I thought maybe he hit the brakes a little too soon, before the wheel touched down. The flight she referred to that Robert took had an even scarier landing. 😵💫
@@GrooveTasticThang Whilst that may well be true - the left wheel was clearly locked for a significant time, per the smoke. Had it not been smoking, and the same swerve observed, then asymmetric thrust would certainly be a contender for the cause.
You always hear the gravimentric energy density quoted for hydrogen by itself. I'm glad she's talking about the tanks, but I'd love to see a breakdown that's more quantitative. Any of the real-world tanks I've been able to find bring the energy density down by 95% or more once you consider the mass of the tank needed to hold it. For example, a tank to hold 5kg of hydrogen weighs 92kg.
Don't think we have enough time. Everybody should be doing all they can. Why are we not harvesting from rivers with trains of floating Achilles funnel turbines. Why are factories, shops, offices not told to install solar or tutbines to contribute for self use. There is so much but Governments don't help.
@@stevee8698 Everybody doing all they can should not include people wasting time and effort on dead ends. That’s taking valuable time, effort and resources away from the things that might help.
Check out the new liquid hydrogen tanks form GTL. They can carry more than 70% of hydrogen by weight!! The main problem of liquid hydrogen is boil-off (0.5-5% loss per day), but since flights generally last for a few hours (not days or months), it is a negligible problem. You also have to add the weight of the fuel cells, but Hypoint have some really power dense versions.
@@jimj2683 I wouldn't call up to 5%/day neglegible. That's up to a quarter of the tank over a work week. Add to that the fact that hydrogen is a greenhouse gas, and it's definitely something to worry about. The biggest downside with liquid hydrogen is that you spend 30% of it's energy liquefying it (compared to 10% for compressed). The efficiency numbers for hydrogen don't make sense with compressed hydrogen, and LH2 makes it even worse.
As "energy dense" as hydrogen is you need to count the casings, tanks etc in that for an actual apples to apples comparison of power to weight ratios. Not anti hydrogen, just for realistic comparison parameters. We don't judge pure lithiums energy potential, we judge battery pack kWh density and should do similar with hydrogen systems.
For this reason I really hope they've gone for a liquid hydrogen solution with as much integrated tank structure and possible concentrated in one area as opposed to the wings.
Yup. To me talking about hydrogen "energy density" without counting the storage is just green washing. Its like talking about tailpipe emissions of ICE cars without counting the energy that goes into drilling, refining, and transport.
The problem is exacerbated further because a battery could be put anywhere in the fuselage, e.g. in the wings or underneath. They could even be a structural component. Whereas hydrogen tanks are by necessity big honking cylinders due to the gas they have to store under pressure. That means putting them in the fuselage or mounting them on pylons. Either way, it's not very practical.
@@Watch-0w1 That's not even being proposed as a solution to that problem. Ammonia would just be a way to more safely store and transport hydrogen, but it still has to be cracked into hydrogen and nitrogen and the hydrogen would still be the only thing loaded onto a vehicle for use as fuel.
I love her bit about storing fuel “including in the wings”! That’s where MOST is kept - and not only because it’s convenient, but because its mass is used to relieve the various bending moments across the span. If all the jet fuel was kept in the fuselage - and in the case of a 747 we are talking upwards of 150 tonnes for long range sectors the wing/fuselage attachments would be enormously strong and therefore heavy. The same issue with wing mounted engine pods is relieved by wing tanks. Interesting to find out how H2 copes !
Typically hydrogen tanks are cylindrical. Any shape that has a low surface-to-volume ratio is good for a hydrogen tank, be that compressed or liquified hydrogen, because it's the surface that needs to be reinforced to handle the pressure. AFAIK, conventional jet fuel tanks are kinda prism-shaped tanks that match the shape of the wing very closely. This isn't a good fit for hydrogen - that's not to say you couldn't put an array of small-diameter long cylindrical tanks in there, but that shape's not ideal in surface-to-volume terms. Depending on the design of the wing and tank, they could have a structural role, adding stiffness. I've seen proposals to put a large-diameter short cylindrical tank in the fuselage, which would be a better in terms of surface-to-volume ratio but would have other challenges.
@@gigabyte2248 Yes, Airbus and others show the rear of the fuselage filled with a single large cryogenic tank in conceptual renderings. Of course that's at the expense of cabin and cargo space, but the weight also replaces useful passenger and cargo load, so it "works".
As soon as you showed the plane and they said they are retrofitting it to be hydrogen-powered I thought "I bet the whole cabin is filled with tanks and fuel cells". And it is. I didn't hear a single word spoken about how they plan to actually integrate this technology into an airframe and still have passenger or cargo space. As an experiental aircraft, good on them, great job... I just dont see the path forwards to commercialization. External fuel tanks might help, but would only get them part of the way there. With hydrogen-powered cars, they typically weigh more than a battery-powered equivalent, and have less space for passengers and cargo. Often they have no truck or frunk at all. And maybe with flight, energy efficiency doesnt matter as much as with cars, but fuel cells also rely on exotic, expensive metals and they are also not forever but have to be reconditioned or replaced far more often than straight batteries would. I just dont see how its possible especially with retrofitting... Not without losing passenger AND cargo space. Both of which are typically maximized on commercial aircraft to help cover the expense of the fuel. How is an also expensive fuel (and regular fuel cell replacements) going to compete with less cargo and passenger space? It sure feels like by they time they have all of this solved, we will have lightweight, high energy density batteries that will recharge ultra quick.
@@t43562 No. They said their goal was to remove the batteries and replace them with more fuel cells and tanks. They are weight limited. But that also means there is no weight or area left for cargo or passengers. For recreation that's fine. But for commercial vehicles its frankly a mystery how they will make that work.
Almost every '"fact" in your post was wrong. Why not research the issues you raised prior to posting? Basically make some effort to know what you're droning on about.
How the tanks will be packaged in an existing airframe is certainly an interesting question, but I'm pretty sure they've thought about this. Maybe it'll be less than a 19seater when it's done, or maybe the tanks will actually fit in the wings. Energy efficiency certainly does matter, and weight matters critically, which is why using batteries only works for very short-range flights like the Vancouver Harbour Air Beavers. Hydrogen in carbon fibre tanks does weigh significantly less than batteries. I don't believe that fuel-cell maintenance is any more onerous than existing aviation engine maintenance. You have to check and rebuild regularly anyway - I'd be surprised if maintenance cost was meaningfully different for this powertrain from existing turboprops. Might be more, might be less. Maybe batteries will improve energy density enough to make this obsolete but no such batteries exist today outside labs. Fuel cost may prove to be an issue over electricity in the long run, but that's moot until a viable battery plane with competitive range/payload actually exists. Apparently we'll find out in only a few years. The Eviation Alice is the only competitor in this market so far (250nm, 9 passengers), and they reckon it might be working in 2027. We shall see. The point about zeroavia is that it's evolution not revolution, which is a lot more likely to get you a certified, useable, machine relatively quickly. They will get overtaken by complete new airframe designs in the long run, but some of those might decide to use zeroavia's power unit too.
Overall, expect fuel cell systems to be more lighter/energy dense than battery. Whether that is worth the loss in efficiency and add overall complexity and cost depends on the situation. For aviation, boating and long haul trucking hydrogen does make sense.
the modular electrolyzer is the bigger thing to me. sure getting short haul flights greener is better for everyone, but if we can do trucking or shipping with hydrogen will be great. especially if you can incorporate it into ships then they could make their own fuel while underway, in a renewable fashion. or at warehouses, depots, and rest areas you could produce fuels and be cleaner and better than fossil fuels.
@@thankyouforyourcompliance7386 Cargo ships use a surprisingly small amount of power for their size. They are really slow and take two weeks to a month to cross the Pacific. The largest are similar in horsepower to a jumbo jet, and the smaller ones don't use a lot more than two or three times the plane in the video. Solar panels would do nothing for a diesel ship and wouldn't power the ship by themselves, but might extend the range of theoretical future hydrogen fuel cell ships.
Producing fuel on-the-go is less effective than using the generated electricity to directly drive the motor, allowing you to consume less fuel. Vehicles - be they cars, lorries, ships or planes - normally consume much more energy than can be generated by a solar and/or wind array sized to fit on the vehicle. That's not to say on-board generation isn't worth looking into, but it would really only be suitable for offsetting some of the energy consumption, not solely powering the vehicle.
Hydrogen certainly has a place in the future of aviation but the main problem that these journalists seem to not understand is that hydrogen may have a high specific energy but it’s energy density is not very good which is more important to Aircraft designers. Yes, there is a major weight saving but that can quickly disappear when you have to introduce heavy insulated tanks, active cooling systems and a need to store it in the fuselage rather than the wings due to aeroelastic constraints. Therefore what is needed is a new approach to aircraft design rather than modification of existing designs.
With liquid jet fuel, the plane gets light as you use the fuel. You can also save weight by not filling up for shorter trips. With electric, the weight doesn't change unless you change out the batteries for smaller ones, but then you have to plan better weight distribution. The hydrogen, the weight doesn't change much because the hydrogen doesn't weigh much and you still have the weight from the tanks.
Jets are not interesting in this context. We're dealing with props. Electric engines are extremely efficient compared to combustion engines, and although this prototype just uses existing planes, future electric planes can use radically different designs, such as 50 small prop engines rather than two giant ones. But they have to start somewhere.
Curious how much hydrogen is lost to leaks in the system. Is it more difficult to keep atomic hydrogen contained compared to molecular gases? seems like that would be an added challenge in storing enough for long range flight
It's significant(in a scientific sense), but wouldn't be a big concern over < 10 hr flights. Will definitely need some interesting engineering for aviation usage. It's more of a concern for storage, which is why the tanks for hydrogen are so heavy compared to tanks for co2 or propane.
The biggest issue with any leaks isn't the loss of hydrogen, but hydrogen's very strong tendency to explode, violently, when mixed with air. Hydrogen have a very low minimum ignition energy, and very wide flammability range, and very wide explosive range, that, combined with the very high gravimetric energy density, much higher than any other combustion fuel, makes hydrogen mixed with air very likely to explode, and the explosions very intense.
Interesting question. Single atomic hydrogen doesn't exist, except for very brief moments in chemical reactions. H2 gas is problematic because it's the second smallest molecule after helium gas. This can be a safety feature out of doors in that the smaller and lighter gas molecules are, the faster they diffuse to a density that's too low to burn, but it's definitely not a safety feature when it's in an enclosed space like an aircraft hangar. I suspect hangars for hydrogen planes would need some serious ventilation near the top.
I’m not a scientist or engineer in any particular discipline. Like most folks, I’m genuinely curious and fascinated (and worried) about the old and current technologies we use for transportation. Granted there are significant challenges with low carbon technologies but I wonder if a fusion of fuel, electric and hydrogen power is initially a better option until the actual technology can be reliable developed to run transportation at a true zero carbon emissions standard.
Interesting you mention contrails very briefly. There are a lot of studies about these right now but it does seem aviation coild become a net cooler if we utilised contrails to our benifit, but it's not particularly fashionable to talk about
So a form of geoengineering essentially creating artificial clouds. Yes it will cool the planet, that what clouds do but it going to be bloody expensive to do and to produce those using something which doesn't cause a different of pollution.
