Novel retrofit technologies incorporating silica aerogel for lower energy buildings

This thesis was submitted for the degree of Doctor of Engineering and was awarded by Brunel University.The aim of this Engineering Doctorate is to design, build and test novel environmental retrofit technologies to reduce energy consumption in existing buildings. Three contributions to knowledge are documented. The first contribution is the technical verification of a novel proof-of-principle prototype incorporating translucent silica aerogel granules to improve the thermal performance of existing windows without blocking out all of the useful natural light. The study demonstrates that a 10 mm thick prototype panel can reduce heat loss by 80 %, without detrimental reductions in light transmission. Payback periods of 3.5-9.5 years are predicted if applied as openable shutters or removable secondary glazing. The second contribution is a streamlined life cycle assessment of silica aerogel following the ISO 14000 standards. The study assesses the raw materials and electricity use associated with two of the three known methods of aerogel production. Despite being produced in a laboratory that had not been refined for mass manufacture, the production energy and CO2 burden from aerogel production can be recovered within 0-2 years when applied in a glazing application. The third contribution is the development and verification of a novel solar air heater incorporating granular aerogel, retrofitted to an external south facing wall, preheating the air in a mechanical ventilation system with heat recovery on a hard-to-treat domestic property. During the 7-day in-situ test, peak outlet temperatures up to 45 °C were observed and validated to within 5 % of predictions, preheating the dwelling’s fresh air supply up to 30 °C, facilitating internal temperatures of 21-22 °C without auxiliary heating. The predicted financial and CO2 payback for a range of cover thicknesses is 7-13 years and 0-1 years, respectively. Efficiency up to 60 % and a financial payback of 4.5 years is predicted with an optimised design incorporating a 10 mm thick granular aerogel cover.Engineering and Physical Sciences Research Council (EPSRC) and Buro Happold Ltd

Shadows and Cracks

Work reported herein was conducted at the Artificial Intelligence Laboratory, a Massachusetts Institute of Technology research program supported by the Advanced Research Projects Agency of the Department of Defense, and was monitored by the Office of Naval Research under Contract Number N00014-70-A-0362-0002.The VIRGIN program will interpret pictures of crack and shadow free scenes by labelling them according to the Clowes/Huffman formalism. This paper indicates methods of extending the program to include cracks and shadows and shows that such an extension makes available heuristics which allow the program to be less simple minded.MIT Artificial Intelligence Laborator

What Corners Look Like

Work reported herein was conducted at the Artificial Intelligence Laboratory, a Massachusetts Institute of Technology research program supported by the Advanced Research Projects Agency of the Department of Defense and monitored by the Office of Naval Research under Contract Number N00014-70-A-0362-0002.An algorithm is presented which provides a way of telling what a given trihedral corner will look like if viewed from a particular angle. The resulting picture is a junction of two or more lines each labelled according to Huffman's convention. Possible extensions of the algorithm are discussed.MIT Artificial Intelligence Laboratory Vision Group Department of Defense Advanced Research Projects Agenc

Predicted and in situ performance of a solar air collector incorporating a translucent granular aerogel cover

This is the post-print version of the Article. The official published version can be accessed from the link below - Copyright @ 2012 ElsevierThere is an opportunity to improve the efficiency of flat plate solar air collectors by replacing their conventional glass covers with lightweight polycarbonate panels filled with high performance aerogel insulation. The in situ performance of a 5.4m2 solar air collector containing granular aerogel is simulated and tested. The collector is incorporated into the external insulation of a mechanically ventilated end terrace house, recently refurbished in London, UK. During the 7 day test period, peak outlet temperatures up to 45 °C are observed. Resultant supply and internal air temperatures peak at 25–30 and 21–22 °C respectively. Peak efficiencies of 22–36% are calculated based on the proposed design across a range of cover types. Measured outlet temperatures are validated to within 5% of their predicted values. Estimated outputs range from 118 to 166 kWh/m2/year for collectors with different thickness granular aerogel covers, compared to 110 kWh/m2/year for a single glazed collector, 140 k h/m2/year for a double glazed collector and 202 kWh/m2/year for a collector incorporating high performance monolithic aerogel. Payback periods of 9–16 years are calculated across all cover types. An efficiency up to 60% and a payback period as low as 4.5 years is possible with an optimised collector incorporating a 10 mm thick granular aerogel cover.This work is supported by the EPSRC, Brunel University, Buro Happold Ltd. and the Technology Strategy Board

A Review of the Regulatory Energy Performance Gap and Its Underlying Causes in Non-domestic Buildings

