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Uvic Thesis Template On the Modelling of Solar Radiation in Urban Environments – Applications of Geomatics and Climatology Towards Climate Action in Victoria by Christopher B. Krasowski B.Sc., University of Victoria, 2012 A Thesis Submitted in Partial Fulfillment of the Requirements for the Degree of MASTER OF SCIENCE in the Department of Geography Christopher B. Krasowski 2019 All rights reserved. This Thesis may not be reproduced in whole or in part, by photocopy or other means, without the permission of the author. ii On the Modelling of Solar Radiation in Urban Environments – Applications of Geomatics and Climatology Towards Climate Action by Christopher B. Krasowski B.Sc., University of Victoria, 2012 Supervisory Committee Dr. David E. Atkinson, Department of Geography Supervisor Dr. Johannes Feddema, Department of Geography Member iii Abstract Modelling solar radiation data at a high spatiotemporal resolution for an urban environment can inform many different applications related to climate action, such as urban agriculture, forest, building, and renewable energy studies. However, the complexity of urban form, vastness of city-wide coverage, and general dearth of climatological information pose unique challenges doing so. To address some climate action goals related to reducing building emissions in the City of Victoria, British Columbia, Canada, applied geomatics and climatology were used to model solar radiation data suitable for informing renewable energy feasibility studies, including photovoltaic system sizing, costing, carbon offsets, and financial payback. The research presents a comprehensive review of solar radiation attenuates, as well as methods of accounting for them, specifically in urban environments. A novel methodology is derived from the review and integrates existing models, data, and tools – those typically available to a local government. Using Light Detection and Ranging (LiDAR), a solar climatology, Esri’s ArcGIS Solar Analyst tool, and Python scripting, daily insolation (kWh/m2) maps are produced for the city of Victoria. Particular attention is paid to the derivation of daily diffuse fraction from atmospheric clearness indices, as well as LiDAR classification and generation of a Digital Surface Model (DSM). Novel and significant improvements in computation time are realized through parallel processing. Model results exhibit strong correlation with empirical data and support the use of Solar Analyst for urban solar assessments when great care is taken to accurately and consistently represent model inputs and outputs integrated in a methodological approach. iv Table of Contents Abstract .............................................................................................................................. iii Table of Contents ............................................................................................................... iv List of Tables .................................................................................................................... vii List of Figures .................................................................................................................. viii List of Equations ................................................................................................................. x Glossary ............................................................................................................................. xi Acknowledgments............................................................................................................. xii Dedication ........................................................................................................................ xiv Introduction ......................................................................................................................... 1 Chapter 1: Solar Radiation at the Earth Surface ................................................................. 5 Solar Energy.................................................................................................................... 5 The Sun ........................................................................................................................... 5 Structure ...................................................................................................................... 6 Cycle ........................................................................................................................... 8 Solar Radiation............................................................................................................ 8 Sun-Earth Geometry ..................................................................................................... 10 Eccentricity ............................................................................................................... 11 Obliquity ................................................................................................................... 12 Precession ................................................................................................................. 13 Combined Effects...................................................................................................... 14 Solar Cascade ................................................................................................................ 15 Concepts and Terminology ....................................................................................... 15 Top-of-Atmosphere (TOA) ....................................................................................... 18 Atmosphere ............................................................................................................... 19 Surfaces ..................................................................................................................... 25 Solar Energy Modelling ................................................................................................ 30 Approaches ............................................................................................................... 31 Chapter 2: Methodology, Methods, and Data ................................................................... 44 Methodology ................................................................................................................. 44 v Overview ..................................................................................................................44 Methods and Data ......................................................................................................... 47 Empirical Measurements .......................................................................................... 47 Surface ...................................................................................................................... 50 Atmosphere ............................................................................................................... 56 Solar Analyst ............................................................................................................. 64 Chapter 3: Results ............................................................................................................. 67 Surface .......................................................................................................................... 67 DSM .......................................................................................................................... 67 Atmosphere ................................................................................................................... 68 Annual Daily Clearness ............................................................................................ 68 Seasonal Daily Clearness .......................................................................................... 71 Annual Daily Diffuse Fraction – Standard Models .................................................. 73 Annual Daily Diffuse Fraction – Seasonal / Model-Specific ................................... 78 Solar Model ................................................................................................................... 86 Solar Analyst ............................................................................................................. 86 Solar Analyst (modelled) Vs. Measured (Study Sites) ............................................. 88 Chapter 4: Discussion ....................................................................................................... 91 LiDAR........................................................................................................................... 91 DSM .............................................................................................................................. 91 Atmospheric Clearness ................................................................................................. 92 Diffuse Fraction ............................................................................................................ 92 Solar Analyst ................................................................................................................. 93 Processing ..................................................................................................................... 94 Results ........................................................................................................................... 94 Climate Action .............................................................................................................
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