@@DavidKnowles0 Yes but no. Contrails are being made without addition of any technology. Contrails are predictable in their formation as there is accurate weather forecasting in where they will be made. By flying at levels where they made in the daytime helps reflect the sun's energy back out to space, yet creating them at night traps the heat in. So if you fly at levels to create them in the day and avoid them at night you create an enormous benefit. Daytime formation may not be popular, people don't like contrails, but areas such as the North Atlantic or other oceanic tracks where nobody lives, or sparsely populated areas, or days where it's just cloudy at low levels are not a problem. We have the tech, it's being worked on, it's just not cool and exciting enough to make news
This is awesome, good to see we're trying to make hydrogen work. I really think this will win over batteries, just a matter of time. Not an easy job to make and store the stuff, but I imagine a future where gas stations will make their own hydrogen greenly and sell it to customers. The only emission will be the occasional solar panel replacement and some maintenance.
A simpler intial description of this proto-type is that there is a standard aviation fuel turbo prop on the starboard side,but a hydrogen fuel cell prop on the port side with a back-up pack of lithium iron batteries during trials.
Unfortunately many people that I come across don’t know the difference between port and starboard. Yes, saying port and starboard is more correct, but it doesn’t help if people don’t understand what either mean.
@@justinweatherford8129 Excellent point! And of course hydrogen fueled engines can only be used on the starboard side. Nobody knows why and is simply regarding as "being one of those things". The same way that we never, ever see the props being driven by giant rubber bands any more. In tests earlier this week the planes never got to the end of the runway, let alone into the air. An excellent safety feature, as I'm sure you'll all agree.
It seems there's still a long way to make it feasible for long haul flights but this could be great for shorter flight when speed and altitude are not an issue. Travel between small islands probably the best use case since other short routes are best covered by trains.
Even in the UK getting from city by train can take half a day as you need to change, even thought the distance is not that far. So much for upgrading the railways. These short haul planes can fill the bill. Pure EV planes even more so as they are _very_ quiet, so ideal over urban areas.
@@johnburns4017 It doesn't make sense between larger cities, trains have killed a lot of flights in European countries with high speed rail. Italy and France are good examples. But electric planes make a lot of sense for more rural towns, especially when there's already airfields. Norway has a bunch of these in the north, tiny airports for tiny towns. Widerøe is working with Tecnam and SAS is working with Heart to get electric planes on the shorter haul routes. SAS as a matter of fact just announced they will soon sell tickets for the first flights in 2028. 5 years away of course, but we are getting there!
@@dogjennings1171 Never say never, we can get breakthroughs in the future. But it makes sense to start with the shorter haul flights. Replace planes where trains can't replace them in a good way. But for a lot of Europe, high speed trains should be the goal. For more rural areas, smaller e-planes is a good idea.
Hydrogen is improving at a modest pace. Battery tech, EV motors, and solar seem to be improving faster and faster. Sort of how consumer electronics spawned the battery tech needed to make EVs viable for consumers, then commercial trucks, and so on, I can see this massive swing to EVs on the ground rub off onto aircrafts. The energy density needed with possible solar panels on the aircraft make full battery electric the way to go. It would be easier to build and maintain. Imagine airports no longer needing jet fuel services or hydrogen services. Just large battery storage and solar systems. Maybe battery swap for aircrafts will make sense, but considering the time it takes to load and unload crafts, maybe rapid charging will be all that is needed. Hearing this guy say 2035 for their aircrafts makes me think full battery electric aircrafts have a shot at becoming the new standard.
All of that except solar panels completely covering every inch of an airport wouldnt even charge up one small aircraft. You would need a very large wind farm or nuclear power plant nearby. I do think we are on the verge of seeing some very energy dense batteries, but they will be VERY expensive... so just like cars, big upfront cost, lower downstream costs in operations and maintence. But a fully electric airport feels very very very far away. I have doubts of seeing that within my own lifetime and Im only in my mid 40s. But I still think it will beat hydrogen.
@@patreekotime4578 I have seen solar tech that was spray on and solar tech capturing a wider range of the light spectrum. This makes me believe solar tech is moving forward. It will likely show up on EVs first. We have some niche builders using it now for limited range extension, but the ever advancing computer tech and demand for better solar might get us the solar tech the is able to be used on aircraft by 2035. I believe the next ten years will likely have more major changes to the world due to tech then the past fifty years. Just not sure governments and society will know how to deal with it all.
If you want to know about renewables and the future fully charged is the place to go, and this report is outstanding, thank you. For all the naysayers out there this shows what is possible with hydrogen fuel cell flight.
That was really cool to see some early footage of planes swapping to Hydrogen fuel, & I love that they're producing green energy on-site. Everything's in test mode currently, but I can totally see the future being even better
2:54 Bit of a weird discussion about energy density, given that (as the graph shows) aviation fuel has something like four times the _volumetric_ energy density of liquid hydrogen. Seems to me that's the factor you should be considering since the gravimetric energy density is ruined by the weight of the tanks __
@fullychargedshow One criticism I would like to point out when it comes to fuel cell-powered aircraft is that a lot of people haven't got their heads screwed on correctly about realistic efficiency versus power and very commonly assume that a 30%-40% efficient turbine powered aircraft would be less efficient than a fuel-cell powered one. In aviation, the opposite is true despite the conventional logic around hydrogen fuel cell cars and engines. However, in reality, that common 30-40% figure includes the *propulsive* efficiency, *which is largely independent of the drive-train type but dependent on the propeller and environmental conditions.* not just the thermal efficiency. For example a GE90 or Trent XWB (I am aware this plane is a turboprop but it still requires highly engineered turbines and the argument still stands on the power requirements anyway) is actually capable of above 50% thermal efficiency, but add on the 70% propulsive efficiency and you get the cliche'd 30-40% figures. Then add in the fact that aircraft turboprops and turbofans have power levels for those efficiencies FAR in excess of fuel cells, and the fact that many hydrogen drones exhibit fairly low efficiencies of roughly 30%, add in the extra motors needed, however lightweight they are, and one understands that there is no current realistic case optimal case for a non-combusting aircraft despite the 'futuristic' appearance of fuel cells. And then there's the durability reductions with electrochemical fuel cells. If the fuel cell paradigm was truly advantageous, contemporary aircraft and ships would be using hydrocarbon-consuming fuel cells. For the reasons above I would be skeptical of this company.
@@sneaky_krait7271 Downstream of the fuel cell innterms of both power and efficiency that is. I have no problem with the performance of electric motors, its just that the combustion turbine is more direct.
@@josephkolodziejski6882 I don't fully understand your point. Fuel cell has 60% efficiency and electric motor >90%. So combined about 55%, which is greater than all efficiencies you named, 30, 40 and 50% for the combustion motor.
@@sneaky_krait7271 The act of simply compressing the hydrogen into storage tanks on the aircraft destroys the efficiency of the entire hydrogen propulsion system, as it requires absolutely enormous amounts of energy.
@@PistonAvatarGuy Not a problem with compression. Electrochemical compression is capable of 85% compression efficiency and the energy can be recovered. The use of compression is what I don't like. Energy/weight is too low to be justified, might as well be batteries.
I would imagine in the future when these might be operating they would integrate these fuel cells into the leading edge of the wing, this should cool them fast and help prevent icing at the same time
Can't believe that 2050 is talking about Sustainable Fuels.... So still burning stuff!! Yet battery density should be 400% better in 2050 than it is now. Surly there has to be a future without burning fuels.?
@@SomeKidFromBritain If there are zero carbon solutions (and there are) then they should be the ones we use in majority. Of course as they said, SAF have a role to play for bigger planes and longer flights but the amount of carbon we have iin the atmosphere today is already a problem so we need to prioritize zero carbon solutions
@SomeKidFromBritain Carbon Neutral.... like burning Wood Pellets shipped in from Canadian Forests instead of coal..... It is sadly not the truth just because you put a name on it like Carbon Neutral... No more than it was the Truth yesterday that Boris Johnson had handed over EVERYTHING already.... When it's proved today that he was lying again...!!
Imogen! Great job at FLC North on this topic. May I repeat my question? When will Airlines see value parity for domestic routes? The FCL panel suggested we were already there…
Hydrogen is only as green as its source. It only exists (on Earth) in forms bonded to other materials, from which it must be freed in order to be used. Currently the cheapest material from which to get hydrogen is natural gas. So, todays hydrogen, at best, is only as green as natural gas. This is why, when you look behind the push for hydrogen as a fuel, you find the fossil fuel industry, since hydrogen can also be generated by processing other forms of petroleum, and even coal. The ONLY way for hydrogen to be green is for it to come from splitting water into hydrogen and oxygen, using energy from solar, wind, hydro, or geothermal. Currently that is inefficient, and therefor not cost competitive with fossil fuel derived hydrogen. (on edit) at 10:35 I see they are addressing this. Good on them.
At 4:46 she points to the left wing and says that "on this side, that's where we've got the 600 kilowatt hydrogen fuel cell system". That is not true; the left wing has a 600 kW electric *motor* system, and nothing related to hydrogen or the fuel cell system at all. The hydrogen fuel and the entire fuel cell system are in the fuselage, in the cabin area.
It might be possible to minimise battery capacity for aviation hydrogen power systems because unlike with surface transportation, the overwhelming majority of any given flight is at a constant, very specific power level. But it's still impossible to completely eliminate the batteries because of takeoff and landing. The thing that hydrogen proponents are very careful to downplay is the fact that any "hydrogen-powered" vehicle is really just a BEV with the addition of the weight, complexity and failure points of the hydrogen-fueled electricity generator. It is not possible to throttle fuel cells the way ICE or Electric motors MUST be throttled in normal use, so fuel cells are really just range extenders for what is otherwise a pure BEV vehicle.
4:56 - Pure gobbledygook. Turboprop engines have gearboxes which allow them to produce as much torque as would ever be desired by an aircraft designer, electric motors offer no advantage in this area.
@@Yada-nj2ig A) You misread my comment. I said that turbine engines have gearboxes, I didn't say that the electric motors in this aircraft have gearboxes. B) Efficiency is irrelevant in this context, as there are no electric motors that are capable of being as light and as powerful as the more powerful turbines engines that are in production. C) Electric motors are limited by the amount of heat that they can dissipate, so the amount of torque that they can produce is limited by the amount of heat that they can dissipate at a given rpm.
They didn't say so. And no, even liquid hydrogen (cryo-cooled) has a volumetric energy density of just 2.4 kWh/litre. 1 kg of hydrogen equates to 3 kg of kerosene. 1 litre of kerosene equates to 4 litres of liquid hydrogen. Roughly.
