Hydrogen works pretty well for aviation, though there are three main challenges they’re still working on: size, materals, and fuel source.
Hydrogen is nice and lightweight, but the tanks and plumbing take up a lot of space, which cuts into cargo volume, basically limiting the range if you want to take passengers with you.
The second issue is that fuel cells currently require quite a lot of platinum, and the PEM electrolysis also requires a lot of PGMs and rare metals like Iridium. The material scientists are working on this, and I figure if they can take the cobalt out of batteries, they can take the platinum out of fuel cells.
The question that comes up the most when talking about hydrogen is where the hydrogen itself comes from. Right now, it’s mostly made by steam methane reformation or similar fossil fuel processing, which is nearly as bad for the environment as burning the fossil fuel directly. But there are promising advances in renewable electrolysis (such as taking advantage of peak solar for “free” electricity) which are closing the gap between SMR and renewable H2. It’ll never be as cheap as jet fuel, but it’s at least economically feasible.
Hydrogen works pretty well for aviation, though there are three main challenges they’re still working on: size, materals, and fuel source.
Hydrogen is nice and lightweight, but the tanks and plumbing take up a lot of space, which cuts into cargo volume, basically limiting the range if you want to take passengers with you.
The second issue is that fuel cells currently require quite a lot of platinum, and the PEM electrolysis also requires a lot of PGMs and rare metals like Iridium. The material scientists are working on this, and I figure if they can take the cobalt out of batteries, they can take the platinum out of fuel cells.
The question that comes up the most when talking about hydrogen is where the hydrogen itself comes from. Right now, it’s mostly made by steam methane reformation or similar fossil fuel processing, which is nearly as bad for the environment as burning the fossil fuel directly. But there are promising advances in renewable electrolysis (such as taking advantage of peak solar for “free” electricity) which are closing the gap between SMR and renewable H2. It’ll never be as cheap as jet fuel, but it’s at least economically feasible.