QUANTITATIVE SUSTAINABILITY MODELING AND ASSESSMENT OF US TRANSPORTATION ENERGY SYSTEMS, INCLUDING CASE STUDIES OF ALTERNATE BIOFUEL PRODUCTION AND ORBITAL TRANSPORTATION SYSTEMS by Tyler M. Harris Copyright by Tyler M. Harris 2018 All Rights Reserved A thesis submitted to the Faculty and the Board of Trustees of the Colorado School of Mines in partial fulfillment of the requirements for the degree of Doctor of Philosophy (Civil and Environmental Engineering). Golden, Colorado July 25, 2018 Signed:____________________________ Tyler M. Harris Ph.D. Candidate Signed:____________________________ Dr. Amy E. Landis Thesis Advisor Golden, Colorado Date:__________ Signed:____________________________ Dr. Terri S. Hogue, Professor and Head Department of Civil and Environmental Engineering ii ABSTRACT This research identified and assessed the sustainability risks of existing and emerging US transportation energy systems using quantitative sustainability engineering methodologies including life cycle assessment (LCA) and growth curve modeling. A macro-level analysis of US energy and transportation system dynamics was performed to identify system level sustainability impacts and risks. Two case studies were explored with the aim of identifying where policy and technological solutions could improve sustainability: alternative biofuel production and orbital transportation systems. The findings demonstrated that logistic growth curve modeling fixed condition forecasts can be used to evaluate macro US energy and biofuel production systems. The macro-level assessment suggested the need for significant efforts to ensure the sustainable development of US energy and fuel production through 2040 with appropriate policy support employing such sustainability methodologies. Findings regarding alternate biofuel production demonstrated that biofuels cultivated on marginal lands could noticeably contribute to increased sustainable fuel production in the US. The environmental impact assessment results for biofuel cultivation on abandoned mine land showed the modeled land amelioration and biofuel production process produced significantly less environmental impact than other commonly employed reclamation processes. US biofuel policy would benefit from including such biofuel production on marginal lands in production goals. Furthermore, this research included the first LCA of orbital transportation systems including a proposed space elevator with comparison to existing terrestrial megaprojects. Results showed that the space elevator has the potential to be an environmentally- and cost-effective means for payload delivery to Earth’s orbits, and that reusable rocket launch infrastructure such as with the Falcon Heavy significantly reduced environmental and cost impacts. These quantitative sustainability models, assessment, and case studies revealed them to be a robust and versatile set of tools and that sustainable engineering can shed light on potential paths to a more sustainable future. iii TABLE OF CONTENTS ABSTRACT …………………………………………………………………………………….. iii LIST OF FIGURES ……………………………………………………………………………... ix LIST OF TABLES ……………………………………………………………………………… xii LIST OF SYMBOLS …………………………………………………………………………... xiv ACKNOWLEDGMENTS ……………………………………………………………………... xvi CHAPTER ONE INTRODUCTION ……………………………………………….. 1 1.1. Broader Impacts and Intellectual Merit ………………………….. 4 1.2. Research Background and Literature Review …………………… 6 1.2.1. Sustainability Engineering ……………………………………….. 6 1.2.1.1. Discussion on Modeling …………………………………………. 8 1.2.2. Life Cycle Assessment (LCA) ………………………………….. 10 1.2.2.1. ISO Process-LCA Methodology ………………………………... 10 1.2.2.2. EIO-LCA and Hybrid LCA …………………………………….. 12 1.2.3. Logistic Growth Curve Modeling ………………………………. 13 1.2.3.1. Development and Early History of the Logistic Equation ……… 15 1.2.3.2. Other Growth Curves …………………………………………… 19 1.2.3.3. Hubbert’s Peak and the Logistic Modeling of Energy Resources ……………………………………………………….. 26 1.2.4. US Energy & Biofuels Policy …………………………………... 29 1.2.4.1. Biofuels on Marginal Lands and Abandoned Mine Land (AML) …………………………………………………….. 33 1.2.5. Sustainability Through Space Resources ……………………….. 35 1.2.5.1. Space Elevator ………………………………………………….. 37 1.3. References ………………………………………………………. 42 iv CHAPTER TWO LOGISTIC GROWTH CURVE MODELING OF US ENERGY PRODUCTION AND CONSUMPTION …………… 54 2.1. Introduction ……………………………………………………... 55 2.1.1. Logistic Growth Curve Modeling ………………………………. 57 2.1.2. Environmental Implications …………………………………….. 59 2.2. Material and Methods …………………………………………... 60 2.2.1. US Energy Production and Consumption Data ………………… 60 2.2.2. Logistic Growth Curve …………………………………………. 62 2.2.2.1. S-Shaped Logistic Equation …………………………………….. 62 2.2.2.2. Bell-Shaped Logistic Equation …………………………………. 