building technologies and best practices, and 2) Increases the workforce pool of expertise in energy management and conservation techniques. The curriculum developed in this project can subsequently be used to establish a sustainable energy training program that can contribute to the creation of new “green” job opportunities in North Carolina and throughout the Southeast region, and workforce training that leads to overall reductions in commercial building energy consumption. Three energy training / education programs were developed to achieve the stated goal, namely: 1. Building Energy/Sustainability Management (BESM) Certificate Program for Building Managers and Operators (40 hours); 2. Energy Efficient Building Technologies (EEBT) Certificate Program (16 hours); and 3. Energy Efficent Buildings (EEB) Seminar (4 hours). Training Program 1 incorporates the following topics in the primary five-day Building Energy/Sustainability Management Certificate program in five training modules, namely: 1) Strategic Planning, 2) Sustainability Audits, 3) Information Analysis, 4) Energy Efficiency, and 5) Communication. Training Program 2 addresses the following technical topics in the two-day Building Technologies workshop: 1) Energy Efficient Building Materials, 2) Green Roofing Systems, 3) Energy Efficient Lighting Systems, 4) Alternative Power Systems for Buildings, 5) Innovative Building Systems, and 6) Application of Building Performance Simulation Software. Program 3 is a seminar which provides an overview of elements of programs 1 and 2 in a seminar style presentation designed for the general public to raise overall public awareness of energy and sustainability topics

Central heating settings in low energy social housing in the United Kingdom

This paper presents essential empirical data on heating setpoint temperatures and durations from UK social housing built to low energy standards. The data was derived from living room air temperature measurements. There were single, double and multiple heating periods per day in the dwellings with mean setpoint temperatures of 20.9°C and 21.0°C on weekdays and weekends respectively. The weekday mean heating duration was 8.4 hours and for weekends, it was 9.1 hours. The results could be used to better inform the assumptions of space heating behaviour used in energy models in order to more accurately predict the space heating energy demands of dwellings

Central heating settings and heating energy demand in low energy social housing in the United Kingdom

This paper compares the central heating settings and the heating energy use performance of six flats and two houses built to low energy standards (Code for Sustainable Homes Levels 4 and 5) with a near identical flat and house built to minimum compliance only (2006 Building Regulations). As low energy houses are only recently emerging in the United Kingdom’s social housing stock, and even fewer are subject to Post Occupancy Evaluation, little is known about their performance in terms of heating behaviour and energy demand. The results show that in general, the mean weekday and weekend setpoint temperatures, heating durations and heating energy use are lower in the low energy dwellings compared to the building regulations dwellings

Photon statistics of a random laser

A general relationship is presented between the statistics of thermal radiation from a random medium and its scattering matrix S. Familiar results for black-body radiation are recovered in the limit S to 0. The mean photocount is proportional to the trace of 1-SS^dagger, in accordance with Kirchhoff's law relating emissivity and absorptivity. Higher moments of the photocount distribution are related to traces of powers of 1-SS^dagger, a generalization of Kirchhoff's law. The theory can be applied to a random amplifying medium (or "random laser") below the laser threshold, by evaluating the Bose-Einstein function at a negative temperature. Anomalously large fluctuations are predicted in the photocount upon approaching the laser threshold, as a consequence of overlapping cavity modes with a broad distribution of spectral widths.Comment: 26 pages, including 9 figure

Complex exon-intron marking by histone modifications is not determined solely by nucleosome distribution

It has recently been shown that nucleosome distribution, histone modifications and RNA polymerase II (Pol II) occupancy show preferential association with exons (“exon-intron marking”), linking chromatin structure and function to co-transcriptional splicing in a variety of eukaryotes. Previous ChIP-sequencing studies suggested that these marking patterns reflect the nucleosomal landscape. By analyzing ChIP-chip datasets across the human genome in three cell types, we have found that this marking system is far more complex than previously observed. We show here that a range of histone modifications and Pol II are preferentially associated with exons. However, there is noticeable cell-type specificity in the degree of exon marking by histone modifications and, surprisingly, this is also reflected in some histone modifications patterns showing biases towards introns. Exon-intron marking is laid down in the absence of transcription on silent genes, with some marking biases changing or becoming reversed for genes expressed at different levels. Furthermore, the relationship of this marking system with splicing is not simple, with only some histone modifications reflecting exon usage/inclusion, while others mirror patterns of exon exclusion. By examining nucleosomal distributions in all three cell types, we demonstrate that these histone modification patterns cannot solely be accounted for by differences in nucleosome levels between exons and introns. In addition, because of inherent differences between ChIP-chip array and ChIP-sequencing approaches, these platforms report different nucleosome distribution patterns across the human genome. Our findings confound existing views and point to active cellular mechanisms which dynamically regulate histone modification levels and account for exon-intron marking. We believe that these histone modification patterns provide links between chromatin accessibility, Pol II movement and co-transcriptional splicing