This paper reviews the discrepancy between predicted and measured energy use in non-domestic buildings in a UK context with outlook to global studies. It explains differences between energy performance quantification and classifies this energy performance gap as a difference between compliance and performance modeling with measured energy use. Literary sources are reviewed in order to signify the magnitude between predicted and measured energy use, which is found to deviate by +34% with a SD of 55% based on 62 buildings. It proceeds in describing the underlying causes for the performance gap, existent in all stages of the building life cycle, and identifies the dominant factors to be related to specification uncertainty in modeling, occupant behavior, and poor operational practices having an estimated effect of 20–60, 10–80, and 15–80% on energy use, respectively. Other factors that have a high impact are related to establishing the energy performance target, such as early design decisions, heuristic uncertainty in modeling, and occupant behavior. Finally, action measures and feedback processes in order to reduce the performance gap are discussed, indicating the need for energy in-use legislation, insight into design stage models, accessible energy data, and expansion of research efforts toward building performance in-use in relation to predicted performance

Evaluation of a library of FDA-approved drugs for their ability to potentiate antibiotics against multidrug resistant Gram-negative pathogens

The Prestwick library was screened for antibacterial activity or 'antibiotic-resistance breaking' (ARB) potential against four species of Gram-negative pathogens. Discounting known antibacterials, the screen identified very few ARB hits, which were strain/drug specific. These ARB hits included antimetabolites (zidovudine, floxuridine, didanosine, gemcitabine), anthracyclines (daunorubicin, mitoxantrone, epirubicin) and psychoactive drugs (gabapentin, fluspirilene, oxethazaine). This suggests that there are few approved drugs which could be directly repositioned as adjunct-antibacterials and these will need robust testing to validate efficacy. [Abstract copyright: © Crown copyright 2019.

Innovative financing models for low carbon transitions: Exploring the case for revolving funds for domestic energy efficiency programmes

The IEA has estimated that over the next four decades US$31 trillion will be required to promote energy efficiency in buildings. However, the opportunities to make such investments are often constrained, particularly in contexts of austerity. We consider the potential of revolving funds as an innovative financing mechanism that could reduce investment requirements and enhance investment impacts by recovering and reinvesting some of the savings generated by early investments. Such funds have been created in various contexts, but there has never been a formal academic evaluation of their potential to contribute to low carbon transitions. To address this, we propose a generic revolving fund model and apply it using data on the costs and benefits of domestic sector retrofit in the UK. We find that a revolving fund could reduce the costs of domestic sector retrofit in the UK by 26%, or £9 billion, whilst also making such a scheme cost-neutral, albeit with significant up-front investments that would only pay for themselves over an extended period of time. We conclude that revolving funds could enable countries with limited resources to invest more heavily and more effectively in low carbon development, even in contexts of austerity

The fate of steroid estrogens: Partitioning during wastewater treatment and onto river sediments

This is the author's accepted manuscript. The final published article is available from the link below. Copyright @ 2010 Springer Science+Business Media B.V.The partitioning of steroid estrogens in wastewater treatment and receiving waters is likely to influence their discharge to, and persistence in, the environment. This study investigated the partitioning behaviour of steroid estrogens in both laboratory and field studies. Partitioning onto activated sludge from laboratory-scale Husmann units was rapid with equilibrium achieved after 1 h. Sorption isotherms and Kd values decreased in the order 17α-ethinyl estradiol > 17α-estradiol > estrone > estriol without a sorption limit being achieved (1/n >1). Samples from a wastewater treatment works indicated no accumulation of steroid estrogens in solids from primary or secondary biological treatment, however, a range of steroid estrogens were identified in sediment samples from the River Thames. This would indicate that partitioning in the environment may play a role in the long-term fate of estrogens, with an indication that they will be recalcitrant in anaerobic conditions.EPSR

Simulations of the Static Friction Due to Adsorbed Molecules

The static friction between crystalline surfaces separated by a molecularly thin layer of adsorbed molecules is calculated using molecular dynamics simulations. These molecules naturally lead to a finite static friction that is consistent with macroscopic friction laws. Crystalline alignment, sliding direction, and the number of adsorbed molecules are not controlled in most experiments and are shown to have little effect on the friction. Temperature, molecular geometry and interaction potentials can have larger effects on friction. The observed trends in friction can be understood in terms of a simple hard sphere model.Comment: 13 pages, 13 figure

There is no market for new antibiotics: this allows an open approach to research and development

There is an increasingly urgent need for new antibiotics, yet there is a significant and persistent economic problem when it comes to developing such medicines. The problem stems from the perceived need for a “market” to drive commercial antibiotic development. In this article, we explore abandoning the market as a prerequisite for successful antibiotic research and development. Once one stops trying to fix a market model that has stopped functioning, one is free to carry out research and development (R&D) in ways that are more openly collaborative, a mechanism that has been demonstrably effective for the R&D underpinning the response to the COVID pandemic. New “open source” research models have great potential for the development of medicines for areas of public health where the traditional profit-driven model struggles to deliver. New financial initiatives, including major push/pull incentives, aimed at fixing the broken antibiotics market provide one possible means for funding an openly collaborative approach to drug development. We argue that now is therefore the time to evaluate, at scale, whether such methods can deliver new medicines through to patients, in a timely manner