Rolls-Royce Successfully Tests Hydrogen-Powered Jet Engine (reuters.com) 133
Britain's Rolls-Royce said it has successfully run an aircraft engine on hydrogen, a world aviation first that marks a major step towards proving the gas could be key to decarbonizing air travel. Reuters reports: The ground test, using a converted Rolls-Royce AE 2100-A regional aircraft engine, used green hydrogen created by wind and tidal power, the British company said on Monday. Rolls and its testing program partner easyJet are seeking to prove that hydrogen can safely and efficiently deliver power for civil aero engines. They said they were already planning a second set of tests, with a longer-term ambition to carry out flight tests. Hydrogen is one of a number of competing technologies that could help the aviation industry achieve its goal of becoming net zero by 2050.
Congrats (Score:2)
That is great, except water vapor causes more greenhouse effect than carbon dioxide especially if you sneak it to the upper atmosphere via a jet plane. Since nearly all water vapor is stuck in the troposphere and not in the upper layers of the atmosphere, we can handle having more of it than CO2. Reference: https://www.nasa.gov/topics/ea... [nasa.gov]
exactly - this Hydrogen good at ground level only (Score:2)
water vapor is good at the ground level and lets face it hydrogen is a better store of energy than lithium considering the environment overall.
I hope they use the learning to produce a ground level generator or some such rather than fitting it to a plane and polluting even more...
Re:exactly - this Hydrogen good at ground level on (Score:5, Informative)
hydrogen is only corrosive to certain materials (Score:2)
Yep Hydrogen does not react to everything your just being divisive and thinking about metal
dont use metal which is heavy to build things
Hydrogen is a fine energy source/sink and can be stored in carbon fiber just fine
Re: hydrogen is only corrosive to certain material (Score:2)
Re: hydrogen is only corrosive to certain material (Score:2)
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Why would you want a jet engine as a generator? Those are built to primarily generate thrust, not rotational force. Rotational force is merely a tool to generate thrust in jet engines. If you hook up a generator to a jet engine, you're going to get only a tiny portion of energy out of the fuel you'll have to spend compared to boiler coupled with a steam turbine.
We already understand the whole "hook up a boiler to a steam turbine, which is hooked to a generator that is synced to the grid". Burning hydrogen i
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shock horror you can optimise of energy generation (or Rotational force) how do you think a generator works in a power station... foolish
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Those are built to primarily generate thrust, not rotational force.
A modern aircraft engine generates >60% of its thrust from the big fan at the front. This is mechanically driven by a set of turbines at the rear of the engine core. When used in stationary power situations, you just don't put the big fan on the front and connect a generator in its place. They also add an extra low pressure turbine to the core's exhaust to recover more 'thrust' energy from it.
The brayton cycle is actually more efficient than the rankine, but obviously there are a lot of secondary factors
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Of course the person the parent is replying to is equally insane- using hydrogen, which requires metric boatloads of energy to produce, to generate energy... makes the brain bleed.
Are you an idiot? (Score:2)
"Why would you want a jet engine as a generator?"
What do you think is at the heart of all combined cycle power plants, the most efficient form of fossil fuel electricity generation? Well done, a gas turbine!
Next time get a clue before you post.
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Do you think that CCGT or OCGT operation is like that of a airliner turbofan?
Let me guess. You never saw one in real life, nor drawings of one? You just know that they share a name, "gas turbine".
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Stop digging that hole thats making you look ever more stupid and do what I suggested - go get a clue.
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I've worked in this field, as has my family for two generations before me. I actually understand the relevant systems about as far as one can without making it the subject of their masters degree.
You on the other hand really should take your own advice. Or just go off the deep end and install a F1 engine in a supertanker and wonder why it doesn't seem to move it very effectively. After all, just like turbofans and CCGTs are both gas turbines, singe cylinder high rev gasoline engines and low rpm maritime die
Re: Are you an idiot? (Score:2)
You lying twat, you have no idea. If you did you'd know that bar a few minor compressor and injector details a gas turbine and a turbo jet are virtually identical. Go educate yourself moron and next time you try to sound clever maybe stick to a subject more your intellectual level. Eg Tellytubbies.
