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Biography
Professor Glew is Head of Energy Efficiency and Policy at the Leeds Sustainability Institute. He manages large interdisciplinary retrofit evaluation projects for the LSI, including undertaking Building Performance Evaluation (BPE) field tests, evaluation in use monitoring of energy and indoor air quality including smart meter data, as well as investigate the potential for behaviour change methods to improve occupant comfort and reduce instances of damp, and performing hydrothermal and energy modelling of buildings. David is an established expert in retrofit evaluation, he was seconded into Government (BEIS) and is still often called upon for guidance on issues facing domestic energy efficiency policy and research, he is also a regular contributor to national and local TV and Radio and has appeared on podcasts on domestic energy efficiency and retrofit related issues.
His major research projects have included; the Leeds Core Cities Green Deal investigations into retrofit performance; an investigation in to risks and benefits on thin internal wall insulation (TIWI) ; and one of the UK’s largest single retrofit research project undertaken; the £3 million DEEP project, looking into the risks and benefits of whole house versus piecemeal retrofits and the efficacy of existing modelling tools. David has managed many research projects for government, research councils and industry, as well as Knowledge Transfer Partnerships (KTP) on various topics ranging from investigating the thermal performance of local housing associations’ housing stock before and after an eco-renovation, analysing and comparing energy efficiency between different supermarket stores, understanding how buildings affect thermal comfort and how occupant behaviour impacts the risk of damp in homes.
David has authored multiple academic papers and Government reports into the technical and social opportunities and barriers for retrofit in the UK and is also interested in evaluating the performance of innovative BPE tools and energy efficiency products, as well as performing Life Cycle Assessments on products and processes. David is also qualified as a PAS2035 Retrofit Coordinator via the Retrofit Academy’s Level 5 Diploma in Retrofit Coordination & Risk Management course. He undertakes peer review for academic journals, performs external PhD examinations for other universities and acts as a Director of Studies for LBU.
Industry Expertise (2)
Research
Education/Learning
Areas of Expertise (2)
Sustainability
Buildings
Links (7)
- ResearchGate Profile
- University Profile
- Why the Government's new energy strategy won't be enough to keep homes warm – School of Built Environment, Engineering and Computing Blog
- The end of gas boilers: Challenges of switching to electricity and evaluating the government's plan – School of Built Environment, Engineering and Computing Blog
- The end of gas boilers: Problems and solutions – School of Built Environment, Engineering and Computing Blog
- Smart Asset & Estate Management Conference Speaker Profile
- The Conversation Author Profile
Languages (1)
- English
Media Appearances (2)
Cheltenham Science Festival back for its 20th birthday with 'Be The Change' theme
Gloucestershire Live online
2022-04-27
Three of the UK’s most exceptional nature writers: Marchelle Farrell, Nina Mingya Powles and Tjawanga Dema share their advocacy for the planet through art. Energy efficiency and policy expert David Glew and materials scientist Mark Miodownik discuss how to make our homes and gardens more eco-friendly and reduce our carbon footprint, while conservation scientist Adam Hart leads a panel about gardening to save the planet and there’s a litter-picking walk around Cheltenham.
How to lower your bills with a better grasp of home energy use
The Conversation online
2022-03-03
The future does not look bright for energy bills, with fuel poverty set to affect over 6 million UK households in 2022. And industry consensus appears to be that prices currently squeezing homes and businesses will not come down any time soon.
Event Appearances (1)
Unintended Consequences of Internal Wall Insulation; Increased Risk of Mould Growth for Uninsulated Neighbours
1st International Conference on Moisture in Buildings (ICMB21) UCL London
2021-06-28
Articles (5)
Barriers to domestic retrofit quality: Are failures in retrofit standards a failure of retrofit standards?
Indoor and Built Environment2021 Thermal retrofits of homes are central to the UK's fuel poverty and net zero carbon policies but there are concerns about poor quality installation and so new standards are to be introduced (PAS2035). We have explored retrofit installers' perceptions of the barriers to installing internal wall insulation (IWI) and of current regulations and standards for retrofits. We conducted four focus groups with retrofit installers. Thematic analysis identified three themes. (1) IWI is viewed as impractical in situations other than new builds, extensions and conversions as it is too time-consuming and expensive. (2) Installing IWI is perceived as an unskilled job with no need for training or referring to standards during installation. (3) Because standards lack credibility, installers can be sceptical of potential problems caused by on-site installation adaptations, for example thermal bridging. Our results show that retrofit standards have not improved retrofit quality. Awareness and credibility of standards is low, and new standards (PAS2035) will introduce additional costs which may reduce the pool of installers willing to engage in the retrofit market. Policies need to address installer training, professional identity and social practices, and reduce barriers to change in order to increase success.
