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21 pags., 25 figs., 6 tabs. -- Open Access funded by Creative Commons Atribution Licence 4.0, This study examined the design and daylight performance of a new louvre screen for office buildings. The screen was evaluated for three different material finishes: specular aluminium as a traditional material commonly used in louvres, and two types of ceramic finishes, with the intention to reduce the systems’ environmental impact. The new system was assessed taking an unshaded window, a window with a rod screen and a window with venetian blinds as references. Annual performance simulations for a full-scale room, using the lighting software Daysim, were conducted to assess the effect of the three material systems on indoor daylighting levels and distributions using both the traditional Daylight Factor and climate-based daylighting metrics (Daylight Autonomy DA and Useful Daylight Illuminance UDI). The results show that the proposed louvre system can provide satisfactory daylight levels and visual comfort within the room, while ceramics appear as a promising alternative material to be used in the production of advanced daylighting technologies., This work was supported by the Universityof Liverpool, United Kingdom.

We have developed a spatiotemporal heating control algorithm for use in homes. This system utilises a combination of relatively low-tech hardware interfaced with electric heating systems and a smartphone interface to this hardware, and a central server that progressively learns users’ room-specific presence profiles and thermal preferences. This paper describes the associated spatiotemporal heating control algorithm, its evaluation utilising the dynamic building performance simulation software EnergyPlus, and a longitudinal deployment of the algorithm controlling a quasi-autonomous spatiotemporal home heating system in three domestic homes. In this we focus on the prediction of occupants’ presence and preferred set-point temperature as well as on the calculation of optimum start time and the utilisation of user-scheduled absences; this for two comfort strategies: to maximise comfort and to minimise discomfort. The former aims to deliver conditions equating to a ‘neutral’ thermal sensation, whereas the latter targets a ‘slightly cool’ sensation with corresponding heating energy savings. Simulation results confirmed that the algorithm functions as intended and that it is capable of reducing energy demand by a factor of seven compared with EnergyStar recommended settings for programmable thermostats. Field study results align with these findings and highlight the possibility to reduce energy under the minimise discomfort strategy without compromising on occupants’ thermal comfort.

Rising energy demands place pressure on domestic energy consumption, but savings can be\ud delivered through home automation and engaging users with their heating and energy behaviours.\ud The aim of this paper is to explore user experiences (UX) of living with an automated heating system\ud regarding experiences of control, understanding of the system, emerging thermal behaviours, and\ud interactions with the system as this area is not sufficiently researched in the existing homes setting\ud through extended deployment. We present a longitudinal deployment of a quasi-autonomous\ud spatiotemporal home heating system in three homes. Users were provided with a smartphone\ud control application linked to a self-learning heating algorithm. Rich qualitative and quantitative data\ud presented here enabled a holistic exploration of UX. The paper’s contribution focuses on highlighting\ud key aspects of UX living with an automated heating systems including (i) adoption of the control\ud interface into the social context, (ii) how users’ vigilance in maintaining preferred conditions\ud prevailed as a better indicator of system over-ride than gross deviation from thermal comfort, (iii)\ud limited but motivated proactivity in system-initiated communications as best strategy for soliciting\ud user feedback when inference fails, and (iv) two main motivations for interacting with the interface –\ud managing irregularities when absent from the house and maintaining immediate comfort, latter\ud compromising of a checking behaviour that can transit to a system state alteration behaviour\ud depending on mismatches. We conclude by highlighting the complex socio-technical context in\ud which thermal decisions are made in a situated action manner, and by calling for a more holistic, UXfocused\ud approach in the design of automated home systems involving user experiences.

Many researches of overheating in buildings have focused on the optimisation of the window to wall ratio (WWR). However, the physical form of the building envelope has not been widely considered as a factor in optimisation investigations. This study examines if the optimum WWR might vary in response to slight geometrical changes to a façade's design. An evolutionary parametric design method was used to generate a range of inverted pyramidal shaped envelopes with different inclination angles for each façade. This was implemented for an existing UK Passivhaus. The WWR was set as the main variable along with a sub variable of different weather data (both current and future climate scenarios). This paper, in particular, focused on minimising the overheating during the summer while reducing the primary energy use of the building. These two parameters were set as the objectives to be optimised using the parametric tool in the dynamic thermal simulation software DesignBuilder. The calculation used batches of Energy Plus simulations using a genetic algorithm. The results showed that the optimised WWR varied significantly when implementing different façade arrangements. Optimum self-shading shapes could allow more glazing to be used while still achieving thermal comfort in summer climate.