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...which is why one can ramp up much faster than the other but can't take much load, while other can work far longer than the other and take a lot of load. It's almost like the comparison between F1 engine and maritime diesel is pretty much the same and I used it for a reason.
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Additional water-vapor mediated long-term effects of Jet exhaust (already a thing, since hydrocarbon combustion produces water as well) are zero.
Carbon mediated long-term effects of Jet exhaust are very far from zero.
I.e., something flying up in the atmosphere only causes an increase in the greenhouse effect equivalent to its action. There's no pos
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That's good, right? More room for hydrogen-powered airplanes?
Nope. Just more places like Arkansas where you can go outside into the swamp ass air at 3am and it's still 94F outside, and you're completely incapable of shedding that heat.
Yay!
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I spent about a year there, saved up money, and moved the fuck back.
I have no idea how people tolerate that climate.
I think hydrogen is the future, not electric (Score:2)
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How do you store enough hydrogen safely and compactly? It is not solved yet. They should keep researching it, but I do not think it is happening anytime soon.Batteries are better, especially when we get to solid state batteries, which will happen sooner than hydrogen.
Germany once had a plan (Score:3)
How do you store enough hydrogen safely and compactly? It is not solved yet.
Germany once had a plan for the use of hydrogen in aviation. ;-)
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How did that plan go?
As stated several times on the posts here, hydrogen is very difficult to storage, and for an aircraft is worse as the weight to keep it under pressure or cryogenic is a big problem, and hydrogen also has the bad habit of getting between molecules when leaking making metal weaker, which is probably the biggest no no for an aircraft.
Rockets can use hydrogen because they are single use (the re-usable ones do not use hydrogen and the shuttle even though the main engines were H2 the tank wa
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How did that plan go?
It created quite a mess in Lakehurst NJ in 1937.
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You store it cryogenically. Airbus have prototype tanks for this purpose now in manufacture ready for testing. I am sure that they plan to connect them to these engines. They are just doing the different bits of research in parallel.
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How do you store enough hydrogen safely and compactly? It is not solved yet. They should keep researching it, but I do not think it is happening anytime soon.Batteries are better, especially when we get to solid state batteries, which will happen sooner than hydrogen.
https://www.toyota.com/mirai/ [toyota.com]
Practical Hydrogen Problems (Score:2)
Re: Practical Hydrogen Problems (Score:2)
Supercritical LH2 would be way too annoying to handle, the tank will vent at 7 bar if it can even get there. It's just a plain old liquid.
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By the time hydrogen is here on scale, there will be a complete network of EV charging. Hydrogen is too late to the game to take over personal vehicles.
Hydrogen does, however, probably have a future for heavy transportation and in industry
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By the time hydrogen is here on scale, there will be a complete network of EV charging. Hydrogen is too late to the game to take over personal vehicles.
Hydrogen does, however, probably have a future for heavy transportation and in industry
Many large transport truck manufacturers are testing H2 power trucks on the roads right now. If they become popular they will help build out the fueling infrastructure that can then be leveraged by passenger cars as well. This is not an either/or game. No reason both technologies cannot coexist in the future.
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all nice and dandy (Score:2)
the problem will be to store LH2 in the plane
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or have to throw out the plane every couple of years because the airframe got brittle from the H2 leakages
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those two things not being exclusive from one another
World first? (Score:5, Interesting)
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I stand corrected. Misread the Wikipedia page. Actually not only was the Wright J65 the first engine to run on hydrogen they also ran on gaseous hydrogen. Link to original NASA paper: https://www1.grc.nasa.gov/wp-c... [nasa.gov]
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Being the first isn't that interesting anyway, most important is that Rolls Royce is one of the few companies that looks like it could legitimately make a hydrogen engine for production aircraft.
However, it's pretty unclear what they are claiming to be 'first' about. Those ones above were actually flying aircraft. This is just ground running an engine at low speed on hydrogen. Running a turbine on hydrogen has been done before... gas or otherwise. What Rolls Royce is claiming here is being the first to run
Not a major step (Score:2)
Hydrogen is still dumb (Score:3)
Commercial quantities of hydrogen are still made from natural gas. Using it as a fuel is simply inserting an additional step that doesn't really add value over simply burning the natural gas. Yes, there is "blue" hydrogen where the carbon is supposedly sequestered first, and "green" hydrogen made by electrolysis. But green hydrogen only makes sense in a world where there are excess quantities of electricity. As of now, excess electricity is best used on the grid to replace existing fossil grid production. Carbon sequestration for blue hydrogen is still not ready for prime time (and nobody is really sure how permanent such sequestration will be in practice).
