Soiling in Solar Energy Conversion Technologies: Assessment and Mitigation
Total Page：16
File Type：pdf, Size：1020Kb
Soiling in Solar Energy Conversion Technologies: Assessment and Mitigation Ricardo Filipe Carrão da Conceição Thesis submitted to the University of Évora in fulfilment of the requirements for the degree of Doctor in Mechatronics Engineering andEnergy with specialiazation in Energy Supervisor Hugo Manuel Gonçalves Silva Supervisor Manuel Pedro Ivens Collares Pereira April 14, 2019 INSTITUTO DE INVESTIGAÇÃO E FORMAÇÃO AVANÇADA UNIVERSIDADE DE ÉVORA Science and Technology School Physics Department Soiling in Solar Energy Conversion Tech- nologies: Assessment and Mitigation Ricardo Filipe Carrão da Conceição Supervisors Hugo Manuel Gonçalves Silva Manuel Pedro Ivens Collares Pereira Mechatronics Engineering and Energy Thesis April 14, 2019 Jury President: Doctor João Manuel Gouveia Figueiredo, Associated Professor with Agregation, University of Évora, Portugal. Members: Doctor Eduardo Lorenzo, Full Professor, Polytechnic University of Madrid, Spain; Doctor Ahmed Alami Merrouni, Assistant Professor, Research Institute for Solar Energy and New Energies, Morroco; Doctor Miguel Centeno Brito, Assistant Professor, University of Lisbon, Portugal; Doctor Teresa Cunha Diamantino, Assistant Researcher, National Laboratory of Engineering and Geology – Laboratory of Materials and Coatings, Portugal; Doctor Hugo Manuel Gonçalves da Silva, Principal Researcher, University of Évora, Portugal. ”As a human being, one has been endowed with just enough intelligence to be able to see clearly how utterly inadequate that intelligence is when confronted with what exists.” Albert Einstein, Letter to Queen Elisabeth of Belgium, September 1932. Acknowledgments It has been a long journey until we finally got here. Yes, it is ”we” not ”I” since the mere existence of this thesis is only possible due to the help and incredible support, mostly during the difficult times, of my family and friends. I wish to thank from the bottom of my heart to my mother (Maria), my sister (Vera), my girlfriend (Catarina), my nephews (Francisco e Carminho) and my grandmothers (Angelica e Clotilde), for being my pillars during the elaboration of the thesis, but also my for being the pillars of my life. I am deeply grateful to my adviser, Professor Hugo Silva, which i consider a very good friend of mine. Always having new ideas, never giving up when the review of an article was not the expected and always cheering me up. I am also very thankful to Professor Hugo, since he was the one that gave me the chance to meet Professor Manuel Collares-Pereira and therefore engage in the Renewable Energies Chair. I am deeply grateful to my co-adviser, Professor Manuel Collares-Pereira, for giving me an opportunity and for believing in me and in my skills. He was an incredible support during my thesis work, helping me in so many ways, mainly in the papers. I also have to acknowledge all my co-workers, specially Francisco Tavares and Daniel Lopes. Special thanks to Professor José Mirão, from the Hercules laboratory, which allowed me to learn how to operate a Scanning Electron Microscope and also for his availability to perform measurements. I am also grateful to Anabela Rosado, from the Water laboratory, for teaching and let me use the spectrophotometer. I am very thankful to Professor Luis Narvarte, from the Universidad Politécnica de Madrid , for having me in the European project MASLOWATEN. A very special thanks to the University of Évora