3 ms·
No. I don't buy it. You are asking me to believe that an accident or malfunction will NEVER occur (i.e., probability = 0) causing the hydrogen to leak in an env
by vivegi 3y ago
No. I don't buy it. You are asking me to believe that an accident or malfunction will NEVER occur (i.e., probability = 0) causing the hydrogen to leak in an environment containing air/oxygen (which makes an explosive mixture).
That compound failure mode (H + O_2 explosive mix upon structural failure/leak) doesn't exist with Helium. So, I respectfully disagree that the fears are outdated.
A survey of NASA's experience [1] is informative. From the linked article:
> Even small amounts of liquid hydrogen can be explosive when combined
with air, and only a small amount of energy is required to ignite it. Both its explosiveness and
the extremely low temperatures involved make handling it safely a challenge. It has taken a lot of
experience, including the experience of dramatic failures, to teach us just how dangerous it is and
how carefully we need to treat it.
[1]: https://www.nasa.gov/pdf/513855main_ASK_41s_explosive.pdf https://www.nasa.gov/pdf/513855main_ASK_41s_explosive.pdf
- comfypotato 3y agoLike I said, helium airships would be a necessary step to pave the way for hydrogen airships. Consider the eventual progress of the automobile to gasoline. Hydrogen is more dangerous than gasoline, but there are many similarities that can be drawn between the proposed use of hydrogen and the current use of gasoline (also extremely explosive). Earlier automobiles, before the advent of widespread gasoline adoption, showed how the investment into IC engines (including safety) was worthwhile. The prospective gain in the efficiency of global logistics is extremely significant. Airships, once we have established the infrastructure necessary for accommodating low-altitude wind-related challenges, effectively eliminate propulsion/fuel costs. They are sailboats unconstrained by the shape/locations of oceans, and wind patterns are reliable and predictable at altitude. Fully autonomous airships, needing human involvement only at ports, are entirely realistic. The marginal cost of global shipping, for goods where time isn’t a concern, is almost completely eliminated. Imagine airships for the purpose of relocating natural resources. Natural resources inherently need be relocated, and the time value is negligible. Airship ports could be engineered specifically to overcome the safety challenges. Autonomous airships make the marginal cost of natural resource distribution completely negligible. It’s entirely realistic to ship quantities via airship that reflect today’s largest container ships.