Well, yes, but it doesn’t matter

Airships for city hops could cut flying’s CO2 emissions by 90%

By all means try it out and see what happens.

But aviation is only 2% of emissions anyway. It’s simply not important to reduce them further.

That is, even if we accept – I know, I know – the initial claims it’s still true that reducing aviation emissions is a rounding error. Which does rather produce some wonder at the insistences made about it.

55 thoughts on “Well, yes, but it doesn’t matter”

  1. If it cuts Co2 emissions by 90% it presumably cuts fuel costs by 90%. That does have to be offset against greater crew costs as they will take longer to get anywhere, but on the plus side they don’t need a runway to operate from; one could fly one straight to a factory roof and load there, then offload on the distribution centre roof.

    The greenwashing is a way to attract interest, but it does highlight a potential benefit, albeit indirectly. I, in case you hadn’t noticed, am quite pro airship.

  2. Airships are like hovercraft – ideal for dealing with areas with no infrastructure and difficult terrain. However, such places have few or no people, so not much need for transport in or out. For anywhere else we have far more efficient means of transport so hovercraft and airships will always have marginal uses.

    Also, the specific company talked about has a production capacity of maybe 12 airships a year. That’s not going to take a large bite out of the existing air travel market.

  3. I was reading only yesterday a claim that the current number of airships is only in the double digits. Must be a reason for that.

  4. What’s the benefit of a 5 hour flight from Liverpool to Belfast over an 8 hour overnight ferry? You travel while you sleep, so make use of dead time.

    The problem with 5 hour flight for that journey is that then becomes an overnight stop seeing your client. With check in etc, the Easyjet flight is 3 hours. 3 hours means getting up, getting to the airport early, into Belfast for about 10. See the client, leave about 5, home for around 9pm. Long day, but still possible. 5 hours means getting to the client for 12pm, and to get home for 9pm, you’re leaving at 3.

    This is the sort of thing no-one grasps. Extra speed (like paying for planes) is often really valuable. You save on a night in a hotel, that’s £100 alone. Tax me £30 if you like to plant some trees, it’s still going to be worth it.

  5. It would be interesting to see the sums, but as BiC says, it has never made sense before. Unless your idea of a sensible transport system is, say, HS2.

  6. Zeppelins work fine. If your destination happens to be downwind… If there isn’t too much wind.. If…

    About as practical as a flying car.

  7. They also use a rare resource – helium. Hydrogen is really too dangerous especially for passenger transport. Helium is really hard to keep in a vessel like an airship – being a very small atom it finds its way through most materials.

  8. As already mentioned, flight times are the problem.
    They say liverpool to belfast in 5 hours 20, eastJet say 50 minutes.

    They claim this is mitigated by time it takes to get to and through the aiport, but:
    A) Either they will be operating as a private business jet basis, so going from smaller airfields just the same as the other business jets in terms of getting their and security, or
    B) They are operating as a commercial scheduled airline, which means they have to fly from airports with the right fire fighting coverage and I can see no reason why they would treat security any different.

    They might be lower carbon emissions but at the massive expense of speed and weather tolerance. Increased flight times mean more labour costs, food and entertainment requirements etc so I doubt the ticket costs will even be cheaper.

  9. @ BiW

    “Assuming the wind isn’t too strong. See Bruce Dickinson’s flying arse breaking free of its moorings for a demonstration of what happens otherwise”

    My flying instructor used to say, “If it looks right, it flies right”.

    I wouldn’t get on an Airlander for that reason along.

  10. Also economies of scale. How many passengers and how much freight can an airship carry. What is it’s turnaround time ? Many airlines do not simply do A-B-A flights but A-B-C-A. One assumes that the engines are electric so will they need recharging ?

    Helium – there was great excitement a while back about a new source of natural helium caused by radioactive decay. It was somewhere like Zambia, so the Chinese probably already have grabbed it.

  11. Tanzania. And all helium is from radioactive decay. Further, the process of making liquefied natural gas means that there’s much more helium available for use than there used to be.

  12. Damn, what with this, and the mysterious wobbly skyscraper in China the other day, I picked a great time to rewatch ‘Fringe’ from the very beginning!

  13. all helium is from radioactive decay.

    Not from the Sun it ain’t. when oh when will Elon Musk get that pipeline built to channel all that helium going to waste inside the sun ?

  14. Airships don’t ‘hop’, they wallow about.

    Airships, like sailing ships, are heavily weather dependent and at the mercy of the winds.