Without counting in the higher efficiency of an fuel cell electric drivetrain compared to gas turbines. I suppose, 1 litre of kerosene in a gas turbine gives you as much mechanical work (propeller movement) as 2 litres of liquid hydrogen with an fuel cell electric drivetrain.
could electrici ty be used for the initial take off and landing and then other fuels used for flying the plane (I am making the assumption that take off and landing are the most inefficient parts of a flight)
2:40 How will the density of batteries change? Iets be honest with each other in the last 20-30 years the density didn't change upwards whatsoever. Mr. Goodenough did us a wonderful favour with li-ion but that's where we at for the last 30 years. No the Tesla battery change didn't increase the density of the battery, a new design allowed more lithium-ion per battery. The fact that the battery density didn't change and it won't because you will start to upset the laws of physics - big boom - is the reason that this H solution is worked out.
@@Zarphag CATL says CATL says up to 500wh/kg. charge/discharge cycles are unknown. No real world implementation at the moment so at this point marketing fluff. Amprius is also in the race for a 500wh/kg cell but hey it charges like a iPhone on a 5 watt charger. My point is, lets see a commercial implementation instead of something in a BETA stage. Batteries are hard to keep stable while pumping up the wh/kg without the tendency to explode.
350 bar is about 5,000 psi. There are 700 bar composite hydrogen tanks, too. That's a lot of potential energy that can change to kinetic energy very quickly.
This is what effective prototyping and R&D look like. Messy demo units that are big, clunky and inefficient, using off-the-shelf components that aren't a great fit for the application, loaded alongside a backup and a backup-backup... but they work anyway. ZeroAvia have built it and flown it and proven that it works. We're very used to seeing mature commercial technology, which has had decades of refinement. This is the first, ugliest version of this technology and I wish ZeroAvia the best of luck with the next version, and the next version, and the next version.
Just as a general point, you need to get Bobby Llew to talk on GB News to correct them on their hopelessly out of date "facts" on EVs...! I imagine RL may well break out in hives at there mere thought of talking to GBN, but slather him up in E45 and I'm sure he'll survive.
I wonder if liquid hydrogen could improve things. While it is really, REALLY cold, it can be kept at atmospheric pressure. So no sturdy tanks. And it has more energy per cubic-meter. So more oomph in the same space. And theoretically, you could just pour it into the tank. (not sure if that is a smart idea) While it will just evaporate and be gone after a while, that is no problem, as the plane will run exactly on these vapors. If it is not boiling into a gas fast enough to feed the fuel-cell, you could even expand it in a turbine or something. there is a lot of energy in a liquid that turns into a gas spontaneously. (see also: liquid N2 motors) While liquefying H2 takes an arse-ton of energy, you might get it back in the re-gassification. And if you're really putting your energy into making inefficient H2, you can go on and liquefy it.
Liquefied hydrogen is roughly double the density of compressed hydrogen at 10,000 pounds per square inch but requires a refrigeration plant that will keep the hydrogen below 254°C. BMW made a car using liquid hydrogen which was a nightmare because if the temperature goes above -254° C a hydrogen will be getting to flare off when you cannot park it indoors.
@@colingenge9999 right. The BMW was a disaster and a laughing stock - I remember (fun fact: I live 20 minutes from BMW head-quarters in Germany). But aircrafts don't sit around all day and get fueled once per week like cars. They get fueled up to a specific amount as per flight-plan (plus reserves) and then used right away. During use, LH2 can basically not be wasted by boil off - we want the gas to run the fuel-cell. After landing, the tank is mostly empty. Upon which they get refueled and reused. Yes. Sometimes they get parked and de-tanking would mean an extra step. Maybe boil-off is acceptable over night. Maybe a ground-based chiller can be clamped on, to re-condense boil-off. Dunno. Invent something. Yes, there are planes which sit around most of the time. Cannot catch 'em all - after all. But I guess once we get the politicians to put the correct amount of taxes onto CO2 to reflect the damage done to our Commons, companies will be getting inventive in a hurry! Or we stay on the ground with our asses. We stopped using airplanes in 2018. It was fun, while it lasted. Good bye, cheap vacations in low wage countries with loads of sunshine... But we stood by it, even if it has cost us tears and money - literally.
That's not new. Most of the interest in hydrogen in aviation assumes the use of liquified hydrogen, not compressed gas. To be practical, liquified hydrogen is kept at moderate pressure (typically at pressures up to 850 kPa or ~123 psi in industial settings), not ambient pressure... requiring pressure vessels.
5kg of hydrogen would give you, with my calculations, less than 100kWh usable energy after the fuel cells. We have cars running on the roads now with batteries in the 200kWh range. Looks to me that battery electric aviation can fill quite a big niche here.
I think it's hilarious that the "artistic" pan down from the ceiling at 3:36 shows the natural gas fired heating system in the hanger. ZeroAvia is dedicated to reducing carbon emissions, but doesn't electrically (with heat pumps) heat their own facility.
Take the hydrogen, react it with captured CO2 and make methanol. Can be stored as a liquid at atmospheric pressure and at room temperature, unlike hydrogen. No need for special high pressure tanks, just put it in the wings like regular fuel. Maybe needs different seals or something but you could run your regular turboprop engine on it. Methanol is 1/3 the energy density of kerosene so long haul flights wouldn't work, but short hops of a couple of hours would work well.
Not gonna happen. You need either a massive volume of the stuff at low pressure, and that means a huge fuselage. Or you need a very cold well insulated tank, which would be very heavy for the amount of fuel you carry, or you need a thick walled high pressure tank, or you need one filled with metal hydride. All of those have an excessive weight penalty which makes them impractical. The Russians flew an H2 powered jet around 1960 using large tanks. NASA were flying a Beech model 19 with a cryogenic tank in the mid 1970s. And in fact the first jet engine was powered on the bench by hydrogen in 1938, but it was never the plan to take it into the air like that.. Not gonna happen anytime soon, in other words.
@@Watch-0w1 No, I am not anti-hydrogen, and I am not saying the same thing as people who are anti EV are saying at all. I'm pointing out that it is a pipe dream to imagine that this will power an airliner. It won't happen. Electric power is also not practical for long range aircraft. The only realistic solution within our grasp right now, or even in the foreseeable future. is to produce a carbon neutral liquid fuel. Hydrogen is also not a practical fuel for cars. It simply isn't.
@@Watch-0w1 That's a different question. Besides, I thought you were all for hydrogen? Given up so easily? Please do tell me how you would fly an airplane with 300 people aboard with H2 fuel. Go on.
I find zero emission short haul flight an interesting proposition as it could well make trains far less compelling as it removes most or all of the environmental edge they have. If you can fly intercity across a given country using fuel generated on site be it hydrogen or battery electric then you remove the need for investments such as HS2 with its massive costs and negative environmental impact.
It’s the physics of hydrogen that makes it an impossible fuel since compressed to 10,000 psi as in the Toyota Mirai it’s still seven times the volume of kerosene for the same energy content. The weight of those tanks is in excess of the weight of hydrogen within the tanks. To say nothing of how hydrogen attacks metal causing embrittlement. many people think it’s just a matter of the technology getting more developed, but it’s the nature of the hydrogen atom itself. That is the problem. People constantly discuss the energy density of hydrogen as being amazing with respect to weight, but weight is not the issue, it’s all about volume. Take any jet fuel powered aircraft and increase the volume of the tanks by 11 and tell me how much room you’ve got left. This is also to say nothing about the cost of hydrogen from electrolysis being about seven times the cost of kerosene. Hydrogen is so bad That it’s extremely obvious that it will never even beat out battery powered aircraft, making me believe that it is one of the ploys of the fossil fuel industry to promote hydrogen so that we will be distracted from other meaningful ways of providing fossil fuel free transportation.
You say that it is an "impossible fuel", then you illustrate the challenges with an example from the Toyota Mirai, which is a real production car running on it. Perhaps you should consult a dictionary to learn what "impossible" means...
@@brianb-p6586 In retrospect, perhaps the only thing you could argue about is my choice of the word “impossible”. What IS true is that it’s impossible to change the physical characteristics of the element Hydrogen which is where all the problems lie and which is the subject of my posting. I assume then that you agree with everything else I wrote about Hydrogen apart from my use of the word “impossible”. IMPRACTICAL or UNECONOMIC would have been better choices.
@colingenge9999 I agree that there are significant challenges to the use of hydrogen as fuel - especially in aircraft - and that they make it largely impractical and uneconomic. There probably will be some specific applications where it is a good solution, eventually.
@@brianb-p6586 There’s been a huge market for Hydrogen as a feedstock for fertilizers and metal production but problematically, it’s touted as some miracle fuel available free in water which inspires a huge delusional following for people who simply don’t remember their high school physics but the real problem comes from gov’ts who buy into it without understanding it’s downsides. Not knowing is actually a secret way to fund Big Oil profits and distract us from workable renewables. Similar to fusion which is mostly a distraction from getting on with a transition. The challenge for aircraft cannot be overstated when you consider its massive volume, 11 times that of kerosine which would require a volume equal to the fuselage be used to store it. Battery Electric aircraft are already working on a limited scale; that’s the future.
Should be possible. You don't feed the full 350 bars of hydrogen directly into the fuel cell anyway. Normally you use a device to lower the pressure, 'your' engine could replace that. It could increase efficiency, basically it reuses the energy that is used to compress the hydrogen in the first place. By the way, this consumes much energy, apart from electrolysis. I think the problem is the power to weigh racio of this type of engine. So you would need to use a lot of hydrogen in a certain period of time for any serious power, maybe more than the fuel cell needs.
... the hydrogen-electric, the fully-electric also. And, later - even purely magnetic engines, as well. Yes, to all that. Finally, in the future, (that is considered a future to this moment) the engines are purely magnetic (rotary-system based), (by that time will be called RMG's). Only collecting from the existing environment energy to run, and is also 100% pollution free, and the most-powerful flight power, ever. Presently, moving away from the fossil fuels to power the flight (irregardless the carbon issue or not) is a very good move. With an addition, that, in the future - it will be indeed revolutionized - not only the pilots, but even the passengers onboard (supervised by the PIC's) will be flying and assisting at it. Everyone onboard for a flight will be considered: a team member :).
Yellow hydrogen can be lower in terms of greenhouse gas emissions than green hydrogen, as nuclear reactors can use high temperature methods, such as high temperature electrolysis, thermal cracking or the sulphur-iodine cycle, which operate at higher efficiencies than regular electrolysis. Thermal cracking can technically be achieved via concentrating solar power, albeit at lower temperatures and lower efficiency.
@@showme360 in a turbofan (which is not in this video) the gas turbine engine drives the fan... and provides some thrust directly by its exhaust flow. I'm sure that's what you meant.
Bad spin, if you want to compare the energy density of hydrogen without the weight of the tank compared to batteries should you not leave the battery out and only weigh the electrons?
I've always been very anti-hydrogen for vehicles, BEV just make more sense. But when it comes to flying batteries really don't. If a plane is running at half capacity, you can just stick less hydrogen in it. But if its got a battery, unless you've got swappable ones, that battery is going to weigh the same with 10% charge or 100% charge. Plane's gain efficiency the further into the flight it goes as it uses fuel and gets lighter and lighter. A battery powered plane has to have the same efficiency at take of as it does at landing, and unless we get some fantastic new battery development, that just isn't practical.
