Space Sustainability Engineering: Quantitative Tools and Methods for Space Applications

This research explores the use of sustainability tools for space activities through a case study comparing the cost and environmental impacts of the SpaceX Falcon 9 and Falcon Heavy systems. The Falcon 9 and Falcon Heavy are similar in design; however, the Falcon Heavy was the first rocket launch system to successfully utilize a reusable first-stage booster system. The methodology employed was an attributional hybrid-Life Cycle Assessment (LCA). Upstream and downstream inputs and impacts were accounted for via economic input-output and process-based methodologies. A cradle-to-use-scoped system boundary for the two SpaceX Falcon systems were evaluated on a per-kilogram-delivered-to-geosynchronous-orbit basis. Producer cost data was integrated into the LCA framework to provide a cursory Life Cycle Costing (LCC) producer cost impact category to compare with the LCA environmental impact potentials. Findings showed the combined economic and environmental benefits achieved by SpaceX through developing the Falcon Heavy reusable booster system significantly reduced all evaluated environmental and cost impacts when compared to the Falcon 9. By applying the simple principal of reuse, SpaceX was able to reduce the cost of launch to high orbit by over $6,000 per kilogram while reducing environmental impact potential averages by >40% below the Falcon 9 system. This case study demonstrates the benefit of quantitative sustainability tools to guide economically and environmentally beneficial design for space activities.