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Can redesigning aeroplanes save the planet?

edwest2

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If only... as the climate disaster/crisis takes form, or something.

 

Orionblamblam

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Yes, redesigning airplanes will save the planet. What you need to do:
1: Delete the wings.
2: Delete the filthy, filthy hydrocarbon burning turbofans.
3: Build the structure not from eeeeeevil carbon, but from daisy-fresh steel, aluminum and titanium
4: Make sure to include a circular mild steel pusher plate massing a thousand tons or more with appropriate pneumatic shock absorbers.
5: As we all know, the only thing more eeeevil than carbon is weapons-grade fissionables, so load up your new airplane with a few thousand pulse units.
6: Short trips are inefficient and thus bad for the environment. See you on Titan, chumps!
 

pathology_doc

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My call: The BBC is full of it.

I don't want to get more political than that on these boards, but the complete lack of independent thought being demonstrated in that article is of grave concern.
 

Justo Miranda

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Agent provocateur:(

Otzi the iceman had smoker's lung

SCIENTISTS have revealed that a 5,300-year-old mummy found frozen in a glacier suffered from a bad case of smoker's lung, his lungs were blackened, probably from breathing in campfire smoke.
 
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Zoo Tycoon

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Here in Europe, there’s a massively pro hydrogen lobby. Whenever the Hydrogen high priest or disciples publish articles they’re routinely highly bias, showing no desire to waste words describing the difficult technical issues. So in order to provide some balance, here’s a really difficult issue for hydrogen, atmospheric leakage, indeed its Hydrogen’s dirty little secret ;-

It goes like this;- Hydrogen is the smallest molecule so will diffuse through metal and even glass. A high pressure hydrogen tank will bleed to empty in a little over a week if unused. Hence about 6-12% (depending on storage time) is inherently leaked into the atmosphere.

Now here’s the dirty part;- H2 vented into the atmosphere has a global warming potential (GWP) of 5.8;- that’s one ton of H2 in the atmosphere has the same impact as 5.8 tons of CO2. So assuming 12% inherent leakage into atmosphere will come from every ton of hydrogen produced, even if it’s end use turns it 100% into water, just using it will have the same effect of releasing 0.7tons of CO2 (for reference;- one ton of kerosene will produce 2.7 tons of CO2). In order to give some idea of an existing example, the Space Shuttle used only 56% of the hydrogen supplied in total to the program.

By simple examination any claims of hydrogen being zero emissions is deception.

(Repeated from hydrogen transport thread as seems appropriate)
 

UpForce

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If only... as the climate disaster/crisis takes form, or something.

That headline is very click-bait-y and I'm pretty sure whoever at BBC wrote it knows as much. They got me though and unsurprisingly the content was underwhelming, just running through some near future R&D projects, it wasn't even very comprehensive. On the positive side, somewhere among there they managed to put the environmental challenges of aviation to scale.

As always, it's unlikely there are no silver bullets but nonetheless it is equally clear that responsibility about sustainability can't be outsourced to individual "consumers". Also, what was lacking in that article, I think, was that a rather minuscule part of world population is responsible for the most of the flying and the associated detrimental effects. As always, agency, power and wealth weigh heavily on whether social incentives to find actual solutions (beyond their ultimate links to immutable natural laws) exist.
 

Archibald

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Here in Europe, there’s a massively pro hydrogen lobby. Whenever the Hydrogen high priest or disciples publish articles they’re routinely highly bias, showing no desire to waste words describing the difficult technical issues. So in order to provide some balance, here’s a really difficult issue for hydrogen, atmospheric leakage, indeed its Hydrogen’s dirty little secret ;-

It goes like this;- Hydrogen is the smallest molecule so will diffuse through metal and even glass. A high pressure hydrogen tank will bleed to empty in a little over a week if unused. Hence about 6-12% (depending on storage time) is inherently leaked into the atmosphere.

Now here’s the dirty part;- H2 vented into the atmosphere has a global warming potential (GWP) of 5.8;- that’s one ton of H2 in the atmosphere has the same impact as 5.8 tons of CO2. So assuming 12% inherent leakage into atmosphere will come from every ton of hydrogen produced, even if it’s end use turns it 100% into water, just using it will have the same effect of releasing 0.7tons of CO2 (for reference;- one ton of kerosene will produce 2.7 tons of CO2). In order to give some idea of an existing example, the Space Shuttle used only 56% of the hydrogen supplied in total to the program.

By simple examination any claims of hydrogen being zero emissions is deception.

(Repeated from hydrogen transport thread as seems appropriate)

Thanks very much for that important point. Never knew that - makes LH2 as fuel looks even sillier.

I vote instead for REL smart idea of ammonia cracking into hydrogen during flight - with ammonia usual caveats.

That headline is very click-bait-y

That's an understatement. And quite shameful for the BBC - put it at the level of standard Internet clickbait B.S...

the Space Shuttle used only 56% of the hydrogen supplied in total to the program.

I knew boiloff was a major PITA for the space program, but not to this point. Wow, no surprise LH2 orbital propellant depots never happened - even Musk ran away from them.
 
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Zoo Tycoon

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LH2 has even worse leakage than pressurised H2, due to boil off and what’s called loading loss. Loading loss is the venting required during LH2 tank filling and is very high if you want to transfer a large quantity quickly. The Space Shuttle would transfer 135 tons of LH2 to put 103tons in the tank in three hours thus venting 32 tons, or 170 ton transfer in 2hours venting 67tons. Now consider that a big European or American hub airport would be using maybe 10K tons per day and expecting tank filling in under an hour, so how much would be lost?

By comparison Ammonia is water soluble so invariably gets washed out of the atmosphere. Also Ammonia is part of a natural cycle almost as old as the planet’s atmosphere ie the nitrogen cycle, so is in a state of continuous decay and renewal. We currently directly soil inject about 150 million tons every year for agriculture which is tiny fraction of the amount occurring in the natural cycle.

However despite Ammonia having zero global warming potential, a natural atmospheric decay cycle, rapid transfer, easy and leak free storage, the hydrogen religion in Europe lacks interested in it’s development as an energy carrier. Shame really given all the hype about being so eco focused and motivated.
 
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Archibald

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LH2 has even worse leakage than pressurised H2, due to boil off and what’s called loading loss. Loading loss is the venting required during LH2 tank filling and is very high if you want to transfer a large quantity quickly. The Space Shuttle would transfer 135 tons of LH2 to put 103tons in the tank in three hours thus venting 32 tons, or 170 ton transfer in 2hours venting 67tons. Now consider that a big European or American hub airport would be using maybe 10K tons per day and expecting tank filling in under an hour, so how much would be lost?

By comparison Ammonia is water soluble so invariably gets washed out of the atmosphere. Also Ammonia is part of a natural cycle almost as old as the planet atmosphere ie the nitrogen cycle, so is in a state of continuous decay and renewal. We currently directly soil inject about 150 million tons every year for agriculture which is tiny fraction of the amount occurring in the natural cycle.

However despite Ammonia having zero global warming potential, a natural atmospheric decay cycle, rapid transfer, easy and leak free storage, the hydrogen religion in Europe lacks interested in it’s development as an energy carrier. Shame really given all the hype about being so eco focused and motivated.

Spot on. The main argument used against ammonia relates to its current production - admittedly, moving the CO2 pollution elsewhere.
Except that... nuclear power and solar thermal / solar power could be used to produce "clean" ammonia.
 

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