If you stick less hydrogen in it the weight is almost the same, since most of the weight of the hydrogen fuel system is the tanks, not the hydrogen itself.
if it's 3 times as energy dense as electric in terms of weight as a complete system, it probably won't be worth it in a couple of years when battery energy density becomes twice as dense, meaning the loss of energy in making the hydrogen and marginal differences in power to weight will make it less viable unless they can get the containment of the hydrogen lighter
Really interesting topic such a pity about the script, for example feeling it necessary to point out that the plane is surrounded by air, and describing the hydrogen creation process as out "pops" the hydrogen. It would be good to see the same article aimed at adults.
Their biggest obstacle is economic. Hydrogen fuel cells are expensive, hydrogen storage is expensive, and hydrogen fuel is very expensive - with "green hydrogen" being even more expensive. It's hard for any commercial airliner to justify the cost and difficulty of switching to hydrogen when the fuel costs nearly double.
@@philipperapaccioli2868 Completely different design and 90 years of technological improvements, it like saying a steam train carriage is same to a passenger car as the both have wheels and can take passengers.
@@philipperapaccioli2868 I'm sure he was using sarcasm to illustrate the implication of the Hindenburg and other various hydrogen accidents. But the hydrogen wasn't the only problem with the Hindenburg, I believe the skin of the craft was flammable and once ignited by thousands of volts of built up static electricity the skin sparked between the frame and itself the gap between allowing the spark to ignite the hydrogen and kept on burning fr the plasticized covering that was doped over the cotton skin. Hydrogen fuel cell cars don't explode , so I doubt the hydrogen fuel cell airplane would either.
Except for full-sized airliners (e.g. 737 MAX and larger), hydrogen-fuel cell technology is "a fool's errand" - With exponential improvements with battery energy density and orders of magnitude improvements in aviation motor efficiency, ALL REGIONAL FLIGHTS will quickly change to all-electric planes, whether by replacing propulsion systems, or completely NEW aircrafts, which can take advantage of a "first-principles engineering" approach (vastly more efficient and easier to fly)
The killer when burning or using a fuel cell hydrogen be it a car, lorry and esp aircraft is the cost of it... at the best of time you looking at x4 the cost vs liquid fossil fuels which means a lot higher flying costs
Yes for ground vehicles. Even worse compared to bunker fuels used by container ships. But compared to aviation fuel its probably a wash. The replacement of fuel cells is expensive and problematic though.
Last time I checked, not very long ago, their fuel cell system had a maximum output of about 100 kW, to claim that the battery system is there for redundancy in providing power to the 600 kW motor is more than a stretch. The "hydrogen electric" side is basically a battery electric system with a hydrogen range extender, not a even good one, but a very bad one, very bad in multiple ways. The main problem with replacing fossil fuels is not lack of technically viable alternatives, it's the lack of economically viable options, because fossil fuels are extremely cheap to produce. Hydrogen is the fossil fuel industry's last big hope, as any resources intended for transition spent on hydrogen will make the period of business as usual longer, and if hydrogen reach wide use as a fuel in the foreseeable future, it will have to be produced from fossil fuels mostly, to be economically viable. One of the huge problems with fuel cells for aviation is their ridiculous power density, the higher power density you want the lower the efficiency you'll have to accept. This is still an issue for fuel cell cars, but they have managed to cram in acceptable powerful systems with kind of acceptable efficiency, with kind of acceptable space and weigh penalty, for passenger cars! Not anywhere near good enough to replace turbo props. Yes, you could put hydrogen tanks everywhere, but would you really want to? Just the pressure alone makes them more dangerous than jet fuel tanks, and if a tank bursts the hydrogen is very likely to explode, and make the other tanks burst and explode. For aviation combustion engines are totally superior to fuel cells. Sure, you create NOx, but assuming "clean" hydrogen, that's the only relevant drawback, and if only used in situations pure battery electric systems aren't viable, that's not much of an issue. Zeroavia lists water vapor and contrails as relevant issues, which they are not. They also claim fuel cells are far better than combustion in that regard, which makes absolutely no sense at all, the amount of water produced is determined by the amount of hydrogen that is used, which also dictates the amount of energy extracted. Sure, you can catch the water vapor from the fuel cell system, but if you wanted to you could du that with a piston engine powering a generator. Also, there would be about as much heat and exhaust from a fuel cell system as from a combustion engine at the same power output. Actually at very high power output for their size and weight, like almost comparable to aviation piston engines, current fuel cells would have much worse efficiency than a good piston engine, and therefor produce more heat and exhaust at same output of useful power. "Yeah, maybe so, but fuel cells are a new technology that catch up and surpass everything else!" Nope, they're not new, the first fuel cell was invented 185 years ago, which is well before the first rechargeable battery, well before the otto engine, and the diesel engine.
but they forget the bennefit of have a electical motor in the front wheel, for taxi to runway with lot less energy to activate extra range. perhaps a small electrical motor in each wheel, used for taxi, also have be used to rotate the wheel up to landing speed to avoid rummer burn duing landing, that will encrease the lifespan of the tires. and that will demand less rubber waste.
In the absence of suitable batteries today, hydrogen is being demonstrated here as a way to store electrical energy until technology is ready. Hydrogen per se has to be manufactured and stored, whereas electric supply is ubiquitous. This is an interim solution. CATL has already started producing cells rated at 500 Wh/kg. Doubling that figure (a fairly realistic objective) will enable aircraft designers to use batteries to power most new aircraft by the 2030s. Systems using hydrogen for electrical storage are very useful in developing the approach needed for large construction machinery and international shipping,
Hydrogen will only be becessary for long flights over seas, for short flights batteries are cheaper. An aluminium air battery can be used as emergency fuel used only if the hydrogen fuel tank gets empty leaks. Aluminium air battety is not chargable but it could be swappable and since it won't be used 99.99% of the time it will be just fine.
I'm interested in seeing if hydrogen is a viable secondary propulsion system for sail boats. They drag a propeller that generates electricity to charge batteries, why not hydrogen as well?
She should have said "propeller blades". This sort of obvious error not caught in review is typical of people writing or making videos about subjects in which they have little knowledge or familiarity.
Why don’t you guys say “if you have been, thank you for watching” anymore? Great video. Sounds like a very difficult task but I can see the “easiness” of producing H2 on site at airports at least…, so reduces all those issues with transporting it, distribution… 👍👍. It’s just such a hard fuel to keep within the tanks, no leaking…
The hydrogen contained in tanks provides twice the energy density of the batteries. Then there’s the weight of the fuel cell and everything to make the system work. It would be interesting to see an energy density comparison of a complete hydrogen system compared to a complete battery system. Battery density will probably double in a few years which would mean it’s simpler, and consequently cheaper, to provide the motors with electricity direct from batteries. While it’s good to see this innovation, the battery industry is working hard looking for ever more energy dense batteries. The hydrogen atom isn’t going to change its properties. There will be a point where batteries are a better option.
The problem is by 2035 battery tech and the energy density of them will have come leaps and bounds by then. There’s still plenty of infrastructure issues to resolve, but I can’t see a major hydrogen market coming to fruition.
I don't know how much water is required to make H2. But if H2 powered (anything), in this case, aviation, were to become common place, I wonder how much of an impact the increasing frequency and severity of droughts would have on (reliable) production and supply. TBC: I'm not trying to be an H2 naysayer here, merely wondering aloud.
Hydrogen is not exactly clean to make either. I still think they should try to upscale algae fuel. Algae absorbs CO2, has a high fat/oil content. It grows easily. So it may not reduce emissions but it should at least balance out. You can make aviation fuel from algae. It's just no one has been able to upscale it to mass produce fuel at current prices. Unless someone makes a dramatic breakthrough in battery tech that improves capacity and slashes weight. I think lots of options should be looked at.
Bit of a wild landing at 13:40 with a stuck left brake nearly taking them off the runway. The pilot earnt his pay.
Maybe the left hand experimental motor doesn’t have a fully functioning prop for reverse or beta ? Just a thought?.
I thought maybe he hit the brakes a little too soon, before the wheel touched down. The flight she referred to that Robert took had an even scarier landing. 😵💫
I agree, Thrust imbalance unlikely to clause that jerk, wind factor maybe, but more likely something to do with brakes
@@GrooveTasticThang Whilst that may well be true - the left wheel was clearly locked for a significant time, per the smoke. Had it not been smoking, and the same swerve observed, then asymmetric thrust would certainly be a contender for the cause.
You always hear the gravimentric energy density quoted for hydrogen by itself. I'm glad she's talking about the tanks, but I'd love to see a breakdown that's more quantitative. Any of the real-world tanks I've been able to find bring the energy density down by 95% or more once you consider the mass of the tank needed to hold it. For example, a tank to hold 5kg of hydrogen weighs 92kg.
Don't think we have enough time.
Everybody should be doing all they can.
Why are we not harvesting from rivers with trains of floating Achilles funnel turbines. Why are factories, shops, offices not told to install solar or tutbines to contribute for self use.
There is so much but Governments don't help.
@@stevee8698 Everybody doing all they can should not include people wasting time and effort on dead ends. That’s taking valuable time, effort and resources away from the things that might help.
Check out the new liquid hydrogen tanks form GTL. They can carry more than 70% of hydrogen by weight!! The main problem of liquid hydrogen is boil-off (0.5-5% loss per day), but since flights generally last for a few hours (not days or months), it is a negligible problem. You also have to add the weight of the fuel cells, but Hypoint have some really power dense versions.
@@jimj2683 I wouldn't call up to 5%/day neglegible. That's up to a quarter of the tank over a work week. Add to that the fact that hydrogen is a greenhouse gas, and it's definitely something to worry about. The biggest downside with liquid hydrogen is that you spend 30% of it's energy liquefying it (compared to 10% for compressed). The efficiency numbers for hydrogen don't make sense with compressed hydrogen, and LH2 makes it even worse.
@@stevee8698 true that.. we need multiple sustainable solutions.. if we want to live in a sustainable future.. not just one.
As "energy dense" as hydrogen is you need to count the casings, tanks etc in that for an actual apples to apples comparison of power to weight ratios.
Not anti hydrogen, just for realistic comparison parameters. We don't judge pure lithiums energy potential, we judge battery pack kWh density and should do similar with hydrogen systems.
They're is a solution already. Amoninian fluid, the cleaning stuff
For this reason I really hope they've gone for a liquid hydrogen solution with as much integrated tank structure and possible concentrated in one area as opposed to the wings.
Yup. To me talking about hydrogen "energy density" without counting the storage is just green washing. Its like talking about tailpipe emissions of ICE cars without counting the energy that goes into drilling, refining, and transport.
The problem is exacerbated further because a battery could be put anywhere in the fuselage, e.g. in the wings or underneath. They could even be a structural component. Whereas hydrogen tanks are by necessity big honking cylinders due to the gas they have to store under pressure. That means putting them in the fuselage or mounting them on pylons. Either way, it's not very practical.
@@Watch-0w1 That's not even being proposed as a solution to that problem. Ammonia would just be a way to more safely store and transport hydrogen, but it still has to be cracked into hydrogen and nitrogen and the hydrogen would still be the only thing loaded onto a vehicle for use as fuel.