I can see some use for hydrogen in limited grid storage applications. It's inefficient, but potentially less limited and expensive than battery storage. But for transport? I just don't see much benefit for now. Maybe one day we will have so much excess electricity from renewables that green hydrogen actually makes sense. But we are a long way from that day.
Hybrid? (Score:2)
Maybe kerosone/hydrogen, or even electric/kerosene?
I think aircraft just need full thrust when taking off or in certain maneuvers, and use way less thrust when cruising. And the energy densit of fossil fuels is still great.So maybe this could be feasible?
And aren't high bypass engines essentially big fans? I.e. most of the thrust comes from the fans spinning, and not the jet exhaust. So maybe we could spin them electrically when possible?
Why? (Score:2)
As someone who's followed development of LH2 in rocket industry, LH2 is stupidly difficult to handle. It's too cold, it leaks EVERYWHERE. It likes to combine with everything else. Not to mention the stupendous amount of insulation you need tohttps://tech.slashdot.org/story/22/11/29/017215/rolls-royce-successfully-tests-hydrogen-powered-jet-engine# avoid boiloff.
Re:More greenwashing (Score:5, Interesting)
It would make a lot more sense to use bio-fuels with only slightly modified engines, but that just raises the question of why it isn't done already.
That's simple.
While biofuels have tons of potential, they're shitty fixes at best (currently).
With LUC factored in, biofuel production can have as bad as 180 years before you've saved more carbon that you added.
That isn't to say that hydrogen is some kind of magic bullet to fixing the problem, it's just that biofuels are a far more complex problem than than you allude to.
Oh the humanity! (Score:3)
That isn't to say that hydrogen is some kind of magic bullet to fixing the problem
Yes, safe storage is a major problem as our existing history of hydrogen-based air travel shows.
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Safe storage is a problem for any combustible material.
Planes full of kerosene explode dramatically, too.
The biggest problem with Hydrogen is that it requires a regime change, a lot like electrical powered jetliners.
Planes will need to change to use it. I don't mean "you'll have to slap new motors on them", I mean you will have to design new planes.
Hydrogen has a storage difficulty, period, due to reliable cryogenics causing a huge increase in mass, but safety isn't really the primary concern.
LH2
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Safe storage is a problem for any combustible material. Planes full of kerosene explode dramatically, too.
Yes but planes do not tend to explode from a small static discharge and hydrogen is notoriously difficult to store because it is incredibly good at diffusing out of wherever it is contained and liquefying it requires maintaining very low temperatures (below ~20K at 1 atm) and/or high pressures.
Kerosene can be easily and safely stored in a simple metal tank. It doesn't need to be cooled or pressurized and it will not diffuse past a basic cap. Also, under typical conditions kerosene burns while hydrogen e
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Yes but planes do not tend to explode from a small static discharge and hydrogen is notoriously difficult to store because it is incredibly good at diffusing out of wherever it is contained and liquefying it requires maintaining very low temperatures (below ~20K at 1 atm) and/or high pressures.
Pure hydrogen will not explode from a small static discharge, either.
Both will not ignite without oxygen.
Diffusion and cryogenics are indeed the actual problems.
Both are solved problems for LH transport and use.
Where it gets complicated, is doing that on an airplane with a stricter mass budget.
Kerosene can be easily and safely stored in a simple metal tank. It doesn't need to be cooled or pressurized and it will not diffuse past a basic cap. Also, under typical conditions kerosene burns while hydrogen explodes making any leaks much more dangerous.
Under typical conditions, hydrogen is harmless.
It's only a problem if it concentrates to actually significant partial pressures.
This is why we don't have hydrogen explosions every other day.
Natural gas is als
Chance of Disaster, not total number (Score:2)
For every Hindenburg you point out, I can point out a TWA Flight 800.
