Comment on New fuel cell could enable electric aviation
Emi@ani.social 10 months ago
Is this better than just using hydrogen?
The trouble with hydrogen is that it is very hard to store. It’s a very small molecule that can easily slip through even the tiniest gaps. So you actually have to cool it down or put it under a lot of pressure. Usually the latter is favoured because it doesn’t require any energy to keep up. But it is more prone to breakage which can result in an explosion.
I think Norway ditched their hydrogen plans after a gas station exploded. Not in a Hindenburg way, “just” from the pressure.
Both Boeing and Airbus are working on H2 Tech for Planes.
Pressure is also bad for aviation since pressure vessels are usually heavy.
Where do you get the H2 from?
Electrolysis? Ideally from excess solar or nuclear.
Sufficient storage capacity to meet overnight needs is going to be a challenge; storage to meet seasonal production variation is impossible. To make solar feasible, we need to build out sufficient generation capacity to meet our needs in winter. Winter, with, perhaps, 9-hours of mostly overcast skies and low angles over the horizon.
Imagine the output of that same system in summer: 15 hours of high-angle daylight and mostly clear skies.
The solar economy needs absurdly massive electrical loads in summer that can be readily shed over winter. We may see fleets of factory ships, loaded with electrolysis equipment, plugging into grids on whichever side of the equator is currently experiencing summer.
Maybe one day but for now it’s just green washed big oil
At present, however, just 2 per cent of the 600 billion cubic metres of hydrogen manufactured each year around the world is produced by water electrolysis, while 98 per cent is produced from natural gas, with carbon dioxide as a by-product.
More than 90 per cent of this hydrogen is used as a building block for fertilisers or is consumed within the oil, refining and wider petrochemicals industry.
The technology plans for these fuel cells aren’t “for now”. They’re for a future where we’ve hopefully already decarbonized most of the electric grid, as doing so is way more important than decarbonizing aviation. Converting fleets of airplanes to electric is a long process that will probably not be started for a while yet while there are more important carbon emission sources to tackle (aviation is only 2-3% of the emissions right now).
Best case, but a lot of hydrogen is produced using fossil fuels by my understanding.
T156@lemmy.world 10 months ago
Depending on how they do it, not having to deal with hydrogen infrastructure might be nice, if they keep along with the plan to use refillable cartridges. Hydrogen is a bit more fiddly.
Although this seems much more reliant on humidity compared to a hydrogen fuel cell, which seems like a huge hole if the thing just won’t work if it’s a dry day/environment.
ToastedRavioli@midwest.social 10 months ago
Considering the long term goal for them is to have them in planes at 30k ft, im sure they are entirely designed with the idea of humidifying the air to an ideal point prior to it getting to the catalyst for the reaction