    There is a reason why we moved away from sailing ships and why airships (or battery electric vehicles) never caught on.

    ‘Green’ means reverting to former inefficient technology in the name of misanthropy.

  15. Problem is some of airship advantages are not unique but in combination they are (eg loiter/on station time, speed relative to ships, platform size, options to integrate sensors into structure-especially large ones that normally have to be in ships, satellite-style persistence)

    Problem is they are outweighed by their disadvantages (vulnerability, slow transit speeds, weather effects, support infrastructure, maneuverability)

    The pros can be delivered by blimps at lower cost

  16. Re why are the Green nutters going after something that is only 2% of emissions. Firstly it is very visible, and therefore symbolic. Secondly if everyone claimed their emissions were too small to bother about nobody would do anything. So there is some kind of internal logic, if you accept the premise which no-one here does, with the possible exception of Tim.

    The next couple of decades is going to be interesting. Because all the easy reductions have been done. For instance all the windmills producing electricity. Well there are fewer carbon emissions from generation, at the expense of having two parallel generating systems. One for when the wind blows, and one for when it doesn’t. But the cost system for electricity is so opaque it’s not clear just how much consumers have been impacted by this. Sure at the margins a few pensioners have probably died earlier than otherwise from the cold, but who cares. Not the Greenies.

    But now they’re coming for things which will impact the general public, and they’re starting to notice. All the low traffic neighbourhoods etc. There was an article in the Daily Mail yesterday about why converting all household heating from gas to something else was not feasible in any sensible timescale. What’s going to happen there. Up until now you’ve been able to virtual signal at virtually no cost to yourself. That’s about to change.

    Mind you the Great British public have applauded as they’ve been put under house arrest for the last year, so who knows they might welcome freezing to death in their own homes.

  17. The idea will die a death when St Emma of Thompson realises it would take her 3 days to pop over to LA for a coffee. If the weather was right.

  18. Helium is fairly cheap (well, affordable) because it is a by-product of oil and gas wells. Any He in soil or air will escape to outer space. As we move away from fossil fuels, we’ll have to pay squillions for He.

    It is a chemical fact that you can’t beat kerosene, which has the highest possible energy density. (H + O2 may be efficient for space rockets, but for atmospheric engines the O2 is free, abundant and doesn’t have to be carried on board.)

  19. ‘Airships in Pullman’s books, or in Steampunk, are great in fiction’

    Must admit I find the idea of a nuclear powered airship charming. And no CO2 emissions either.

    I’d love to hear the shrieks of the Greens if someone actually tried it.

  20. They’re going after air travel for the same reason they’re going after meat: The people need to suffer for their sins against the goddess.

    Once you accept that the whole climate change/ eco bollocks deal is a religion then it all becomes very clear.

    We’ve built incredibly efficient, relatively inexpensive systems to allow everyone to heat and light their houses and places of work, travel anywhere, either locally or internationally at their own convenience, eat like kings of old and generally have long, comfortable and fulfilling lives.

    Of course they need to tear it all down.

  21. As the token pro-airship poster so far, you’ll note I talked about freight rather than passenger transport; competing with ships on speed rather than fixed wing ac and, in the scenario I posited, reducing handling costs. For passengers, I’d envisage something akin to an air cruise rather than a point to point transport solution.

  22. @JuliaM
    One of my favourite shows. Watch out for the Duchess of Sussex at the start of season 2.

  23. @MrWomby: Yes! I’m up to ep10, season 3, and she seems to have only had about two outings.

    She wasn’t bad, I thought more was going to be done with her character, particularly with her reliance on the Bible..

  24. As our host points out, Helium is available as a side product of LNG (and Oil) production. If we go zero carbon, how much LNG/Oil production will there be, in which case what price Helium?

    Helicopters used to be used into city centres, until one fell off the Pan Am roof into a NY street. How long till said city-centre passenger airship does the same? Cityscapes are bloggers for turbulence.

    “H + O2 may be efficient for space rockets,”
    Not really, no. It amazes me that back in the 1950s anyone thought this was a good idea. But they did, and once developed, it stuck. It’s actually quite mad.