A modified approach to metabolic rate determination for thermal comfort prediction during high metabolic rate activities
Building and Environment2020 Environmental conditions in buildings are linked to the physical and mental wellbeing of occupants. Thus, it follows that the internal environment affects human performance and user experience during sport and activity. There are several indices that are used to evaluate occupant thermal comfort, the Predicted Mean Vote (PMV) index being the metric most commonly used. PMV is designed to evaluate comfort for sedentary occupants with low metabolic rates; however, PMV has also been used to evaluate comfort for individuals engaged in high metabolic rate activities, such as those common in sport facilities. This paper investigates the implication of using PMV to evaluate thermal comfort in sport facilities using empirical data recorded over 24 months in a multi-purpose sports hall in the North of England. Data are used to develop and propose methodological modifications to improve the standard PMV model prediction to account for occupants having higher metabolic rates. The paper evaluates the use of metabolic rate data from different sources including the Compendium of Physical Activities and quantifies the impact that the metabolic weighting approach has on predicted comfort. Finally, a novel method is proposed to modify PMV for use where occupants have high metabolic rates. Despite the improvements made, the findings suggest that even a modified PMV may not be able to accurately evaluate the thermal comfort of people engaged in non-sedentary activity, recommending that use of the PMV index is restricted to activities with metabolic rates
Retrofitting suspended timber ground-floors; comparing aggregated and disaggregated evaluation methods
Building Research & Information2020 It is estimated that around 80% of UK dwellings have uninsulated ground floors, representing a significant heat loss mechanism in these buildings. In this research, an aggregated assessment of dwelling heat loss was made using the electric coheating test before and after a ground floor retrofit took place. Heat loss was reduced by 24% (43 ± 18 W/K) indicating that suspended timber ground floor retrofits could improve thermal comfort for occupants and contribute to government domestic energy efficiency policy targets. The findings indicate that disaggregated evaluation methods, such as spot heat flux density measurements, may overestimate the benefits of fabric retrofits. Aggregate methods may therefore be more appropriate tools with which to evaluate retrofits. The U-value improvement resulting from the suspended timber ground floor insulation retrofit, derived via aggregate measurement, was 0.55 W/m²K. Disaggregated spot heat flux density measurements indicated the improvement was 0.89 W/m2K. This research also indicates that Energy Performance Certificates, are unlikely to provide a reliable estimate of energy savings, because they rely on default assumptions for fabric U-Values and ventilation rates. This has implications for policy evaluations as well as householders, who may be excluded from financial support for retrofits.
An analysis of errors in the Energy Performance certificate database
Energy Policy2019 Energy Performance Certificates (EPCs) are the adopted method by which the UK government tracks the progress of its domestic energy efficiency policies. Over 15 million EPCs have been lodged, representing a valuable resource for research into the UK building stock. However, the EPC record has a reputation of containing multiple errors. In this work, we identify many such errors and quantify how common they are. We find that 27% of EPCs in the open EPC record display at least one flag to suggests it is incorrect and estimate the true error rate of the EPC record to be between 36 and 62%. Many of these errors are caused by EPC assessors disagreeing on building parameters such as floor type, wall type and built form. Additionally, flats and maisonettes appear to cause more issues than other property types. This may be due to difficulties in assessing their location in the building and the nature of the surrounding space. We also suggest potential new methods of quality assurance which rely on machine learning and which could allow such errors to be avoided in the future.
Assessing the equity and effectiveness of the GB energy price caps using smart meter data
Energy Policy2019 Keeping homes at a comfortable temperature and reducing household fuel bills are priorities for many governments. In the UK, several interventions have been implemented to achieve these objectives. This paper investigates one such policy lever - the Energy Price Cap - to understand if it has been designed and implemented efficiently and equitably. The price cap was introduced for customers on prepayment meters to combat increased levels of fuel poverty and a lack of competition in this group. However, the price cap was based on several assumptions of how energy is used. In this work, we assess how well the price cap accounts for real energy use using smart meter data. Households on economy 7 (EC7) tariffs were found to spend more than those on standard rate tariffs, as EC7 customers use more electricity during peak hours than assumed in government calculations. Additionally, many of the EC7 customers in this sample still use a considerable amount of gas, suggesting the EC7 heating product is either not sufficient, or is not being utilised in a cost-effective manner. Revisions to the input assumptions in government models for EC7 customers would therefore be beneficial in future price cap levels.
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