Studies have shown that the biggest climate impacts will take place in the tropical countries of Africa. This paper examines how different building construction choices influence the thermal performance of contemporary low-income housing in the south-west Nigeria region for present and future climates. Climate-resilient and responsive dwellings need to be developed that can adapt to changing tropical climates whilst being socio-economically suited to their geographical context. This study examines the evidence of climate change in south-west Nigeria and how the region's contemporary low-income housing currently performs from energy and thermal comfort perspectives. Then, the study uses dynamic thermal modelling and current and future climate data sets to test, parametrically, how changes to the dwelling's envelope can be made to reduce climate change impact and improve occupant thermal wellbeing. As such, the typical south-west Nigerian family house type was modelled and parametrically optimised. The findings showed that some modifications to the walls, roofs and floors can help improve thermal comfort in present and future south-west Nigerian climates. The study concludes that improvements to thermal comfort and climate change resilience are realistically achievable by small modifications to a dwelling's envelope.

Thermal comfort is a key aspect when assessing a sustainable building's performance. In hot climates, such as Saudi Arabia, achieving comfort can require large amounts of cooling energy if the building has not been designed to take advantage of passive cooling techniques. In this study a thermal model of a real high-rise office building in Saudi Arabia was created and used to predict internal air temperatures, comfort levels and energy consumptions using DesignBuilder® software for summer days. Field measurements of comfort levels and internal temperatures were taken in the actual building to compare with the modelled data to check for acceptable agreement, and a small thermal comfort survey with office workers was also undertaken. The as-built office model was then parametrically altered for a range of passive strategies (including glazing area, insulation levels and thermal mass) to identify the most effective approaches to reducing cooling energy demand. The resultant optimized building was then tested under future climate scenarios for Saudi Arabia to check if the identified solutions were still effective. The study revealed that certain passive approaches could be applied successfully while maintaining an acceptable corporate image for the building - this was true for both current and future climates. The potential contribution of this study is the identification and testing of thermal comfort strategies to be used in the early design stages which will facilitate architectural design processes, practice and education.

Our aim was to establish the capability of spatially resolved acoustic spectroscopy (SRAS) to map grain orientations and the anisotropy in stiffness at the sub-mm to micron scale by comparing the method with electron backscatter diffraction (EBSD) undertaken within a scanning electron microscope. In the former the grain orientations are deduced by measuring the spatial variation in elastic modulus; conversely, in EBSD the elastic anisotropy is deduced from direct measurements of the crystal orientations. The two test-cases comprise mapping the fusion zones for large TIG and MMA welds in thick power plant austenitic and ferritic steels, respectively; these are technologically important because, among other things, elastic anisotropy can cause ultrasonic weld inspection methods to become inaccurate because it causes bending in the paths of sound waves. The spatial resolution of SRAS is not as good as that for EBSD (∼100 math formulam vs. ∼a few nm), nor is the angular resolution (∼1.5° vs. ∼0.5°). However the method can be applied to much larger areas (currently on the order of 300 mm square), is much faster (∼5 times), is cheaper and easier to perform, and it could be undertaken on the manufacturing floor. Given these advantages, particularly to industrial users, and the on-going improvements to the method, SRAS has the potential to become a standard method for orientation mapping, particularly in cases where the elastic anisotropy is important over macroscopic/component length scales.

A preference for low-density housing by Indonesian people has contributed greatly to uncontrollable urban sprawl around the peripheries of Indonesia's major cities. The cooling of low-density housing to maintain thermal comfort is energy intensive, with approximately 30-50% of conditioned air lost through ventilation and air infiltration. As Indonesia is in a hot and humid climatic region, the air's moisture level is high, and ventilation during hot weather can introduce more moisture in to buildings. Thus, the removal of excess internal humidity is essential for human comfort. The German Passivhaus building standard is effective in preserving stable interior temperatures, but its air-tight envelope might hinder the removal of excess moisture in tropical climates. The dynamic thermal simulation software DesignBuilder was used to model a typical Jakarta terraced dwelling to investigate the effects on indoor temperature and humidity on comfort and energy use from applying the Passivhaus standard. The aim was to find the optimum setting for minimising cooling and dehumidification energy in air-conditioning systems. The research examined the type of active dehumidification system that might be most suitable to work with a Passivhaus in tropical conditions to position the house's internal environment within the thermal comfort zone.