    LH/LOX may have the highest specific impulse, in theory, but LH has such low density you end up with an enormous tank to hold it: the structural weight of the monster largely negating the specific impulse benefits.
    Worse, the reaction is so energetic that the resultant gas is so hot that a large amount of the reagants are disassociated, i.e. only burn outside the rocket, and are therefore useless. This is solved by using a very fuel-rich mixture (not stoichometric) which makes the LH tank even bigger and heavier: by 2-3x for the shuttle IIRC.
    Oh, and while the SI may be high, the thrust isn’t, so you cannot use LH/LOX for a 1st stage, ‘cos it’d never lift off the ground. Ariane, Shuttle and the Japanese thing all use fireworks bolted on the side as 1st stage thrust for take off (the main engine being more of a 1st/2nd stage sustainer, Atlas-style). Old Werner knew what he was doing with RP1/LOX in Staurn V 1st stage.

    Finally, LH is far tougher cryogenically than LOX, so the tank insulation, piping, everything, is even harder, heavier and more expensive (and error prone).

    In the commercial world, LH/LOX is not just Barking, it’s Upminster.
    SpaceX know this, and having copied Werner for Merlin, now use Methane/LOX for Raptor, which is almost as good as LH/LOX wrt SI and much much easier in structure and the launch site bits. Cheaper too.

    But Zeppelins do have a place for cinematic rapid unscheduled disassemblies 🙂
    Just so long as I’m a long way away please.

  25. @JuliaM
    There was a story that Anna Torv wanted to leave after the first season, so Olivia was to have died following the crash in S2E1; the Megster would then take over as the female lead. Luckily for us Anna changed her mind. Interesting to speculate on how things may have developed in real life had MM stayed on.

  26. Why on earth would I fly for “city hops”? I’d get in the car – or even a train. Flight is for inter-country travel not intra-country travel, certainly not for inter-city travel. By the time I’ve got the bus to the train station to catch the train to the airport to get through check-in and get on the ‘plane, I’d already have driven there. Hierarchy of methods and all that.

  27. The problems with airships are many, but the biggie is that it’s slow. So slow that it’s only really an option for very short flights. But short flights over land have to compete with high-speed rail (and mostly can’t – France’s “ban” on short-haul was completely pointless, the handful of remaining flights on those routes were overwhelmingly transfer passengers, and transfer passengers are still permitted). Airships are going to be slower than the train.

    Short-haul over water (like Liverpool-Belfast or Barcelona-Parma) is slightly more reasonable, but faces the problem that battery-powered planes can cover those same routes, are already higher capacity than the airship, use infrastructure that already exists, are much less weather-dependent and are faster.

    Airship infrastructure is a lot cheaper than runways for aeroplanes, so for places like Bumfuck, Montana that get two flights a day and are the only airport for a couple hundred miles around – yes, why not just have an airship once or twice a day instead, have a mooring mast instead of a concrete runway, and save a ton of money. And maybe some CO2 emissions into the bargain.

    But it’s a tiny fraction of air emissions and those are a tiny fraction of overall CO2.

    The biggest emitters where there are technical solutions that “just” need implementing are electricity (mostly grid-level storage, and long-distance transmission, we can then build solar in places where the sun shines and export it), road transportation (battery-electric vehicles) and non-industrial buildings heating and cooking (switch to electricity) and deforestation (we could just, uh, stop)

    The big ones where there aren’t technical solutions are industrial furnaces (high temperatures are very expensive from electrical heating), concrete manufacturing (cement emits CO2), some other chemical processes that emit CO2 (e.g. various metal ores are carbonates and emit CO2 when the metal is extracted), agriculture (especially livestock – unless you think that “Impossible Burgers” are a just-needs-scaling-up solution).

    Those two paragraphs each add up to about half of global emissions. Maybe 60-40. The only way to net zero is to have large-scale carbon sinks removing carbon. That means a lot of reforestation. And once you’ve admitted that net zero doesn’t mean zero emissions, or even close, then the odd 2% here or there isn’t a huge deal.

  28. The only way to net zero is to have large-scale carbon sinks removing carbon. That means a lot of reforestation.

    And you (as in, net zero ecomentalists) can’t do that. Planting lots of forests to “soak up carbon” might prompt the masses to realise that CO2 is plant food.

  29. @JuliaM- “I picked a great time to rewatch ‘Fringe’” – unintentional Airplane ref? I picked a great time to quit sniffing glue.

  30. . . . freight rather than passenger transport; competing with ships on speed rather than fixed wing ac and, in the scenario I posited, reducing handling costs.

    Thing is, fixed wing aircraft (like the beautiful Jumbos I still get to see lifting off from East Mids) are already commercially brilliant at transporting virtually all items that need to go fast. Nearly everything else can go by ship because it doesn’t need to go fast.