I love her bit about storing fuel “including in the wings”! That’s where MOST is kept - and not only because it’s convenient, but because its mass is used to relieve the various bending moments across the span.
If all the jet fuel was kept in the fuselage - and in the case of a 747 we are talking upwards of 150 tonnes for long range sectors the wing/fuselage attachments would be enormously strong and therefore heavy. The same issue with wing mounted engine pods is relieved by wing tanks.
Interesting to find out how H2 copes !
(conservative estimate of fuel in large jets.... (B747-8 carries up to 194 tonnes of fuel) - I used to just throw around 200T.)
Of course this means the plane lands heavy.
@@PentaxAstro ??
Typically hydrogen tanks are cylindrical. Any shape that has a low surface-to-volume ratio is good for a hydrogen tank, be that compressed or liquified hydrogen, because it's the surface that needs to be reinforced to handle the pressure. AFAIK, conventional jet fuel tanks are kinda prism-shaped tanks that match the shape of the wing very closely. This isn't a good fit for hydrogen - that's not to say you couldn't put an array of small-diameter long cylindrical tanks in there, but that shape's not ideal in surface-to-volume terms. Depending on the design of the wing and tank, they could have a structural role, adding stiffness. I've seen proposals to put a large-diameter short cylindrical tank in the fuselage, which would be a better in terms of surface-to-volume ratio but would have other challenges.
@@gigabyte2248 Yes, Airbus and others show the rear of the fuselage filled with a single large cryogenic tank in conceptual renderings. Of course that's at the expense of cabin and cargo space, but the weight also replaces useful passenger and cargo load, so it "works".
Yeah I'd say hydrogen energy storage is a bit up in the air at the moment.
Plasma Kenetics offers a hydrogen storage solution which is ambient pressure and ambient temperature.
Boom tish.
As soon as you showed the plane and they said they are retrofitting it to be hydrogen-powered I thought "I bet the whole cabin is filled with tanks and fuel cells". And it is. I didn't hear a single word spoken about how they plan to actually integrate this technology into an airframe and still have passenger or cargo space. As an experiental aircraft, good on them, great job... I just dont see the path forwards to commercialization. External fuel tanks might help, but would only get them part of the way there.
With hydrogen-powered cars, they typically weigh more than a battery-powered equivalent, and have less space for passengers and cargo. Often they have no truck or frunk at all.
And maybe with flight, energy efficiency doesnt matter as much as with cars, but fuel cells also rely on exotic, expensive metals and they are also not forever but have to be reconditioned or replaced far more often than straight batteries would. I just dont see how its possible especially with retrofitting... Not without losing passenger AND cargo space. Both of which are typically maximized on commercial aircraft to help cover the expense of the fuel. How is an also expensive fuel (and regular fuel cell replacements) going to compete with less cargo and passenger space? It sure feels like by they time they have all of this solved, we will have lightweight, high energy density batteries that will recharge ultra quick.
... by chucking out the batteries.
@@t43562 No. They said their goal was to remove the batteries and replace them with more fuel cells and tanks. They are weight limited. But that also means there is no weight or area left for cargo or passengers. For recreation that's fine. But for commercial vehicles its frankly a mystery how they will make that work.
Almost every '"fact" in your post was wrong.
Why not research the issues you raised prior to posting?
Basically make some effort to know what you're droning on about.
How the tanks will be packaged in an existing airframe is certainly an interesting question, but I'm pretty sure they've thought about this. Maybe it'll be less than a 19seater when it's done, or maybe the tanks will actually fit in the wings. Energy efficiency certainly does matter, and weight matters critically, which is why using batteries only works for very short-range flights like the Vancouver Harbour Air Beavers. Hydrogen in carbon fibre tanks does weigh significantly less than batteries. I don't believe that fuel-cell maintenance is any more onerous than existing aviation engine maintenance. You have to check and rebuild regularly anyway - I'd be surprised if maintenance cost was meaningfully different for this powertrain from existing turboprops. Might be more, might be less.
Maybe batteries will improve energy density enough to make this obsolete but no such batteries exist today outside labs. Fuel cost may prove to be an issue over electricity in the long run, but that's moot until a viable battery plane with competitive range/payload actually exists. Apparently we'll find out in only a few years. The Eviation Alice is the only competitor in this market so far (250nm, 9 passengers), and they reckon it might be working in 2027. We shall see.
The point about zeroavia is that it's evolution not revolution, which is a lot more likely to get you a certified, useable, machine relatively quickly. They will get overtaken by complete new airframe designs in the long run, but some of those might decide to use zeroavia's power unit too.
Overall, expect fuel cell systems to be more lighter/energy dense than battery. Whether that is worth the loss in efficiency and add overall complexity and cost depends on the situation. For aviation, boating and long haul trucking hydrogen does make sense.
the modular electrolyzer is the bigger thing to me. sure getting short haul flights greener is better for everyone, but if we can do trucking or shipping with hydrogen will be great. especially if you can incorporate it into ships then they could make their own fuel while underway, in a renewable fashion. or at warehouses, depots, and rest areas you could produce fuels and be cleaner and better than fossil fuels.
Those giant freighters do have a lot of potential space to put solar panels.
That will not work technologically for planes. Not enough information for ships but that doesn't mean it works.
@@jeffreyquinn3820but they also need a lot of power. Wonder why people have not do the maths.
@@thankyouforyourcompliance7386 Cargo ships use a surprisingly small amount of power for their size. They are really slow and take two weeks to a month to cross the Pacific. The largest are similar in horsepower to a jumbo jet, and the smaller ones don't use a lot more than two or three times the plane in the video. Solar panels would do nothing for a diesel ship and wouldn't power the ship by themselves, but might extend the range of theoretical future hydrogen fuel cell ships.
Producing fuel on-the-go is less effective than using the generated electricity to directly drive the motor, allowing you to consume less fuel. Vehicles - be they cars, lorries, ships or planes - normally consume much more energy than can be generated by a solar and/or wind array sized to fit on the vehicle. That's not to say on-board generation isn't worth looking into, but it would really only be suitable for offsetting some of the energy consumption, not solely powering the vehicle.
Keep these types of informative videos coming! Good quality, good content and excellently presented.
Hydrogen certainly has a place in the future of aviation but the main problem that these journalists seem to not understand is that hydrogen may have a high specific energy but it’s energy density is not very good which is more important to Aircraft designers. Yes, there is a major weight saving but that can quickly disappear when you have to introduce heavy insulated tanks, active cooling systems and a need to store it in the fuselage rather than the wings due to aeroelastic constraints. Therefore what is needed is a new approach to aircraft design rather than modification of existing designs.
Love your work, Imogen 👍
4:56 Turbine blades should be propeller blades
With liquid jet fuel, the plane gets light as you use the fuel. You can also save weight by not filling up for shorter trips. With electric, the weight doesn't change unless you change out the batteries for smaller ones, but then you have to plan better weight distribution. The hydrogen, the weight doesn't change much because the hydrogen doesn't weigh much and you still have the weight from the tanks.
Jets are not interesting in this context. We're dealing with props. Electric engines are extremely efficient compared to combustion engines, and although this prototype just uses existing planes, future electric planes can use radically different designs, such as 50 small prop engines rather than two giant ones. But they have to start somewhere.
Curious how much hydrogen is lost to leaks in the system. Is it more difficult to keep atomic hydrogen contained compared to molecular gases? seems like that would be an added challenge in storing enough for long range flight
It's significant(in a scientific sense), but wouldn't be a big concern over < 10 hr flights. Will definitely need some interesting engineering for aviation usage.
It's more of a concern for storage, which is why the tanks for hydrogen are so heavy compared to tanks for co2 or propane.
Have you seen the recent study from Princeton U and NOAA. Leaking hydrogen causes methane to linger and magnify greenhouse gases as much as 30 years,
The biggest issue with any leaks isn't the loss of hydrogen, but hydrogen's very strong tendency to explode, violently, when mixed with air. Hydrogen have a very low minimum ignition energy, and very wide flammability range, and very wide explosive range, that, combined with the very high gravimetric energy density, much higher than any other combustion fuel, makes hydrogen mixed with air very likely to explode, and the explosions very intense.
@@fishyerik would you say like a bomba ?
Interesting question. Single atomic hydrogen doesn't exist, except for very brief moments in chemical reactions. H2 gas is problematic because it's the second smallest molecule after helium gas. This can be a safety feature out of doors in that the smaller and lighter gas molecules are, the faster they diffuse to a density that's too low to burn, but it's definitely not a safety feature when it's in an enclosed space like an aircraft hangar. I suspect hangars for hydrogen planes would need some serious ventilation near the top.
I’m not a scientist or engineer in any particular discipline. Like most folks, I’m genuinely curious and fascinated (and worried) about the old and current technologies we use for transportation. Granted there are significant challenges with low carbon technologies but I wonder if a fusion of fuel, electric and hydrogen power is initially a better option until the actual technology can be reliable developed to run transportation at a true zero carbon emissions standard.
Interesting you mention contrails very briefly. There are a lot of studies about these right now but it does seem aviation coild become a net cooler if we utilised contrails to our benifit, but it's not particularly fashionable to talk about
So a form of geoengineering essentially creating artificial clouds. Yes it will cool the planet, that what clouds do but it going to be bloody expensive to do and to produce those using something which doesn't cause a different of pollution.
@@DavidKnowles0 Yes but no. Contrails are being made without addition of any technology. Contrails are predictable in their formation as there is accurate weather forecasting in where they will be made. By flying at levels where they made in the daytime helps reflect the sun's energy back out to space, yet creating them at night traps the heat in. So if you fly at levels to create them in the day and avoid them at night you create an enormous benefit.
Daytime formation may not be popular, people don't like contrails, but areas such as the North Atlantic or other oceanic tracks where nobody lives, or sparsely populated areas, or days where it's just cloudy at low levels are not a problem.
We have the tech, it's being worked on, it's just not cool and exciting enough to make news
This is awesome, good to see we're trying to make hydrogen work. I really think this will win over batteries, just a matter of time. Not an easy job to make and store the stuff, but I imagine a future where gas stations will make their own hydrogen greenly and sell it to customers. The only emission will be the occasional solar panel replacement and some maintenance.
An excellent presentation - fascinating to know what is going on with aviation. Thank you.
A simpler intial description of this proto-type is that there is a standard aviation fuel turbo prop on the starboard side,but a hydrogen fuel cell prop on the port side with a back-up pack of lithium iron batteries during trials.
Unfortunately many people that I come across don’t know the difference between port and starboard. Yes, saying port and starboard is more correct, but it doesn’t help if people don’t understand what either mean.
@@justinweatherford8129
Excellent point!
And of course hydrogen fueled engines can only be used on the starboard side.
Nobody knows why and is simply regarding as "being one of those things".
The same way that we never, ever see the props being driven by giant rubber bands any more.
In tests earlier this week the planes never got to the end of the runway, let alone into the air.
An excellent safety feature, as I'm sure you'll all agree.
