Hydrogen in General Aviation for an efficient and sustainable future

Abstract

As global climate change accelerates, the aviation sector faces increased urgency to reduce carbon emissions in pursuit of the global goal of Net Zero 2050. Hydrogen has emerged as a promising fuel for future green aviation, offering high energy density per unit mass and virtually zero carbon dioxide emissions. The study examines two major pathways of hydrogen implementation in general aviation: combustion in piston engines and hydrogen fuel cells. Within combustion systems, both spark-ignited and compression-ignited (by using a kerosene jet) engines are analyzed, their pros and cons. The challenges they encounter are also addressed, including premature ignition, NOx emissions, and backfiring. Hydrogen fuel cells are evaluated efficiency across varying load conditions and operating temperatures, cooling systems, and long-life spans. At the same time, major drawbacks, including weight, storage limitations, and design complexity, are also accounted for. Hydrogen use in internal combustion chambers shows a practical short-term solution as it has a high technology readiness level and requires minimal modifications to existing engines. On the contrary, Hydrogen fuel cells hold the most promising future, but are hindered by current technological barriers. The study presents a detailed comparison chart between internal combustion engines (ICE) and Hydrogen fuel cells, including efficiencies, emissions and complexity. Finally, the study concludes the importance of hydrogen in green aviation, while highlighting the need for infrastructure development and innovations in hydrogen storage.