Why Hydrogen-Powered Planes Will Beat Electric Planes

I love how aviation is always talked about so heavily but the useless cruise ship industry is never mentioned. One ship burning “bunker oil” is equivalent pollution to 5 million cars per day but I guess that’s okay?…

I'd like to see a similar report for the future of shipping and sea transport.

Former USAF flight surgeon and undergrad chemistry major here. Hydrogen has a very low energy density per volume and must be stored under immense pressure and/or low temperatures in order to have adequate energy to power anything other than very short flights. That requires very heavy, very expensive alloys. The very tiny molecule hydrogen literally seeps into metals and other materials causing “hydrogen embrittlement” and accelerating material fatigue. Extremely low temperatures make all materials less malleable and more prone to sudden, catastrophic fracture. Metals are bad, but plastics and other polymers can be even worse at low temperatures. Maintaining the necessary low temperatures adds even more weight and energy expenditure not directed to flight. Air pressure decreases with altitude magnifying the material stresses even more. The repeated ascents and descents under such immense pressure changes induce accelerated material fatigue. Temperatures also drop precipitously at altitude. H2 fuel cells and their platinum or iridium catalysts do very poorly at low temperatures. Direct combustion is more plausible, but H2 is incredibly explosive if a leak develops. Shut-off valves work well with liquid jet fuel, but much less well with gaseous H2 under immense pressure. All of the fuel lines and valves must be able to withstand all of the radical changes in pressure and temperature as well as the bulk H2 storage tanks. All of this adds immensely to weight which in turn stresses the non-fuel portions of the airframe and reduces flight efficiencies. We perform non-destructive stress damage analysis on current planes. This would needed to be performed even more sedulously on hydrogen planes. More delays and costs. Hydrogen-powered ships—yes; hydrogen-powered planes—I respectfully have my reservations. I hope they prove me wrong, but I heard none of these issues addressed to any significant degree. I am willing to be persuaded. Best wishes.

4:25 Great idea, show a random graph while talking about "airbus looking into hydrogen over time", I guess they were -25% looking into it in October 2022, whatever that means...

I'd like to see a documentary like this that includes some explanation of fuel storage and transportation 'why' and 'how' -- including descriptions of storage container weight, materials and construction; compression and cooling equipment design and costs (up-front capital, O&M, energy (kWh) required to run it), and; transport and storage compression pressures -- in order to help viewers understand why a fuel with, "...the highest energy per mass of any fuel..." has to be compressed to 13,000 psi or cryogenically cooled before it's useful in an aircraft, car or truck. This would help viewers appreciate what it actually takes to achieve and sustain 13,000 psi or minus 425F, and the challenges created by such pressures and temperatures during transporting and storage as compared to traditional liquid fuels.

While H2 is energy dense by mass, by volume it leaves much to be desired. H2 also needs to be either cryogenically frozen or highly pressurized in storage which drags on its round trip efficiency. H2 could still play a big role in green ammonia production, which has greater energy density by volume without the previously mentioned problems of h2. The holy grail in my view would be developing a scalable and cheap direct ammonia fuel cell (vs having to crack the ammonia back to H2, which again, drags on efficiency).

That is not a ATR-72 !! Thats a dash 8 !!

No matter if the medium is battery, hydrogen, or whatever; it is only a medium. We need a massive increase in non-fossil electricity capacity to power all of these vehicles, and it needs to start now because it is going to take a while to get there. This needs to be addressed.

HYDROGEN being the smallest atom in the universe is EXTREMELY hard to store because it just leaks from containers, that and the fact that hydrogen is also extremely flammable which means every leak has the potential for disaster.

In a way, even hydrocarbon is some kind of battery. Plants absorb the energy from the sun and convert it to carbohydrate as energy storage. When the plant died they got buried deep overtime. The fibrous part was petrified, and the carbohydrate was refined by pressure and heat into hydrocarbon.

8:04 that’s a Dash 8 not an ATR

Hydrogen powered aircraft was investigated back in the 1970s. It wasn't economical back then for large aircraft and I doubt it will now. One of the drawbacks was storing large quantities of hydrogen at an airport.

Aviation is where hydrogen makes the most sense to start a hydrogen economy. Next would be replacing natural gas with hydrogen. Then hydrogen for trains, busses, trucks, and finally passenger cars. Hydrogen is a great way of storing and transmitting energy. There are however a number of technical, safety, and economic hurdles to overcome. Hydrogen can be produced from water and electricity. Renewable, nuclear, or even fossil fuels. Thus hydrogen could ultimately be not only the cleanest fuel, but also the cheapest fuel.

One thing is true, Hydrogen is potentially the best option. But thats when you just see in context on a fuel to engine. But when you see supply chain, whole big cargo planes , Hydrogen generation and transportation Then you realize its still in infancy stage.

CNBC does top-notch documentaries, interesting and well researched. Ammonia is really the key here...too bad there was no mention of it (though this doc was focused on H2)...NH3 is a better H2 carrier than liquid hydrogen....about twice as much and its in liquid form can be held at a much lower pressure about 10 bar (while H2 gas is at 700 bar)...that's the real future imo. Ofc NH3 is a toxic substance, so we'd need to handle it better than we do gasoline (as it can cause blindness), but for decarbonizing, it's the pinnacle for an alternate energy source.

cnbc contents are getting better by the day

Brilliant Coverage in Hydrogen usage in aircraft! Thank you for sharing this important topic in in aviation fuel alternatives. Greetings from Madang, Papua New Guinea!

Electric Trams are probably the ultimate form of green transport as the batteries are not carried on the vehicle itself but soo much focus is being placed on electric cars 🤷

I like the idea of a combination of two fuels: Catalytically derived, cellulosic or algae biobutanol for landings and takeoffs; Then a switchover to ammonia (NH⁴) for cruising. Might be the easy & quick low CO² fuel path. I think speed & 'anti-absolecence' is important to avoid the increase in CO² from the manufacturing of new aircraft right away.

Hydrogen isn’t just the lightest fuel, it’s the lightest element. There is no type of atom weighs less than an Hydrogen atom.