It seems there's still a long way to make it feasible for long haul flights but this could be great for shorter flight when speed and altitude are not an issue. Travel between small islands probably the best use case since other short routes are best covered by trains.
These types of small jumps will probably be better with battery, just because it's cheaper to fuel the planes with pure electricity.
Even in the UK getting from city by train can take half a day as you need to change, even thought the distance is not that far. So much for upgrading the railways. These short haul planes can fill the bill. Pure EV planes even more so as they are _very_ quiet, so ideal over urban areas.
@@johnburns4017 It doesn't make sense between larger cities, trains have killed a lot of flights in European countries with high speed rail. Italy and France are good examples. But electric planes make a lot of sense for more rural towns, especially when there's already airfields. Norway has a bunch of these in the north, tiny airports for tiny towns. Widerøe is working with Tecnam and SAS is working with Heart to get electric planes on the shorter haul routes. SAS as a matter of fact just announced they will soon sell tickets for the first flights in 2028. 5 years away of course, but we are getting there!
It will never be feasible for long haul flights, the energy density by volume is just too low and the equipment too heavy
@@dogjennings1171 Never say never, we can get breakthroughs in the future. But it makes sense to start with the shorter haul flights. Replace planes where trains can't replace them in a good way. But for a lot of Europe, high speed trains should be the goal. For more rural areas, smaller e-planes is a good idea.
Hydrogen is improving at a modest pace. Battery tech, EV motors, and solar seem to be improving faster and faster.
Sort of how consumer electronics spawned the battery tech needed to make EVs viable for consumers, then commercial trucks, and so on, I can see this massive swing to EVs on the ground rub off onto aircrafts. The energy density needed with possible solar panels on the aircraft make full battery electric the way to go.
It would be easier to build and maintain. Imagine airports no longer needing jet fuel services or hydrogen services. Just large battery storage and solar systems. Maybe battery swap for aircrafts will make sense, but considering the time it takes to load and unload crafts, maybe rapid charging will be all that is needed.
Hearing this guy say 2035 for their aircrafts makes me think full battery electric aircrafts have a shot at becoming the new standard.
All of that except solar panels completely covering every inch of an airport wouldnt even charge up one small aircraft. You would need a very large wind farm or nuclear power plant nearby. I do think we are on the verge of seeing some very energy dense batteries, but they will be VERY expensive... so just like cars, big upfront cost, lower downstream costs in operations and maintence. But a fully electric airport feels very very very far away. I have doubts of seeing that within my own lifetime and Im only in my mid 40s. But I still think it will beat hydrogen.
@@patreekotime4578 I have seen solar tech that was spray on and solar tech capturing a wider range of the light spectrum. This makes me believe solar tech is moving forward. It will likely show up on EVs first. We have some niche builders using it now for limited range extension, but the ever advancing computer tech and demand for better solar might get us the solar tech the is able to be used on aircraft by 2035.
I believe the next ten years will likely have more major changes to the world due to tech then the past fifty years. Just not sure governments and society will know how to deal with it all.
If you want to know about renewables and the future fully charged is the place to go, and this report is outstanding, thank you. For all the naysayers out there this shows what is possible with hydrogen fuel cell flight.
That was really cool to see some early footage of planes swapping to Hydrogen fuel, & I love that they're producing green energy on-site. Everything's in test mode currently, but I can totally see the future being even better
2:54 Bit of a weird discussion about energy density, given that (as the graph shows) aviation fuel has something like four times the _volumetric_ energy density of liquid hydrogen. Seems to me that's the factor you should be considering since the gravimetric energy density is ruined by the weight of the tanks __
Exciting times for aviation. Great presentation :)
Well narrated and very interesting video.
@fullychargedshow
One criticism I would like to point out when it comes to fuel cell-powered aircraft is that a lot of people haven't got their heads screwed on correctly about realistic efficiency versus power and very commonly assume that a 30%-40% efficient turbine powered aircraft would be less efficient than a fuel-cell powered one. In aviation, the opposite is true despite the conventional logic around hydrogen fuel cell cars and engines.
However, in reality, that common 30-40% figure includes the *propulsive* efficiency, *which is largely independent of the drive-train type but dependent on the propeller and environmental conditions.* not just the thermal efficiency. For example a GE90 or Trent XWB (I am aware this plane is a turboprop but it still requires highly engineered turbines and the argument still stands on the power requirements anyway) is actually capable of above 50% thermal efficiency, but add on the 70% propulsive efficiency and you get the cliche'd 30-40% figures.
Then add in the fact that aircraft turboprops and turbofans have power levels for those efficiencies FAR in excess of fuel cells, and the fact that many hydrogen drones exhibit fairly low efficiencies of roughly 30%, add in the extra motors needed, however lightweight they are, and one understands that there is no current realistic case optimal case for a non-combusting aircraft despite the 'futuristic' appearance of fuel cells. And then there's the durability reductions with electrochemical fuel cells.
If the fuel cell paradigm was truly advantageous, contemporary aircraft and ships would be using hydrocarbon-consuming fuel cells.
For the reasons above I would be skeptical of this company.
For spinning the propellors very efficient electric motors are used?
@@sneaky_krait7271 Downstream of the fuel cell innterms of both power and efficiency that is. I have no problem with the performance of electric motors, its just that the combustion turbine is more direct.
@@josephkolodziejski6882 I don't fully understand your point. Fuel cell has 60% efficiency and electric motor >90%. So combined about 55%, which is greater than all efficiencies you named, 30, 40 and 50% for the combustion motor.
@@sneaky_krait7271 The act of simply compressing the hydrogen into storage tanks on the aircraft destroys the efficiency of the entire hydrogen propulsion system, as it requires absolutely enormous amounts of energy.
@@PistonAvatarGuy Not a problem with compression. Electrochemical compression is capable of 85% compression efficiency and the energy can be recovered.
The use of compression is what I don't like. Energy/weight is too low to be justified, might as well be batteries.
I would imagine in the future when these might be operating they would integrate these fuel cells into the leading edge of the wing, this should cool them fast and help prevent icing at the same time
Can't believe that 2050 is talking about Sustainable Fuels.... So still burning stuff!! Yet battery density should be 400% better in 2050 than it is now. Surly there has to be a future without burning fuels.?
If its carbon neutral, who cares?
No.
@@SomeKidFromBritain If there are zero carbon solutions (and there are) then they should be the ones we use in majority. Of course as they said, SAF have a role to play for bigger planes and longer flights but the amount of carbon we have iin the atmosphere today is already a problem so we need to prioritize zero carbon solutions
@SomeKidFromBritain Carbon Neutral.... like burning Wood Pellets shipped in from Canadian Forests instead of coal..... It is sadly not the truth just because you put a name on it like Carbon Neutral... No more than it was the Truth yesterday that Boris Johnson had handed over EVERYTHING already.... When it's proved today that he was lying again...!!
@@anthonyjaccard3694zero carbon and carbon neutral are functionally the same
Imogen! Great job at FLC North on this topic. May I repeat my question? When will Airlines see value parity for domestic routes? The FCL panel suggested we were already there…
Hydrogen is only as green as its source. It only exists (on Earth) in forms bonded to other materials, from which it must be freed in order to be used. Currently the cheapest material from which to get hydrogen is natural gas. So, todays hydrogen, at best, is only as green as natural gas.
This is why, when you look behind the push for hydrogen as a fuel, you find the fossil fuel industry, since hydrogen can also be generated by processing other forms of petroleum, and even coal.
The ONLY way for hydrogen to be green is for it to come from splitting water into hydrogen and oxygen, using energy from solar, wind, hydro, or geothermal. Currently that is inefficient, and therefor not cost competitive with fossil fuel derived hydrogen.
(on edit) at 10:35 I see they are addressing this. Good on them.
The way to go! What about a look at the huge frightships? Any development der?
Congrats on 1M subscribers!
And if you have been, thanks for watching - just thought I'd put that in as Imogen didn't ;p
At 4:46 she points to the left wing and says that "on this side, that's where we've got the 600 kilowatt hydrogen fuel cell system". That is not true; the left wing has a 600 kW electric *motor* system, and nothing related to hydrogen or the fuel cell system at all. The hydrogen fuel and the entire fuel cell system are in the fuselage, in the cabin area.
It might be possible to minimise battery capacity for aviation hydrogen power systems because unlike with surface transportation, the overwhelming majority of any given flight is at a constant, very specific power level.
But it's still impossible to completely eliminate the batteries because of takeoff and landing.
The thing that hydrogen proponents are very careful to downplay is the fact that any "hydrogen-powered" vehicle is really just a BEV with the addition of the weight, complexity and failure points of the hydrogen-fueled electricity generator. It is not possible to throttle fuel cells the way ICE or Electric motors MUST be throttled in normal use, so fuel cells are really just range extenders for what is otherwise a pure BEV vehicle.
So what is the energy density of hydrogen when you factor in the weight of its container?
Really bad. 5kg of hydrogen requires a cylinder weighing 60-80kg.
Pretty low with pressure tanks like here, 1-2 kWh per kg.
For long distance flights, you will have to use liquid hydrogen in cryo tanks.
4:56 - Pure gobbledygook. Turboprop engines have gearboxes which allow them to produce as much torque as would ever be desired by an aircraft designer, electric motors offer no advantage in this area.
@@Yada-nj2ig Are you writing letters to yourself? Explain how what I said is wrong, I dare you.
@@Yada-nj2ig A) You misread my comment. I said that turbine engines have gearboxes, I didn't say that the electric motors in this aircraft have gearboxes. B) Efficiency is irrelevant in this context, as there are no electric motors that are capable of being as light and as powerful as the more powerful turbines engines that are in production. C) Electric motors are limited by the amount of heat that they can dissipate, so the amount of torque that they can produce is limited by the amount of heat that they can dissipate at a given rpm.
Good to see real development into bringing hydrogen into the air flight world. Thank you for sharing!
Is hydrogen really more energy dense than regular air plane fuel per volume? 6:35
Hydrogen about 10% of the energy of kerosine making tanks so large they’d fill the entire body of the aircraft. Depending on pressure.
Look at the chart axis labels - per kg up the vertical axis and per litre along the horizontal
They didn't say so. And no, even liquid hydrogen (cryo-cooled) has a volumetric energy density of just 2.4 kWh/litre.
1 kg of hydrogen equates to 3 kg of kerosene.
1 litre of kerosene equates to 4 litres of liquid hydrogen.
Roughly.
Without counting in the higher efficiency of an fuel cell electric drivetrain compared to gas turbines.
I suppose, 1 litre of kerosene in a gas turbine gives you as much mechanical work (propeller movement) as 2 litres of liquid hydrogen with an fuel cell electric drivetrain.
could electrici
ty be used for the initial take off and landing and then other fuels used for flying the plane (I am making the assumption that take off and landing are the most inefficient parts of a flight)
With energy density you do have to consider the weight of the tanks or battery packs and engine components obviously.
2:40 How will the density of batteries change?
Iets be honest with each other in the last 20-30 years the density didn't change upwards whatsoever.
Mr. Goodenough did us a wonderful favour with li-ion but that's where we at for the last 30 years.
