Hacker News Reader

The deal-killer with hydrogen in flight is specific energy storage.

At the moment, we have no hydrogen fuel storage technology that can even get a single-digit-percentage of a hydrocarbon fuel storage specific energy density.

Additionally, none of the current hydrogen storage tech is flight-worthy from an aviation systems management (weight, balance, on-boarding, jettisoning) and safety perspective.

View on HN

I'm not an expert, but from what I can find it looks to me like hydrogen has a higher specific energy (energy/mass) than gasoline, but a lower volumetric energy density (energy/volume).

https://en.wikipedia.org/wiki/Energy_density#Table_of_materi...

You're correct. The sentence, specifically ;) was referring to "specific energy storage".

We don't have ANY suitable hydrogen storage tech that's even envisioned, let alone prototyped or practical, that can compete with liquid hydrocarbons for flight.

The closest alternative is ammonia, but for reasons mentioned later in the discussion, ammonia combustion is a very poor match for aviation engines.

Reply on news.ycombinator.com