63 2.2.3. Multi-Cycle Logistic Growth Modeling ………………………... 63 2.3. Results and Discussion …………………………………………. 66 2.3.1. Individual US Fossil Fuel Production Source Models ………….. 66 2.3.1.1. Individual US Renewable Energy Production Source Models …. 74 2.3.1.2. Individual US Nuclear Energy Production Model ……………… 76 2.3.1.3. Individual Total US Energy Consumption Model ……………… 77 2.3.1.4. Aggregate US Energy Production Models ……………………… 85 2.3.1.5. Total US Energy Production Aggregate and Total Consumption Models. …………………………………………... 89 2.4. Conclusions ……………………………………………………... 92 2.5. References ……………………………………………………… 94 CHAPTER THREE LOGISTIC GROWTH CURVE MODELING OF US BIOFUEL PRODUCTION ……………………………………. 100 3.1. Introduction ……………………………………………………. 101 3.1.1. Logistic Modeling Background ……………………………….. 101 3.1.2. US Renewable Fuel Standards ………………………………… 103 v 3.2. Methodology and Data ………………………………………… 104 3.3. Results and Discussion ………………………………………... 106 3.3.1. Abridged Logistic Models …………………………………….. 112 3.4. Conclusions and Policy Implications ………………………….. 114 3.5. References ……………………………………………………... 116 CHAPTER FOUR LIFE CYCLE ASSESSMENT OF SUNFLOWER CULTIVATION ON ABANDONED MINE LAND FOR BIODIESEL PRODUCTION …………………………… 122 4.1. Introduction ……………………………………………………. 123 4.2. Material and methods ………………………………………….. 128 4.3. Life Cycle Inventory (LCI) ……………………………………. 131 4.3.1. Land amelioration ……………………………………………... 132 4.3.2. Seed preparation ………………………………………………..133 4.3.3. Excluded agricultural processes ……………………………….. 133 4.3.4. Pest control ……………………………………………………..134 4.3.5. Agricultural production ………………………………………... 135 4.3.6. Biodiesel production …………………………………………... 136 4.3.6.1. Sunflower and biodiesel coproducts …………………………... 137 4.3.7. Refuse excavation and transportation (alternate scenario) ……. 137 4.3.8. Regulatory review ……………………………………………... 138 4.4. Results and discussion ………………………………………… 139 4.4.1. Transportation analysis ………………………………………... 140 4.4.2. Impact normalization and comparison ………………………… 143 4.4.3. Allocation of bauxite residue ………………………………….. 145 4.4.4. Energy outlook and yield sensitivity analysis …………………. 145 4.4.5. Mather coal mine refuse pile reclamation activities …………... 147 vi 4.5. Conclusion …………………………………………………….. 149 4.6. References ……………………………………………………... 149 CHAPTER FIVE SUNFLOWER CULTIVATION ON COAL MINE REFUSE PILES IN APPALACHIA FOR DIESEL BIOFUEL PRODUCTION FROM A LIFE-CYCLE PERSPECTIVE………………………………………………... 155 5.1. Introduction ……………………………………………………. 157 5.2. Methods ………………………………………………………...158 5.2.1. Goal, Scope, Functional Unit, and System Boundary ………… 159 5.2.2. Inventory, Impact Assessment, and Interpretation ……………. 160 5.3. Life Cycle Inventory (LCI) ……………………………………. 160 5.3.1. Geographic Information Systems (GIS) ………………………. 164 5.4. Results and Discussion/Interpretation ………………………….165 5.5. References ……………………………………………………... 168 CHAPTER SIX LIFE CYCLE ASSESSMENT OF PROPOSED SPACE ELEVATOR DESIGNS ……………………………… 168 6.1. Introduction ……………………………………………………. 170 6.2. Materials and methods ………………………………………… 173 6.2.1. Goal and Scope ………………………………………………... 176 6.2.2. System Boundary and Functional Unit ………………………... 176 6.2.3. Life cycle inventory (LCI) …………………………………….. 178 6.2.4. Life cycle impact assessment (LCIA) …………………………. 182 6.2.4.1. Uncertainty Analysis …………………………………………... 182 6.3. Results and discussion ………………………………………… 184 6.3.1. Capacity Utilization Sensitivity Analysis ……………………... 187 6.4. Conclusions …………………………………………………… 189 6.5. References ……………………………………………………... 190 vii CHAPTER SEVEN ENVIRONMENTAL AND COST LIFE CYCLE ASSESSMENT OF ORBITAL TRANSPORTATION SYSTEMS INCLUDING MEGAPROJECT INFRASTRUCTURE COMPARISONS ……………………… 193 7.1. Introduction ……………………………………………………. 194 7.1.1. Orbital Transportation Systems Overview ……………………..197 7.2. Methods ……………………………………………………….. 200 7.2.1. System Boundaries ……………………………………………..201 7.2.2. Life cycle inventory (LCI) …………………………………….. 202 7.2.2.1. Space Elevator ………………………………………………… 205 7.2.2.2. Falcon 9, Falcon Heavy, & Delta IV Heavy …………………... 206 7.2.2.3. Megaproject Infrastructure Systems …………………………... 206 7.2.3. Life cycle impact assessment (LCIA) …………………………. 208 7.2.3.1. Uncertainty Analysis …………………………………………... 208 7.3. Results and Discussion ………………………………………... 210 7.4. References …………………………………………………….. 215 CHAPTER EIGHT CONCLUSION ……………………………………………….. 217 8.1. Future Work …………………………………………………… 219 APPENDIX A CHAPTER 2 SUPPORTING MATERIAL …………………… 221 APPENDIX B EXTENDED CONFERENCE ABSTRACT ………………….. 228 APPENDIX C CHAPTER SEVEN COMIC PERMISSIONS ………………... 233 APPENDIX D LUNAR LIFE CYCLE IMPACT ASSESSMENT CATEGORIZATION AND CHARACTERIZATION, WITH LUNAR MINING LIFE CYCLE ASSESSMENT EXAMPLE …………………………………... 234 viii LIST OF FIGURES