Measuring and modelling the energy demand reduction potential of using zonal space heating control in a UK home

Most existing houses in the UK have a single thermostat, a timer and conventional thermostatic radiator valves to control the low pressure, hot water space heating system. A number of companies are now offering a solution for room-by-room temperature and time control in such older houses. These systems comprise of motorised radiator valves with inbuilt thermostats and time control. There is currently no evidence of any rigorous scientific study to support the energy saving claims of these zonal control systems. This thesis quantifies the potential savings of zonal control for a typical UK home. There were three components to the research. Firstly, full-scale experiments were undertaken in a matched pair of instrumented, three bedroom, un-furbished, 1930s, test houses that included equipment to replicate the impacts of an occupant family. Secondly, a dynamic thermal model of the same houses, with the same occupancy pattern, that was calibrated against the measured results. Thirdly, the experimental and model results were assessed to explore how the energy savings might vary in different UK climates or in houses with different levels of insulation. The results of the experiments indicated that over an 8-week winter period, the house with zonal control used 12% less gas for space heating compared with a conventionally controlled system. This was despite the zonal control system resulting in a 2 percentage point lower boiler efficiency. A calibrated dynamic thermal model was able to predict the energy use, indoor air temperatures and energy savings to a reasonable level of accuracy. Wider scale evaluation showed that the annual gas savings for similar houses in different regions of the UK would be between 10 and 14% but the energy savings in better insulated homes would be lower

Calculating the Domestic Operational Rating of gas-fired, centrally-heated homes: equations and results for example homes and the D114 sample. Supplementary Information to ‘‘A Domestic Operational Rating for UK homes: Concept, Formulation and Application, Energy and Buildings, Lomas KJ, et.al. 2019”

Calculating the Domestic Operational Rating of gas-fired, centrally-heated homes: equations and results for example homes and the D114 sample.Please see the associated article for more information: https://doi.org/10.1016/j.enbuild.2019.07.021; https://dspace.lboro.ac.uk/2134/38339</div

Energy Flexibility in a Planning Context: A Pilot Project

This award-winning poster was presented at the annual ERBE-LoLo Colloquium in 2021 to the flexibility and resilience category. The poster summarises a pilot project completed prior, reflecting on the impacts of energy flexibility at the building level on urban planning. Initial findings from this pilot project helped shape future research throughout the PhD project.A building energy model was developed using Dymola (Modelica Language) to test different technology arrangements and explore the impact of parameter variation through a sensitivity analysis. Key findings:Optimising for operating cost results in increased annual demand in scenarios without self-generationIntroducing active storage increases capital costs but can reduce operating costsHot water tanks are the most cost-effective storage solution, but in combination with solar PV and batteries improves the return on investmentThe ERBE CDT is the EPSRC and SFI Centre for Doctoral Training in Energy Resilience and the Built Environment.</p

Should We Regulate for Energy Flexibility?

This poster was presented at the annual ERBE-LoLo Colloquium in 2023 to the flexibility and resilience category. Following a 6-month secondment with the Department for Levelling Up, Housing and Communities (DLUHC), a refreshed stance was proposed on the "usefulness" of legislating for energy flexibility in buildings. The poster summarises some of the potential impacts and some of the methods that a flexibility indicator or target could have. Initial findings from this work helped shape the discussion and context of the PhD project.Key findings:Energy flexibility is required for system balancing, but mandating for building energy flexibility capability may have unintended consequences at the single-building level.Mandating flexibility capability would be costly and there is uncertainty about how much benefit it could provide at a regional or national scale.A smart building rating may be a cheaper way of incentivising flexibility in buildings but needs careful balancing between its goals and a robust method of quantificationThe ERBE CDT is the EPSRC and SFI Centre for Doctoral Training in Energy Resilience and the Built Environment.</p

Simulation assisted design exploration to evaluate view and energy performance of window shading

One of the most effective passive cooling strategies for buildings in a hot and dry climate is to use suitable shading devices. Dense shading is more effective in reducing the energy required for cooling, but it reduces visibility through openings. This paper explores the influence of more than 300 fixed shading systems on view to outside and energy consumption of a typical south-facing office building in Tehran, Iran. The shading devices vary in depth, number, angle, and thickness in three types of horizontal, vertical and egg-crate. Among the optimised shading devices, the horizontal shadings were the most frequent and on the contrary, no egg-crate shadings were found. The results showed that when the view to the outside is considered equally important as the energy consumption, the horizontal shadings are most suited. However, where the view to the outside has priority to energy consumption, vertical shadings are the best choice. The smaller the width and number of louvres, the higher the chance to reach the optimal performance. The research objectives were found not sensitive to the louvres’ thickness and angle

