this post was submitted on 17 Sep 2023
474 points (95.2% liked)
Technology
59679 readers
3266 users here now
This is a most excellent place for technology news and articles.
Our Rules
- Follow the lemmy.world rules.
- Only tech related content.
- Be excellent to each another!
- Mod approved content bots can post up to 10 articles per day.
- Threads asking for personal tech support may be deleted.
- Politics threads may be removed.
- No memes allowed as posts, OK to post as comments.
- Only approved bots from the list below, to ask if your bot can be added please contact us.
- Check for duplicates before posting, duplicates may be removed
Approved Bots
founded 1 year ago
MODERATORS
you are viewing a single comment's thread
view the rest of the comments
view the rest of the comments
One use case for hydrogen is sea amd aircraft. H2 has a very high power density. Sea abd aircrat can't use batteries because they woukd take all tge space for people and cargo.
It's more complicated than that. Hydrogen has a higher energy density than gasoline on a mass basis (i.e. 1 kg of hydrogen is about 3x the energy density of 1kg of gasoline). But for volumetric density the situation is reversed - 1Kg of hydrogen takes 4x the space of 1kg of gasoline. So you're not really saving anything by using hydrogen.
On top of that gasoline is a liquid at atmospheric pressures and can flow into any nook and cranny of your aircraft. Most aircraft will store fuel in the wings and under the fuselage. If you use hydrogen you have to store it in heavily reinforced pressurized tanks, preferably spheroidal, cylindrical, toiroidal in shape. That means you're looking at putting some honking great cylinders on your aircraft and there is no convenient place to do it. They'll either have to be mounted on struts or in the body somewhere.
I don't think batteries will find much application in aircraft until solid state batteries come along. But there are some high density batteries appearing for aviation applications (drones, taxis etc.) and just like with gasoline they can be incorporated pretty much anywhere in the structure of the aircraft.
even solid state batteries are not close enough to come close to what aircraft need. Also there are some way to store hydrogen in a liquid form that does not need pressure. Although then you have to have a water to mix with to make the h2 gas for the fuel cell.
I don't even know where to start with that.