Fair enough let's assume the numbers are roughly equal. Now ask yourself: how many passenger hydrogen airship flights have there been compared to passenger jet flights? It's not the actual number of incidents that make something dangerous is the chance of it happening per flight. Hydrogen airships exploding or burning happened often enough that we abandoned them as a means of transport because they were too dangerous. That has not happened with passenger jets.
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Eh. Safe storage is a problem for any combustible material. Planes full of kerosene explode dramatically, too. The biggest problem with Hydrogen is that it requires a regime change, a lot like electrical powered jetliners. Planes will need to change to use it. I don't mean "you'll have to slap new motors on them", I mean you will have to design new planes. Hydrogen has a storage difficulty, period, due to reliable cryogenics causing a huge increase in mass, but safety isn't really the primary concern.
Here's Engineering Explained's take on the Hydrogen V8 Engine Toyota built. https://www.youtube.com/watch?... [youtube.com] Yes, it would indeed be a regime change.
The best thing about the fossil fuels used for aircraft is that they decent volumetric energy density at common temperatures and pressures. With Hydrogen, we're going to need cryogenics to get to that VED. Certainly a whole new storage and transport infrastructure will be needed. And if we're talking about military jets, it will be a great attack vector,
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A great addendum. No disagreement.
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exhaust.
i am thinking that a major by product of using hydrogen is water.
water has some interesting properties.
so what are the percentages of exhaust by products
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Kerosone combustion exhaust is only a little over half water.
Water vapor "pollution" isn't a realistic issue. While it's true that it's a greenhouse gas, emitted water spends an average of 9 days in the atmosphere before ending up back on good ol' mother earth as a liquid.
CO2, on the other hand, spends between 109,500 and 365,000 days in the atmosphere.
And while it's there, the greenhouse effect it provides will also increase temperatures, increasing the a
Re: More greenwashing, biofuels produce soot? (Score:2)
This is not strictly right. Part of the exhaust when combusting hydrogen (or hydrocarbons) in air is NOx. It's not only water.
Also, condensed water vapor in the upper atmosphere is a very strong greenhouse gas. Though airline contrails may not last long, they double or triple the lifetime warming impact of air travel vs the CO2 alone. There was a measurable cooling effect during the early days of the pandemic due to reduced air travel. This is a big part of why flying is worse for the climate than ground tr
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This is not strictly right. Part of the exhaust when combusting hydrogen (or hydrocarbons) in air is NOx. It's not only water.
Fair enough- I should have said the combustion products. NOx production will happen anywhere there is flame and atmospheric air.
Also, condensed water vapor in the upper atmosphere is a very strong greenhouse gas.
Was never in contention.
Though airline contrails may not last long, they double or triple the lifetime warming impact of air travel vs the CO2 alone.
That takes about 6 asterisks to be true. But I'll grant you it's not entirely false.
The Earth's tropospheric water content reduces to basically a function of temperature, which reduces basically to a function of gaseous carbon.
You can add more water to the system, but the system will re-achieve equilibrium in a very short amount of time.
If you add more w
US Navy has run an F/A-18 Hornet on biofuel (Score:2)
It would make a lot more sense to use bio-fuels with only slightly modified engines, but that just raises the question of why it isn't done already.
It has. The US Navy has run an F/A-18 Hornet on biofuel. But that's just one test aircraft.
Re:US Navy has run an F/A-18 Hornet on biofuel (Score:5, Interesting)
The US Navy has run an F/A-18 Hornet on biofuel.
Nitpick: The Hornet used a 50/50 blend of Camelina oil [wikipedia.org] and conventional aviation fuel.
But in theory, it would have worked with 100% camelina biofuel.
But that's just one test aircraft.
The Navy's goal is to source biofuels locally from oilseed farmers so they can continue to run missions even if sea lanes are disrupted.
It could also lower costs. Fuel in Afghanistan was over $100 per gallon because of sky-high transport costs. It would have been much cheaper to buy oil from a local ex-opium farmer.
Re: More greenwashing (Score:4, Informative)
Converting the entire aviation industry to biofuel would require 10x the crop area as current bioethanol output and it's already fucking massive. Double it again for marine.
Before someone brings it up again, salt tolerant plants are irrelevant. You can't just irrigate with seawater, salt water marshes work because massive amounts of water from rivers and/or tides move through them. Those plants will only add a tiny amount of extra growing area, most has to come from arable land irrigated with fresh water.
