Liquid hydrogen has a lower energy density than jet fuel
The volumetric energy density of liquid hydrogen and jet fuel differs significantly due to their distinct physical properties and energy content. The volumetric energy density of liquid hydrogen is approximately 8 megajoules per liter (MJ/L).1 Liquid hydrogen has a high energy content per unit mass but a relatively low energy content per unit volume due to its low density. The volumetric energy density of Jet A-1, the type of jet fuel used in Boeing 737s for commercial flights, is approximately 35 MJ/L.2 Jet fuel has a much higher energy content per unit volume compared to liquid hydrogen due to its higher density. These values illustrate the key challenge in using hydrogen as an aviation fuel: while hydrogen offers high energy per unit mass, its lower volumetric energy density requires larger storage volumes compared to traditional jet fuel to achieve the same energy content.