The summertime overheating signature of homes

Summertime overheating of homes has been demonstrated in many countries. Raised internal temperatures have a detrimental impact on health, comfort, and well-being. Climate change is predicted to cause hotter summers in many countries with more frequent and intense heatwaves. There is, therefore, a need to understand the likely overheating risk of homes in these future summers. Simple physics-based models are very limited in their ability to produce valid assessments of overheating. More complex modelling using Dynamic Thermal Simulation (DTS) software can simulate internal temperatures when the modelled building is subject to future weather files. There are, however, acknowledged uncertainties attached to the overheating determined from these simulations. Data-driven models can use temperature monitored in existing buildings to predict future overheating risk. This paper presents the idea of ‘overheating signatures’, simple mathematical models which relate the internal temperature in spaces to the external conditions and occupant behaviour. Synthetic data from a single-zone building was used to derive such models and evaluate their ability to ‘predict’ overheating for different UK weather conditions. Analysis of the data revealed that there was a strong correlation between number of hours overheated and the warm period average outdoor air temperature (R2 above 0.94). Applying the regression model to two different UK locations showed high correlation between overheating results predicted by the mathematical model and those from dynamic thermal simulation (R2, 0.94 to 0.98). Based on these findings we conclude that data-driven models have an important role to play in evaluating overheating risk. Future work is, however, needed to refine the mathematical models with data on a daily timescale and to test them on real-world buildings. Although this research has a focus on UK dwellings, it is likely of interest to other countries with a temperate climate

Thermal characterisation of composite walls made from waste materials

Sustainable development has been an ever-growing global concern over the years, especially with respect to the environment. The construction sector is a major cause for concern due to the devastating effects traditional building materials, manufacturing processes and procurement, have on the environment. Inadequate housing in developing countries is also another major sustainable development challenge. These illustrate the cogent need for developing new methods of delivering sustainable housing that can be accessible to lowincome communities who have little or no access to finances. This study compares the thermal performance of low-cost building components made from incorporating waste materials in cement blocks, thereby reducing the quantity of new materials needed. Three samples (wall panels) were made. Each panel was 330mm × 330mm × 240mm and incorporated 25 × 500ml plastic bottles laid horizontally in rows. A sand and cement mixture (ratio 1:3) was used as a binder and filled the gaps between the plastic bottles. The bottles in the first sample were filled with sand, those in the second were filled with water, and those in the third with used plastic carrier bags. A guarded hot box was developed to experimentally measure the U-values of the samples following the BS EN ISO 8990 standards. It was observed that the samples with the plastic bags had the lowest Uvalue, about 60% lower than samples with sand. The results show a promising potential for low-grade plastic waste to be used as a means of improving the thermal performance of low-cost buildings.</p

Assessing the self-rated sleep quality in UK homes, based on an online survey

The aim of this study was to understand the self-rated sleep quality of occupants in UK homes and their association with bedroom condition. An online survey questionnaire was designed to understand the thermal comfort while sleeping, sleep quality and the physiological factors that affect sleep. The survey was administered for a period of two months (June-July 2022) in the UK. The survey asked particularly about the sleep disorder symptoms, sleep quality in summers, and thermal sensations and preferences while sleeping in summers. The study is observational and based on subjective responses of the occupants living in the UK homes. Analysis of SDS-CL-25 shows that only 22% (35 out of 158) respondents had no positive endorsements for any of the 13 sleep disorders. 41% respondents have a sleep efficiency less than 85% which is recommended by the National Sleep Foundation. Sleep disturbance in majority was reported due to heat/ warm bedroom conditions followed by noise and dryness in the air. More than 50% of respondents expressed poor satisfaction with sleep and bedroom temperature during summers. The study highlights the prevalence of sleep disorders, and dissatisfaction with sleep quality in UK homes.</p

The impact of human occupancy in thermal performance of a historic religious building in sub-humid temperate climate

The level of human occupancy in historic religious buildings influences the internal heat gains and thus the thermal comfort of the users. The temperate climate represents a challenge due to variations in temperature and relative humidity throughout the year, which are by no means extreme. Knowledge regarding human occupancy in historic religious buildings in temperate climates increases the possibilities of controlling and staying within a given comfort range for the users benefit. The objective was to determine the impact of occupancy on the thermal performance of a historic religious building located in sub-humid temperate climate, to increase the knowledge and to generate opportunities to decrease the excessive use of active systems prevalent today. The objective was approached with a numerical method that included monitoring periods and dynamic simulation to determine a novel passive cooling system that would maintain a determined comfort temperature for the longest time in summer. By implementing a novel passive cooling system, the results showed an impact on the operative temperature according to occupancy level, which reduced the cooling degree-hour by 80% and 66% at the upper occupancy with 80% and 90% satisfaction levels, respectively

0219 Experimental study on thermal comfort and sleep quality of sleeping people in overheated bedroom conditions in the UK [Abstract]

This is a Journal Article Abstract.</p