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Converting the entire aviation industry to biofuel would require 10x the crop area as current bioethanol output and it's already fucking massive.
Well if and when we can go biofuel for aviation it will probably be bioreactor based not crop based. And the current crop numbers are inflated since we (the USA) use the wrong crops for politically expedient reasons.
Re: More greenwashing (Score:2)
Bioreactors can work, but at huge cost. Which removes the argument to just reject hydrogen out of hand.
At net zero all options are fucking expensive.
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Because we mostly use corn, and corn is the worst biofuel feedstock there is. The only reason we use it is the political clout of rural corn crowing states in the US Senate. Hemp produces *twice* the energy per acre as corn. Castor beans produce 8x, and Oil Palm produces 34x the energy per acre. Algal ponds can produce over 500x the energy per acre that corn does, and don't have to be located on arable land.
Corn sorghum, etc. are "first generation" biofuels, which are generated from food crops. Second gen
Re:More greenwashing (Score:4, Interesting)
Airbus is investing quite a bit in this. It requires a significant amount of space in the aircraft fuselage, but rather less weight which is perhaps more important. For this to work, they will use cyrogenic H2. They are also working on a propellor driven version using fuel cell I think. It's all early stage, of course, but I think they have a first generation tank ready, which means they can fit it in an existing plane, then replace one of the engines with a H2 engine and so forth.
Green hydrogen is, as you say, not that common, but this is changing very rapidly. There are GW of production capacity in various stages of planning and building including, most eye catchingly, Denmark's energy island. If floating wind turbine technology continues to develop as it is at the moment, then I think we will see more of this -- far off-shore floating wind farms generating only hydrogen for shipping back to shore.
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Large aircraft and spacecraft are actually the only vehicles it could make sense to run on hydrogen, using cryogenic H2 tanks. Blended wing body aircraft could be a good option for giving more onboard space for the fuel.
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I can see hydrogen used to power even cities etc..
It can act like a "battery" of sorts, with the excess power being turned into hydrogen and used later on to generate power when the wind/solar solutions are not delivering it
Re:More greenwashing (Score:4, Insightful)
Bio fuel comes from fields (corn and other stuff) and as such is in direct competition with the space used to grow our food. If you turned 100% of the fields cultivated for food into bio fuel, you would not have enough production to fuel the current petrol consumption (and we would all starve to death).
That's probably why it isn't done already. Because the numbers don't match.
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In India, they subsidize farmers more directly by guaranteeing a minimum sale price for their crops. It sounds better than artificially inflating demand by burning the crop in combustion engines, which is how the US is placating the farmers.
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Hydrogen is an intermediate in the production of ammonia for fertilizer, so you are still burning food.
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It would make a lot more sense to use bio-fuels with only slightly modified engines, but that just raises the question of why it isn't done already.
Biofuels don't require engine modifications, they require biofuel modifications to prevent gelling. The US military has been working on it for a while, not sure how it's going.
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If they really cared about the environment, they would lobby for a carbon tax on fossil fuels.
Forget carbon tax on fossil fuels. This is the airline industry we're talking about. *ANY* tax on jet fuel would be a start. Jet fuel is the only resource in the world subject to an international treaty which prevents countries from taxing it.
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> It would make a lot more sense to use bio-fuels
Isn't that (broadly speaking) what SAF (https://www.iata.org/en/programs/environment/sustainable-aviation-fuels/) is all about? It's making some inroads, but they can't make enough of it, and I suspect their current engines can't run 100% SAF anyway (although as you say, with some modifications they'd probably be fine). I'd also point out that SAF isn't actually all that "green" - so it's by no means a "solution", it's more of a mitigation.
With that in min
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Hydrogen is also highly inefficient, and burning it adds even more inefficiency to the mix.
You can take hydrogen and burn it and use the heat to create motion. Or you can take hydrogen and pass it through a fuel cell to create electricity which can then power a motor.
Turns out, doing the latter is far more efficient than doing the former, laws of thermodynamics ensuring that there is a limited amount of energy you can extract from heat.