and the Institute of Earth Sciences, ICT (Instituto Ciências da Terra), which was my PhD scholarship host institution. This scholarship was attributed by the Portuguese Foundation for Science and Technology, FCT ( Fundação para a Ciência e Tecnologia ), without which this thesis could not be done and I have to express my sincere thanks. ix Contents List of Figures xv List of Tables xix Acronyms xxi Nomenclature xxiiii Abstract xxvii Resumo xxix 1 Introduction 1 1.1 Historical background . .1 1.2 State of the art . .7 1.3 Future perspectives . 13 1.4 Motivation and previous work . 14 1.5 Thesis structure . 14 2 Soiling measurements in rural environment for PV 17 2.1 Introduction . 17 2.2 Experiments and data . 19 2.2.1 Mass accumulation . 19 2.2.2 PV performance . 20 2.3 Annual Soiling Characterization . 22 2.4 Organic material characterization and features . 25 2.4.1 SEM characterization and image processing . 27 xi xii CONTENTS 2.5 Saharan Desert Dust Event . 29 2.5.1 Dust transport . 29 2.5.2 Dust chemical analysis . 31 2.5.3 Results . 33 2.5.3.1 Mass accumulation . 33 2.5.3.2 Photovoltaic performance . 34 2.5.4 Modeling . 35 2.6 Conclusions . 37 3 Soiling measurements in rural environments for CSP 39 3.1 Introduction . 39 3.2 Experimental campaign . 40 3.2.1 Measurements . 40 3.2.2 Soiling index . 41 3.2.3 Data Processing . 43 3.3 Soiling modeling . 45 3.3.1 Multiple linear regression . 45 3.3.2 Multiple linear regression of interaction terms . 46 3.3.3 Artificial Neural Networks . 49 3.3.4 Model comparison and discussion . 50 3.4 Portugal-Morocco soiling measurement campaign . 51 3.4.1 Results and Discussion . 52 3.4.2 Effect of long-range transport of Saharan desert dust . 53 3.4.3 Red rain effect . 54 3.5 Conclusions . 55 4 Soiling Mitigation for PV 57 4.1 Introduction . 57 4.2 Irradiance and soiling modeling . 59 4.2.1 Irradiance modeling . 59 4.2.2 Effective irradiance model with soiling . 60 4.2.3 Mass accumulation as function of the tilt angle . 61 4.2.4 Transmittance ratio as function of the tilt angle . 62 4.2.5 Angular loss coefficients . 63 4.2.6 Algorithm flowchart . 65 4.3 PV design including soiling effect . 66 4.3.1 Constant tilt angle configuration . 66 CONTENTS xiii 4.3.2 Multiple tilt angle configurations . 66 4.3.2.1 Trade-off between produced energy and configuration . 67 4.4Cleaning schedule modeling . 71 4.5Conclusions . 72 5 Soiling Mitigation for CSP 75 5.1 Introduction . 75 5.2 Methodology . 76 5.2.1 Coating production and development . 76 5.2.2 Measurement setup . 76 5.3 Results and discussion . 78 5.3.1 Experimental results . 78 5.4 SEM and image analysis . 81 5.5 Cost analysis . 82 5.6 Conclusions . 83 6 Conclusions 85 6.1 Conclusions . 85 A Multiple tilt angle configuration table 89 B Knowledge developed for the work in the thesis - 1 93 B.1 Introduction . 93 B.2 Methodology . 95 B.3 Results . 96 B.4 Discussion . 102 B.5 Conclusions . 104 C Knowledge developed for the work in the thesis - 2 107 C.1 Introduction . 107 C.2 Measurement campaign . 109 C.3 Desert Dust Transported into Southern Portugal . 111 C.4 Potential Gradient . 115 C.4.1 Daily analysis . 115 C.4.2 Robust lowess smoothing . 120 C.4.3 Wavelet analysis . 120 C.5 Dust charge model . 122 C.6 Conclusions . 126 List of Figures 1.1 Soiling studies evolution [1]. .2 1.2 Clarence Kemp’s Batch Solar Water Heater advertisement. .3 1.3 Archimedes feat representations: (a) Archimede’s mirror burning roman ships. Wall painting by Giulio Parigi, in 1600, at Uffizi Gallery, Florence; (b) Ceramic panel in the.