Aircraft retrofitted with hydrogen fuel cells could slash CO2 emissions from small planes — and potentially pave the way for hydrogen jets, new study shows.
The first hydrogen-powered planes are taking flight::undefined
I am no fan of Hydrogen as a fuel. At least not for cars. It takes more to make it and it can offer up as a fuel. All the proponents of hydrogen cars usually have ulterior motives.
BUT... I think that changes for the the aviation industry. The fact remains that batteries are incredibly heavy and expensive and they simply are not power-dense enough. Those are all issues for a car, but even more so for a vehicle that flies. Hydrogen could very well be a reasonable alternative for the aviation industry. Hydrogen isn't particularly "green" to produce now, but there have been advances to make it much more so in recent years. I could see that being the fuel of the future for planes.
Hydrogen would also work well for ships, trains, and to some extent trucks. Basically anywhere that requires long distance travel without infrastructure in between where batteries just don't have the range or power to weight ratio to reach - at least not efficiently. And hydrogen is also specifically better for things connecting to a central transport hub, where the hydrogen production and storage and refueling can be centralized to minimize the infrastructure buildup and maximize production and storage efficiency. These would include ports, airports, trainyards, warehouses, sufficiently large bus terminals, basically everything except cars. And as a bonus it doesn't require stripping the earth or rare metals, sometimes mined by slave and child labor.
There have also been a lot of recent developments in hydrogen production as well. When these technologies are made at scale it will make hydrogen a lot cheaper and more viable as an alternative
I definitely think hydrogen and batteries solve different problems, and we're going to need both. Batteries have lower energy waste when recharging, and can handle power fluctuations better, while hydrogen has a far higher energy density, and scales much better to large scale storage. In addition, hydrogen tanks don't wear out the same way as batteries after many empty-full cycles.
This makes hydrogen very good for large scale applications, where the power requirements don't fluctuate much.
Hydrogen has a whole host of problems of it's own. The absolute lack of infrastrucure is a massive, massive, massive hurdle, but if you limit that infrastructure to just large scale applications (like airports) then it becomes much less of a problem. Still hydrogen storage is extremely tricky simply because the gas is so tiny. On an atomic level, it is hard to keep it contained. That seems trivial, but is really isn't. But ultimately if hydrogen is just one part of a wider energy solution, then things can get worked out.
Hydrogen storage is definitely something we need to do more research on. Cooling as well turns out to be quite a bit more complex than for most other fluids because of the quantum effects that become relevant once you close in on the critical temperature (which is very relevant if you want to store liquid hydrogen). It's not only a problem that hydrogen escapes when diffusing through a container, but it usually degrades the material the container is made of in the process, reducing the life time of the containers.
We're currently looking into using various materials that can adsorb and desorb hydrogen in a controlled manner for large scale storage applications, that's one of the possible solutions to the fact that hydrogen can diffuse through pretty much anything.