A Comparison between Electric Aircraft and Hydrogen Aircraft to Achieve a Net-Zero Aviation Future

Abstract:
In the wake of rising concerns about global warming and climate change, countries have adopted various policies and passed several protocols in order to promote decarbonisation for a more sustainable future. To achieve a global decrease in CO2 emissions, it is inevitable to reduce the GHG emissions via aviation, which is a major source of emissions in the transportation sector. This paper compares two of the most popular technologies for decarbonising aircraft: electric propulsion and hydrogen fuel combustion. To understand the advantages and disadvantages of these two propulsion pathways, their performance in energy density, efficiency and flight emissions were discussed; the technical challenges of both were analysed; the lifecycle greenness of each was criticised. It was concluded that electric aircraft is greener and more efficient than hydrogen aircraft during flight. However, hydrogen fuel is more likely to power future commercial airliners, especially for long-range trips, due to its high energy content. A holistic transformation of electricity and hydrogen production towards using greener technologies is a prerequisite to decarbonise the aviation industry. Technical breakthroughs in battery energy density and controls of hydrogen combustion are expected in the next few decades to reach the net-zero emissions goal by 2050.