Burning hydrogen really just is a stupid idea for a fuel that's already
Re: More greenwashing (Score:2)
Even if you burn it, the per kg energy density beats fossil fuels. The problem is the per m3 energy density, which is 1/3rd. Either way, you are talking about a revisualization of aircraft to something different, possibly something bigger and lighter and slower. Fancy airborn lounge and casino? Sleeper cabins above the clouds? Who knows.
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Carbon taxes will never result in the kind of environmental benefits we need to avoid catastrophic climate change. The "offsets" they offer just mean you only have to be profitable enough to pass the cost on to your customer.
Trying to figure out how to use non-carbon combustibles is a way better idea. If we don't figure it out we will have giant stacks of carbon tax credits that no one will be able to use because they are all too busy moving to the mountains to stay dry and cool.
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Hydrogen is like electricity. It's not an energy *source*; it's an energy transfer medium. I agree at present "green hydrogen" is a crock of bull. The most efficient way of generating hydrogen is from natural gas. But this is a technological question. Things can look very different twenty years from now; the way the battery situation looked very different 20 years ago.
As for the poor volumetric energy density of H2, this is offset in some applications by the excellent *mass energy density* (140 MJ/kg
Sure tax more, inflation for environazis is fun (Score:2)
Inflation is already bad enough. Add way more since everything has to be transported to get to market. How about just delivering green technology that can compete. That will get rid of ICE vehicles. Making enemies of the general public by taking food off their plate definitely won't help your cause.
Re:More greenwashing (Score:5, Informative)
Absolutely correct.
The reality is that jet engines will run on almost anything that burns.
Although they are mostly run on types of kerosene with a bunch of special additives and "tweaks" (Jet-A, Jet A1, etc), the basic combustion cycle is so very simple that they'll run on almost anything from cooking oil, through diesel to ethane, methane, methanol and other hydrocarbons.
It's pretty simple... you compress the air, add a combustible fuel (liquid or gas) and let it burn. This causes a huge increase in temperature that combines with the liberation of combustion gasses to produce a massive flow that then exits the engine to produce a reactive force in the other direction.
It's not rocket science -- although it is closely related.
So, to announce that you've been able to get one of your jet engines to run on hydrogen is a big nothing, from an engineering perspective.
Yes, hydrogen may burn slightly hotter than Jet-A1 and you will have to rejig your fuel system to accomodate the difference in viscosity and stoichiometric ratio involved (although that is surprisingly self-regulating) but the changes are pretty minimal if you just want to get the thing to run as a proof of concept.
The real problem is that hydrogen, although touted as "green" and "carbon zero", is a lousy fuel. It's particularly lousy for aviation use due to the complexities involved storing it.
Hydrogen proponents will tell you that it's a great fuel and has an energy density three times that of gasoline, diesel or Jet-A1. If you take this at face value you'll probably be wowed but when you investigate further you'll be disappointed.
Those energy density comparisions are performed on a Joules per gram basis -- ie: by weight.
Sure, 1Kg of hydrogen will deliver 120MJ of energy compared to Jet-A1's meagre 42MJ for the same weight of fuel. However, if you compare energy density by volume, hydrogen looks bad, very, very bad indeed.
One Kg of Jet-A1 takes up just over 1.1 litres of volume. To get the same amount of energy from hydrogen you'll need just 350g of the stuff but at a pressure of one atmosphere, that would be a volume of over 3,300 litres.
Of course we can compress a gas so if we used the same levels of compression as you might find in an regular industrial gas cylinder (200bar), that would bring the volume down to around 16 litres -- still around fifteen times more than jet fuel with the same amount of energy.
Not too bad?
Well let's not forget that those industrial gas cylinders are very heavy, made from thick steel that will weigh far more than the gas they are able to contain. Hydrogen's 3:1 energy density superiority by weight is utterly destroyed when you start factoring in the weight of the containment vessels.
The other option is to store the hydrogen as a liquid, using cryogenic techniques.
Liquid hydrogen has a specific gravity of just 0.07 which means that the 350g needed to match the energy of a litre of jet fuel will still require a volume of 5 litres. You're still going to need five times the volume of liquid hydrogen as you'd need of Jet-A1 -- and that's before you again factor in the overhead of the containment system. Cryo systems are neither light nor simple.
In light of this, Rolls Royce's announcement is nothing more than grandstanding and an attempt to cash in on the virtue-signalling associated with being "green".
