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Research and Development in Novel Alternative Renewable Energy Technology Research and Development in Novel Alternative Renewable Energy Technology Zheming Wen A thesis is submitted in partial fulfilment of the requirements of Bournemouth University for the degree of Doctor of Philosophy October 2015 Faculty of Science and Technology Bournemouth University This copy of the thesis has been supplied on condition that anyone who consults it is understood to recognise that its copyright rests with its author and that no quotation from the thesis and no information derived from it may be published without the author's consent. ii Abstract Fossil fuels have become the main energy source for human after the Industrial Revolution. However, with ever-increasing energy consumption, they are not sustainable in terms of their finite reserves, pollutions to the environment and contributions to climate change. Driven by these problems, the EU and UK have together set a mutual objective to generate renewable energy as 20% of the total energy supply by 2020. This research project, fully funded by Future Energy Source Ltd, is a direct response to the needs of developing novel alternative renewable energy technologies. This project concerns about the research and development of a large scale flat plate solar collector (LSFPSC) with serpentine tubing that can be fully integrated into building envelops. The project work focuses on design improvements for increasing thermal performance, enhancing reliability and minimising costs of the LSFPSC. This is accomplished by employing a three-stage approach combining both experimental testing and simulation studies. An experimental facility was designed and built for testing the LSFPSC prototype with comprehensive monitoring equipment for collecting important data such as temperature and flow rates. The 1st stage experimental results and mathematical analyses showed that the unglazed LSFPSC prototype has an operating efficiency of 28.55%. In the 2nd stage, research was done to propose suitable improvements which were then tested experimentally. These improvements include changing the heat transfer mechanism between the absorber and the circulation system, enhancing the bond conductivity and minimising convective losses. The improved prototype showed increased operating efficiencies of 43.50% (unglazed configuration) and 46.07% (glazed configuration). In the 3rd stage, the experimental and analysis data from the 2nd stage were employed to design TRNSYS simulation that was used to simulate the LSFPSC’s performance using weather data from 36 different locations in 22 countries. The simulation results showed the LSFPSC is capable of producing mean useful output of 1.29 GJ/m2/year (glazed) and 1.00 GJ/m2/year (unglazed). Further economic evaluation showed the LSFPSC has much shorter payback period (2.4 to 6.5 years) than the typical commercial flat plate collectors (8 to 12 years) indicating that the LSFPSC is an economical solution for low/medium temperature applications. i List of Publications Journal Publications 1. Wen Z., Khan Z., Camfield, T., 2015. Experimental study of a large scale flat plate solar collector with continuous serpentine tubing configuration for building integration. Energy for Sustainable Development (Submitted) 2. Wen Z., Khan Z., Camfield, T., 2015. Simulation study of a large scale flat plate solar collector with continuous serpentine tubing configuration and building envelope integration for domestic hot water pre-heating and space heating. Solar Energy (Submitted) Abstracts in Conference Proceedings 3. Khan Z., Wen Z., 2014. An Experimental Study of a Novel Solar-Thermal System for Domestic and Commercial Applications. ASME 2014 International Mechanical Engineering Congress. 14th – 20th November 2014, Montreal, Canada. 4. Wen Z., Khan Z., Camfield T., Hadfield, M., 2014. Research and Development in Novel Alternative Renewable Energy Technology. 6th University Annual PG Conference 22nd – 23rd January 2014, Bournemouth University Poster Conferences 5. Wen Z., Khan Z., Camfield T., Hadfield, M., 2013. Research and Development in Novel Alternative Renewable Energy Technology. Prize Winner of the 6th PGR Poster Conference, 22nd May 2013, School of Design Engineering and Computing, Bournemouth University. 6. Wen Z., Khan Z., Camfield T., Hadfield, M., 2014. Research and Development in Novel Alternative Renewable Energy Technology. Prize Winner of the 6th University Annual PG Conference 22nd – 23rd January 2014, Bournemouth University 7. Wen Z., Khan Z., Camfield T., Hadfield, M., 2014. Efficiency Enhancement through Thermal Optimisation and Materials Design for a Novel Renewable Energy Technology. 7th PGR Poster Conference, 21st May 2014, School of Design Engineering and Computing, Bournemouth University. ii Table of Contents ABSTRACT ........................................................................................................................... I LIST OF PUBLICATIONS..................................................................................................... II Journal Publications ........................................................................................................ii Abstracts in Conference Proceedings .............................................................................ii Poster Conferences ........................................................................................................ii LIST OF FIGURES .............................................................................................................. VI LIST OF TABLES ................................................................................................................ IX NOMENCLATURE .............................................................................................................. XI ACKNOWLEDGEMENTS .................................................................................................. XIII AUTHOR’S DECLARATION ............................................................................................ XIV CHAPTER 1 ......................................................................................................................... 1 1. Introduction .................................................................................................................... 1 1.1 A Brief History of Energy Use in Human Society ...................................................... 1 1.2 Current Energy Problems ......................................................................................... 2 1.3 Alternative Energy Sources ...................................................................................... 4 1.4 Current Solar Industry .............................................................................................. 5 1.5 Potentials of Building-Integrated Solar Heating Systems .......................................... 7 1.6 Motivation for Work .................................................................................................. 8 1.7 Research Question .................................................................................................. 8 1.8 Aims and Objectives ................................................................................................ 8 1.9 Novelty ..................................................................................................................... 9 1.10 Thesis Outline ........................................................................................................ 9 CHAPTER 2 ....................................................................................................................... 11 2. Literature Review ......................................................................................................... 11 2.1 An Introduction to Solar Energy.............................................................................. 11 2.2 Solar Technologies Overview ................................................................................. 13 2.3 Solar Water Heating Systems ................................................................................ 18 2.4 Designs of Flat-Plate Collectors ............................................................................. 24 2.5 Building-Integrated Solar Heat Collectors ............................................................... 29 2.6 Mathematical Analysis ........................................................................................... 34 2.7 Scope of Research................................................................................................. 41 CHAPTER 3 ....................................................................................................................... 42 3. Methodology ................................................................................................................ 42 3.1 Research and Development Plan ........................................................................... 42 iii 3.2 Experimental Design .............................................................................................. 43 CHAPTER 4 ....................................................................................................................... 54 4. 1st Stage – Preliminary Experiments and Analyses ...................................................... 54 4.1 Experiment Scenario Design .................................................................................. 54 4.2 Energy Balance of Solar Collector .......................................................................... 55 4.3 Energy Input..........................................................................................................
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