No the Tesla battery change didn't increase the density of the battery, a new design allowed more lithium-ion per battery.
The fact that the battery density didn't change and it won't because you will start to upset the laws of physics - big boom - is the reason that this H solution is worked out.
They have increased massively with energy density, energy per kilogram of battery.
mate companies like catl are dong 500wh/kg cells today
@@Zarphag CATL says CATL says up to 500wh/kg.
charge/discharge cycles are unknown.
No real world implementation at the moment so at this point marketing fluff.
Amprius is also in the race for a 500wh/kg cell but hey it charges like a iPhone on a 5 watt charger.
My point is, lets see a commercial implementation instead of something in a BETA stage.
Batteries are hard to keep stable while pumping up the wh/kg without the tendency to explode.
350 bar is about 5,000 psi. There are 700 bar composite hydrogen tanks, too. That's a lot of potential energy that can change to kinetic energy very quickly.
Has episodes of fully charged said in the past that the issue isn’t energy density by weight but by volume?
Radical new efficient propeller designs could fit well with developing hydrogen/electric power trains.
This is what effective prototyping and R&D look like. Messy demo units that are big, clunky and inefficient, using off-the-shelf components that aren't a great fit for the application, loaded alongside a backup and a backup-backup... but they work anyway. ZeroAvia have built it and flown it and proven that it works. We're very used to seeing mature commercial technology, which has had decades of refinement. This is the first, ugliest version of this technology and I wish ZeroAvia the best of luck with the next version, and the next version, and the next version.
Just as a general point, you need to get Bobby Llew to talk on GB News to correct them on their hopelessly out of date "facts" on EVs...!
I imagine RL may well break out in hives at there mere thought of talking to GBN, but slather him up in E45 and I'm sure he'll survive.
1:40 *Daydreaming Impossible to Achieve !*
I wonder if liquid hydrogen could improve things.
While it is really, REALLY cold, it can be kept at atmospheric pressure. So no sturdy tanks.
And it has more energy per cubic-meter. So more oomph in the same space.
And theoretically, you could just pour it into the tank. (not sure if that is a smart idea)
While it will just evaporate and be gone after a while, that is no problem, as the plane will run exactly on these vapors. If it is not boiling into a gas fast enough to feed the fuel-cell, you could even expand it in a turbine or something. there is a lot of energy in a liquid that turns into a gas spontaneously. (see also: liquid N2 motors) While liquefying H2 takes an arse-ton of energy, you might get it back in the re-gassification. And if you're really putting your energy into making inefficient H2, you can go on and liquefy it.
Liquefied hydrogen is roughly double the density of compressed hydrogen at 10,000 pounds per square inch but requires a refrigeration plant that will keep the hydrogen below 254°C. BMW made a car using liquid hydrogen which was a nightmare because if the temperature goes above -254° C a hydrogen will be getting to flare off when you cannot park it indoors.
@@colingenge9999 right. The BMW was a disaster and a laughing stock - I remember (fun fact: I live 20 minutes from BMW head-quarters in Germany). But aircrafts don't sit around all day and get fueled once per week like cars. They get fueled up to a specific amount as per flight-plan (plus reserves) and then used right away. During use, LH2 can basically not be wasted by boil off - we want the gas to run the fuel-cell. After landing, the tank is mostly empty. Upon which they get refueled and reused. Yes. Sometimes they get parked and de-tanking would mean an extra step. Maybe boil-off is acceptable over night. Maybe a ground-based chiller can be clamped on, to re-condense boil-off. Dunno. Invent something. Yes, there are planes which sit around most of the time. Cannot catch 'em all - after all. But I guess once we get the politicians to put the correct amount of taxes onto CO2 to reflect the damage done to our Commons, companies will be getting inventive in a hurry! Or we stay on the ground with our asses. We stopped using airplanes in 2018. It was fun, while it lasted. Good bye, cheap vacations in low wage countries with loads of sunshine... But we stood by it, even if it has cost us tears and money - literally.
That's not new. Most of the interest in hydrogen in aviation assumes the use of liquified hydrogen, not compressed gas. To be practical, liquified hydrogen is kept at moderate pressure (typically at pressures up to 850 kPa or ~123 psi in industial settings), not ambient pressure... requiring pressure vessels.
5kg of hydrogen would give you, with my calculations, less than 100kWh usable energy after the fuel cells. We have cars running on the roads now with batteries in the 200kWh range. Looks to me that battery electric aviation can fill quite a big niche here.
I think it's hilarious that the "artistic" pan down from the ceiling at 3:36 shows the natural gas fired heating system in the hanger. ZeroAvia is dedicated to reducing carbon emissions, but doesn't electrically (with heat pumps) heat their own facility.
Now please do a video on Eviation as well :)
Take the hydrogen, react it with captured CO2 and make methanol. Can be stored as a liquid at atmospheric pressure and at room temperature, unlike hydrogen. No need for special high pressure tanks, just put it in the wings like regular fuel. Maybe needs different seals or something but you could run your regular turboprop engine on it. Methanol is 1/3 the energy density of kerosene so long haul flights wouldn't work, but short hops of a couple of hours would work well.
That is one option for synthetic fuel production. It is easy to use, but extremely expensive to produce.
6:38 No. Hydroge i's NOT energy dense, and certainly not so compared to aviation fuel. It has a high SPECIFIC ENERGY i.e. energy per unit mass.
Not gonna happen. You need either a massive volume of the stuff at low pressure, and that means a huge fuselage. Or you need a very cold well insulated tank, which would be very heavy for the amount of fuel you carry, or you need a thick walled high pressure tank, or you need one filled with metal hydride. All of those have an excessive weight penalty which makes them impractical.
The Russians flew an H2 powered jet around 1960 using large tanks. NASA were flying a Beech model 19 with a cryogenic tank in the mid 1970s. And in fact the first jet engine was powered on the bench by hydrogen in 1938, but it was never the plan to take it into the air like that..
Not gonna happen anytime soon, in other words.
Yeah, a cabin filled with tanks isnt commercially viable. 🤷
U anti hydrogen say the same thing as those anti ev
Technology is different. Let it resource
@@Watch-0w1 No, I am not anti-hydrogen, and I am not saying the same thing as people who are anti EV are saying at all. I'm pointing out that it is a pipe dream to imagine that this will power an airliner. It won't happen. Electric power is also not practical for long range aircraft. The only realistic solution within our grasp right now, or even in the foreseeable future. is to produce a carbon neutral liquid fuel.
Hydrogen is also not a practical fuel for cars. It simply isn't.
@@prophetsnake ammonia fuel
@@Watch-0w1 That's a different question. Besides, I thought you were all for hydrogen? Given up so easily? Please do tell me how you would fly an airplane with 300 people aboard with H2 fuel.
Go on.
I find zero emission short haul flight an interesting proposition as it could well make trains far less compelling as it removes most or all of the environmental edge they have. If you can fly intercity across a given country using fuel generated on site be it hydrogen or battery electric then you remove the need for investments such as HS2 with its massive costs and negative environmental impact.
Was that a left wheel/brake lock on landing ?
9:44 & 13:41 Yeah I thought they were setting up for some drifting haha
Making the tanks structural would make sense.
i know we could make the big round tanks structural and seat the people in the wings !!!!
It’s the physics of hydrogen that makes it an impossible fuel since compressed to 10,000 psi as in the Toyota Mirai it’s still seven times the volume of kerosene for the same energy content. The weight of those tanks is in excess of the weight of hydrogen within the tanks. To say nothing of how hydrogen attacks metal causing embrittlement. many people think it’s just a matter of the technology getting more developed, but it’s the nature of the hydrogen atom itself. That is the problem. People constantly discuss the energy density of hydrogen as being amazing with respect to weight, but weight is not the issue, it’s all about volume. Take any jet fuel powered aircraft and increase the volume of the tanks by 11 and tell me how much room you’ve got left.
This is also to say nothing about the cost of hydrogen from electrolysis being about seven times the cost of kerosene. Hydrogen is so bad That it’s extremely obvious that it will never even beat out battery powered aircraft, making me believe that it is one of the ploys of the fossil fuel industry to promote hydrogen so that we will be distracted from other meaningful ways of providing fossil fuel free transportation.
You say that it is an "impossible fuel", then you illustrate the challenges with an example from the Toyota Mirai, which is a real production car running on it. Perhaps you should consult a dictionary to learn what "impossible" means...
@@brianb-p6586 In retrospect, perhaps the only thing you could argue about is my choice of the word “impossible”. What IS true is that it’s impossible to change the physical characteristics of the element Hydrogen which is where all the problems lie and which is the subject of my posting. I assume then that you agree with everything else I wrote about Hydrogen apart from my use of the word “impossible”. IMPRACTICAL or UNECONOMIC would have been better choices.
@colingenge9999 I agree that there are significant challenges to the use of hydrogen as fuel - especially in aircraft - and that they make it largely impractical and uneconomic. There probably will be some specific applications where it is a good solution, eventually.
@@brianb-p6586 There’s been a huge market for Hydrogen as a feedstock for fertilizers and metal production but problematically, it’s touted as some miracle fuel available free in water which inspires a huge delusional following for people who simply don’t remember their high school physics but the real problem comes from gov’ts who buy into it without understanding it’s downsides. Not knowing is actually a secret way to fund Big Oil profits and distract us from workable renewables. Similar to fusion which is mostly a distraction from getting on with a transition.
The challenge for aircraft cannot be overstated when you consider its massive volume, 11 times that of kerosine which would require a volume equal to the fuselage be used to store it. Battery Electric aircraft are already working on a limited scale; that’s the future.
Could you use the pressure of hydrogen to power the motor and it reaction in the fuel ?
Should be possible. You don't feed the full 350 bars of hydrogen directly into the fuel cell anyway. Normally you use a device to lower the pressure, 'your' engine could replace that. It could increase efficiency, basically it reuses the energy that is used to compress the hydrogen in the first place.
By the way, this consumes much energy, apart from electrolysis.
I think the problem is the power to weigh racio of this type of engine. So you would need to use a lot of hydrogen in a certain period of time for any serious power, maybe more than the fuel cell needs.
... the hydrogen-electric, the fully-electric also. And, later - even purely magnetic engines, as well. Yes, to all that. Finally, in the future, (that is considered a future to this moment) the engines are purely magnetic (rotary-system based), (by that time will be called RMG's). Only collecting from the existing environment energy to run, and is also 100% pollution free, and the most-powerful flight power, ever. Presently, moving away from the fossil fuels to power the flight (irregardless the carbon issue or not) is a very good move. With an addition, that, in the future - it will be indeed revolutionized - not only the pilots, but even the passengers onboard (supervised by the PIC's) will be flying and assisting at it. Everyone onboard for a flight will be considered: a team member :).
13:09 *Would not wish to be a **-Guinea Pig-** passenger- aboard this flight along with 200 Death Wish Passengers in 2035 !*
Yellow hydrogen can be lower in terms of greenhouse gas emissions than green hydrogen, as nuclear reactors can use high temperature methods, such as high temperature electrolysis, thermal cracking or the sulphur-iodine cycle, which operate at higher efficiencies than regular electrolysis. Thermal cracking can technically be achieved via concentrating solar power, albeit at lower temperatures and lower efficiency.
