Life cycle assessment of a regional hybridelectric aeroplane

Abstract

This thesis presents a life cycle assessment (LCA) of a hybrid electric aeroplane based on the ES-30 currently under development by Heart Aerospace. The thesis and the LCA aim to answer the following questions: (i) How large are the environmental impacts of the hybrid-electric aeroplane?, (ii) Which part of the life cycle has the largest environmental impact?, (iii) Where are the largest uncertainties in the inventory data?, (iv) How would changes in the base-case assumptions alter the overall results of the study?, and (v) Are the environmental impacts different from those of a similar-sized aeroplane with a conventional propulsion system? The LCA is performed with a cradle-to-grave perspective where the life cycle is divided into production, use phase and end-of-life. The production is modelled with help from published literature, experts at Heart Aerospace and datasets from Ecoinvent 3.9.1. The use phase investigates different flight scenarios concerning flight distance, type of fuel and electricity mixes for charging. The end-of-life only includes dismantling and sorting of materials since the built-in cut-off approach in the Ecoinvent 3.9.1 database was used to conduct the LCA. The largest uncertainties lie in the aeroplane production since the actual ES-30 is still under development with changes being made to the design and material choices through the duration of this thesis. However, the results of the LCA indicate that the use phase is the dominating phase for all impact categories included in this study. Most of the impacts can be allocated to fuel production and combustion as well as the production and use of batteries. By changing the fuel to alternative aviation fuel, there are reduction potentials in mainly climate change impact and particulate matter formation. Although the future role of alternative aviation fuels is uncertain and may lead to negative impact in other impact categories. Still in the base case with fossil kerosene and Swedish electricity mix, the ES-30 is environmentally beneficial compared to a similar-sized conventional aeroplane. The one impact category where the ES-30 most probably will perform worse than a conventional reference aeroplane is mineral resource scarcity due to the use of rare metals for batteries and power electronics