Do not expect to see hydrogen-powered airliners in the sky any time soon, or ever.
Re: More greenwashing (Score:2)
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Taxing carbon fuels just makes travel more expensive. You aren't solving the problem of how to get more people from point A to point B efficiently.
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Taxing transportation makes travel more expensive. Taxing carbon fuels makes transportation using carbon fuels more expensive, proportionally to how much fuel they use.
See where they're going with this?
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No. You pretend as if other forms of transportation will somehow become cheaper if you tax only one, which is not the case. The fact remains that, at this point, other forms of air transportation do not exist.
If hydrogen fuel cell tech proves more-suitable to commercial jet airliners than electric, then airlines could invest in their own "green" hydrogen sources and secure their own fuel supply. Or an industry group could do the same. Just because natural gas is the current feed stock for most hydrogen
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Other forms of transportation might well become cheaper. Trains exist. More efficient use of kerosene in aircraft is also a thing. Also, taxing carbon, and the schedule of increasing taxes, seems to be making the manufacturers invest in researching alternatives. That's what this story is about after all.
Re: More greenwashing (Score:2)
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I see this claim a lot, but a bit of googling doesn't really support it. Aviation fuel is taxed in Canada, including a specific carbon tax; federally in the US plus most states add their own tax. The situation in Europe seems to be complicated, but there are taxes, and it sounds like there are going to be a lot more taxes soon.
There is an international convention that bans taxes on fuel carried on international flights by the *destination* and any jurisidictions tra
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A quick Google search shows that aviation fuels is taxed at both state and federal levels, so you are incorrect, depending on the meaning of the weasel word 'mostly'.
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I completely agree with biofuels, especially algae derived varieties. It's such an easy process, even Sandia Labs is testing it out at the Salton Sea. You need shallow water, fresh but salt will work too. Just let it fester with algae, harvest, make fuel.
https://en.wikipedia.org/wiki/... [wikipedia.org]
All these areas need is a pipeline and initial pumping to get the siphon working. It's essentially the same process that created oil in the first place (algae) but sped up.
Re: More greenwashing (Score:2)
Re: More greenwashing (Score:2)
Re:More greenwashing (Score:5, Insightful)
Effectively it is. Using public resources without paying for it is subsidizing.
Re:More greenwashing (Score:5, Insightful)
And that airport fee is paid by the airlines now? That's a new one.
Also, who gets to pay for the environment damage these planes do? Airlines?
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The airport fee is an add-on to the ticket price, just like the rebroadcast fees in TFA. The airport fee changes based on what the airport charges, and if that gets rolled up into an advertised price, it's only because the advertised price is tied to a particular flight between particular airports for a particular time -- it's not a standard, recurring subscription price.
Re: More greenwashing (Score:2)
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You won't get very far if you store hydrogen at 1 atmosphere. You might want to compress it or even liquify it. Allowing you to store much more matter(mass) in the same volume. We'd have a word for mass-divided-by-volume, it's density. Now that we established that a tank of liquid hydrogen does not make you buoyant at sea level (or higher). I'd also like to add that a full hydrogen tank weighs much more than an empty one.
If you want the specifics of why we'd jettison a tank, it is determined by the formula
Re:The Soviets had a flying jet running on hydroge (Score:4, Funny)
The Soviets had a flying jet running on hydrogen.
To rephrase an old joke:
Q. How is it that the Soviet Union has a hydrogen based jet?
A. We started with 10 of them, 9 accidents later we have the one.
Re:The Soviets had a flying jet running on hydroge (Score:4, Funny)
and you wouldn't know about them 9 because the accidents would be classified
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and you wouldn't know about them 9 because the accidents would be classified
You would know post collapse of the Soviet Union when the archives became open.
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Beware the hydrogen shortage. Stock up now!
I see the shelves in the supermarkets emptying.
We're doomed, I tell you, doomed!
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"People will still point to the Hindenberg when it comes to anything that involves hydrogen just as they do to Chernobyl when it comes to anything involving nuclear power. "
You mean because in lots of parts of the EU, half of the wild boar meat has still too much radioactive cesium to be eaten, ditto for the forest mushrooms that those boars ate?
I mean that was today on my market.
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