Whatever happened to low pressure high density Nickel-Metal Hydride tanks?
Very early days, but great somebody is trying something
4:41 is that really a jet engine? I didn’t think they had propellers. Can any engineers out there enlighten me?
High-bypass turbofan. The front fan is an enclosed propeller providing air thrust while the turbine behind provides exhaust thrust
@@showme360 in a turbofan (which is not in this video) the gas turbine engine drives the fan... and provides some thrust directly by its exhaust flow. I'm sure that's what you meant.
Unfortunately, she used the common incorrect terminology, in which people call any gas turbine engine a "jet".
@@showme360 there is no turbofan in this video - the engines shown are a turboprop on one wing, and a electric motor set on the other wing.
Bad spin, if you want to compare the energy density of hydrogen without the weight of the tank compared to batteries should you not leave the battery out and only weigh the electrons?
I've always been very anti-hydrogen for vehicles, BEV just make more sense.
But when it comes to flying batteries really don't. If a plane is running at half capacity, you can just stick less hydrogen in it. But if its got a battery, unless you've got swappable ones, that battery is going to weigh the same with 10% charge or 100% charge.
Plane's gain efficiency the further into the flight it goes as it uses fuel and gets lighter and lighter.
A battery powered plane has to have the same efficiency at take of as it does at landing, and unless we get some fantastic new battery development, that just isn't practical.
If you stick less hydrogen in it the weight is almost the same, since most of the weight of the hydrogen fuel system is the tanks, not the hydrogen itself.
if it's 3 times as energy dense as electric in terms of weight as a complete system, it probably won't be worth it in a couple of years when battery energy density becomes twice as dense, meaning the loss of energy in making the hydrogen and marginal differences in power to weight will make it less viable unless they can get the containment of the hydrogen lighter
6:40 *Remember the Heidelberg and the R101 !*
Really interesting topic such a pity about the script, for example feeling it necessary to point out that the plane is surrounded by air, and describing the hydrogen creation process as out "pops" the hydrogen. It would be good to see the same article aimed at adults.
Their biggest obstacle is economic. Hydrogen fuel cells are expensive, hydrogen storage is expensive, and hydrogen fuel is very expensive - with "green hydrogen" being even more expensive. It's hard for any commercial airliner to justify the cost and difficulty of switching to hydrogen when the fuel costs nearly double.
Hydrogen and aircraft, what a great idea! Why has nobody ever tried that before?
It'll go down like a lead balloon
They did, it was called the Hindenburg.
@@philipperapaccioli2868 Completely different design and 90 years of technological improvements, it like saying a steam train carriage is same to a passenger car as the both have wheels and can take passengers.
It' because of politics and big oils influences over governments of the past
@@philipperapaccioli2868 I'm sure he was using sarcasm to illustrate the implication of the Hindenburg and other various hydrogen accidents. But the hydrogen wasn't the only problem with the Hindenburg, I believe the skin of the craft was flammable and once ignited by thousands of volts of built up static electricity the skin sparked between the frame and itself the gap between allowing the spark to ignite the hydrogen and kept on burning fr the plasticized covering that was doped over the cotton skin.
Hydrogen fuel cell cars don't explode , so I doubt the hydrogen fuel cell airplane would either.
Except for full-sized airliners (e.g. 737 MAX and larger), hydrogen-fuel cell technology is "a fool's errand" - With exponential improvements with battery energy density and orders of magnitude improvements in aviation motor efficiency, ALL REGIONAL FLIGHTS will quickly change to all-electric planes, whether by replacing propulsion systems, or completely NEW aircrafts, which can take advantage of a "first-principles engineering" approach (vastly more efficient and easier to fly)
Be perfect for Island hopping and internal flights in Australian outback.
The killer when burning or using a fuel cell hydrogen be it a car, lorry and esp aircraft is the cost of it... at the best of time you looking at x4 the cost vs liquid fossil fuels which means a lot higher flying costs
Yes for ground vehicles. Even worse compared to bunker fuels used by container ships. But compared to aviation fuel its probably a wash. The replacement of fuel cells is expensive and problematic though.
Last time I checked, not very long ago, their fuel cell system had a maximum output of about 100 kW, to claim that the battery system is there for redundancy in providing power to the 600 kW motor is more than a stretch. The "hydrogen electric" side is basically a battery electric system with a hydrogen range extender, not a even good one, but a very bad one, very bad in multiple ways.
The main problem with replacing fossil fuels is not lack of technically viable alternatives, it's the lack of economically viable options, because fossil fuels are extremely cheap to produce. Hydrogen is the fossil fuel industry's last big hope, as any resources intended for transition spent on hydrogen will make the period of business as usual longer, and if hydrogen reach wide use as a fuel in the foreseeable future, it will have to be produced from fossil fuels mostly, to be economically viable.
One of the huge problems with fuel cells for aviation is their ridiculous power density, the higher power density you want the lower the efficiency you'll have to accept. This is still an issue for fuel cell cars, but they have managed to cram in acceptable powerful systems with kind of acceptable efficiency, with kind of acceptable space and weigh penalty, for passenger cars! Not anywhere near good enough to replace turbo props.
Yes, you could put hydrogen tanks everywhere, but would you really want to? Just the pressure alone makes them more dangerous than jet fuel tanks, and if a tank bursts the hydrogen is very likely to explode, and make the other tanks burst and explode.
For aviation combustion engines are totally superior to fuel cells. Sure, you create NOx, but assuming "clean" hydrogen, that's the only relevant drawback, and if only used in situations pure battery electric systems aren't viable, that's not much of an issue. Zeroavia lists water vapor and contrails as relevant issues, which they are not. They also claim fuel cells are far better than combustion in that regard, which makes absolutely no sense at all, the amount of water produced is determined by the amount of hydrogen that is used, which also dictates the amount of energy extracted.
Sure, you can catch the water vapor from the fuel cell system, but if you wanted to you could du that with a piston engine powering a generator. Also, there would be about as much heat and exhaust from a fuel cell system as from a combustion engine at the same power output. Actually at very high power output for their size and weight, like almost comparable to aviation piston engines, current fuel cells would have much worse efficiency than a good piston engine, and therefor produce more heat and exhaust at same output of useful power.
"Yeah, maybe so, but fuel cells are a new technology that catch up and surpass everything else!" Nope, they're not new, the first fuel cell was invented 185 years ago, which is well before the first rechargeable battery, well before the otto engine, and the diesel engine.
So much tip-toe-ing, where boldness seems to be needed! Before u realize it, someone else will overtake you! Experimental stages require risks!
but they forget the bennefit of have a electical motor in the front wheel, for taxi to runway with lot less energy to activate extra range. perhaps a small electrical motor in each wheel, used for taxi, also have be used to rotate the wheel up to landing speed to avoid rummer burn duing landing, that will encrease the lifespan of the tires. and that will demand less rubber waste.
In the absence of suitable batteries today, hydrogen is being demonstrated here as a way to store electrical energy until technology is ready. Hydrogen per se has to be manufactured and stored, whereas electric supply is ubiquitous. This is an interim solution. CATL has already started producing cells rated at 500 Wh/kg. Doubling that figure (a fairly realistic objective) will enable aircraft designers to use batteries to power most new aircraft by the 2030s.
Systems using hydrogen for electrical storage are very useful in developing the approach needed for large construction machinery and international shipping,
Musk calculates 400Wh/kg OK for intercontinental flight.
Hydrogen will only be becessary for long flights over seas, for short flights batteries are cheaper. An aluminium air battery can be used as emergency fuel used only if the hydrogen fuel tank gets empty leaks. Aluminium air battety is not chargable but it could be swappable and since it won't be used 99.99% of the time it will be just fine.
SAS have just sold tickets for the first flight in 2028; it seems to be hybrid planes Heart Aerospace ES-30
😳9:45 rather LARGE OVER-CORRECTION, nearly wobbled...😳
I'll be that guy . FIRST.
I'm interested in seeing if hydrogen is a viable secondary propulsion system for sail boats. They drag a propeller that generates electricity to charge batteries, why not hydrogen as well?
Big heavy tanks that take up cargo and passenger space with a lower net efficency than batteries, and you cant recharge as you sail.
4:54 - If it is an electric motor - it no longer has turbine blades ;)
She should have said "propeller blades". This sort of obvious error not caught in review is typical of people writing or making videos about subjects in which they have little knowledge or familiarity.
They even admitted the cooing requirement is larger than the enormous fuel itself !!
The chief of strategy look and sound like the younger version of Jeremy Clarkson...😅. Way to go by the way!
Hydrogen is energy dense in terms of weight. But not in terms of volume.
Regarding Welding of each High Pressure Tank, have all welds been X-Rayed ? U don't want any Micro Leaks occurring...
Metal tanks are not used for hydrogen storage in vehicles, as they are too heavy.
0:07 Framerate missmatch...
Why don’t you guys say “if you have been, thank you for watching” anymore?
Great video. Sounds like a very difficult task but I can see the “easiness” of producing H2 on site at airports at least…, so reduces all those issues with transporting it, distribution… 👍👍. It’s just such a hard fuel to keep within the tanks, no leaking…
The hydrogen contained in tanks provides twice the energy density of the batteries. Then there’s the weight of the fuel cell and everything to make the system work. It would be interesting to see an energy density comparison of a complete hydrogen system compared to a complete battery system. Battery density will probably double in a few years which would mean it’s simpler, and consequently cheaper, to provide the motors with electricity direct from batteries.
While it’s good to see this innovation, the battery industry is working hard looking for ever more energy dense batteries. The hydrogen atom isn’t going to change its properties. There will be a point where batteries are a better option.
Thank you
ah never knew condensation trails cause most of the warming effect, always good to get some info out of youtube
The problem is by 2035 battery tech and the energy density of them will have come leaps and bounds by then. There’s still plenty of infrastructure issues to resolve, but I can’t see a major hydrogen market coming to fruition.
Yeah....or you COULD he completely wrong!!
Largely uninformed and pointless speculation .....with a BIAS!!
I don't know how much water is required to make H2. But if H2 powered (anything), in this case, aviation, were to become common place, I wonder how much of an impact the increasing frequency and severity of droughts would have on (reliable) production and supply.
TBC: I'm not trying to be an H2 naysayer here, merely wondering aloud.
It takes 9L of water to create 1KG of hydrogen, but no water is consumed, since you produce water when you consume the hydrogen.
Hydrogen is not exactly clean to make either. I still think they should try to upscale algae fuel. Algae absorbs CO2, has a high fat/oil content. It grows easily. So it may not reduce emissions but it should at least balance out. You can make aviation fuel from algae. It's just no one has been able to upscale it to mass produce fuel at current prices. Unless someone makes a dramatic breakthrough in battery tech that improves capacity and slashes weight. I think lots of options should be looked at.
It will only be clean in my books when the entire production and storage process is "clean."
Comparing hydrogen with its lack of green hydrogen with SAF with its lack of material is bizarre. Both solutions are vapourware.