    The direct factory to distribution centre scenario is only cost saving in theory. The airship is far too vulnerable to winds / weather for those cost savings to be greater than costs due to unreliability of service. Container ships can transit and dock in all but the most diabolical conditions, and if they need to loiter they don’t end up in Uzbekistan.

    For passengers, I’d envisage something akin to an air cruise rather than a point to point transport solution.

    I know someone who set up a company running a sight-seeing Zeppelin around California. If it didn’t work there (it didn’t) it ain’t viable.

    My heart likes the idea of giant airships in the sky but my head overrules.

  31. “Oh, and while the SI may be high, the thrust isn’t, so you cannot use LH/LOX for a 1st stage, ‘cos it’d never lift off the ground”

    Delta IV can get into space with a pure H2/O2 system, but it’s also a ridiculous rocket. Only three out of 29 of the “Medium” launches have had a low enough payload not to need strap-on solid rocket boosters – though there have also been 12 Delta IV Heavy launches. Which requires a rocket as big as the Falcon Heavy to get the same payload as a single Falcon 9.

    In fact, Delta IV is the real proof that hydrolox is a bad idea, which is why ULA has switched to methalox for Vulcan (as has Blue Origin from New Shepard to New Glenn).

    The only under-development hydrolox rockets are Ariane 6 (ESA), and H-3 (JAXA), both of which were specified over a decade ago, and both rely on strap-on solid boosters to get any useful payload to orbit – a design that precludes reusability, which is why no-one wants to go that way since SpaceX proved that reusing rockets was both technically possible and saved an enormous amount of money.

    Most rockets in development are either RP-1/O2 (a bunch of Russian rockets, Long March 9, Rocket Lab Neutron), or methalox (SpaceX Starship, Blue Origin New Glenn, ULA Vulcan, Roscosmos Amur).

    I’ve excluded the many small-rocket companies that have never launched anything and are using a wide variety of technologies because most of them will never get off the ground.

  32. Why on earth would I fly for “city hops”?

    Because “you” are rich and have access to helicopters.

  33. Yes, hecalopters would work, 15 second walk to the roof of my penthouse, 15 second walk off the roof of the destination.

  34. It must be a chore to keep those grass airstrips in New guinea free of weeds. Weather at the equator is quite predictable so airships could be a solution in isolated mountainous terrain. i.e. a ver small market.
    They do use dirigible balloons to harvest samples from the jungle canopy in Brazil and places like that, but that’s a niche too.
    I think I’ll keep my yacht.

  35. @MrWimby: Well, if Harry had ended up with Anna Torv instead, he’d probably have been a lot happier…

    @HallowedBe: you might think that, I couldn’t possibly comment…

  36. Reforestation as a carbon sink? I’m not sure if that even works.
    Lets actually look at what’s going on. plants use chlorophyll & sunlight to turn CO2 + water into plant matter. mostly cellulose. Any area of ground under sunlight will have about the same area of leaves metabolising CO2 + H2O into cellulose. The clue being, when looked at from above, they’re all green. So you must end up with the same mass of cellulose. Trees express it as wood. All cellulose will eventually be broken down by bacteria & be returned to the carbon cycle either as CO2 directly or via methane. The only difference being woo hangs around longer. However, as anyone knows who’s dug under a forest, trees don’t produce soil. Grasses etc produce soil. Soil contains a high proportion of carbon. Can be mostly carbon. And soil hangs around for ever. Undisturbed grassland produces a few millimetres a year. You’ll have noticed that the lawn you planted 30 years ago was lower than the path you laid at the same time. It’s now considerably higher despite your mower grazing it off every couple of weeks. Agricultural land produces soil much quicker because it’s constantly being turned with the plough. Can be yards deep. Be interesting to know from Jim the mass of the annual hay crop can be taken of an acre of grass. I’d guess it’s suspiciously similar to the mass of wood growth you’d get if you planted trees. Although some of that will have fallen as leaves in the autumn. So I’d suggest that agriculture sequesters carbon quicker & more lastingly than forested land. So why the fuck are we reforesting?

  37. If you want to talk about airships, a heavier than air airship is probably the way to go. That has an aerofoil shape but derives a proportion of its structural rigidity by containing a gas. Using helium would provide added lift. (Hot helium moreso?) Problem being that aerodynamic lift equals drag. So you have to put energy into the system to make it fly. Modern composites to keep the frame weight down. Use of aerogels. Skinning it with a photovoltaic material to generate electricity for motors. It might work. If you didn’t want to fly at night.

  38. Just a thought. That’s the sort of thing could work very well on Mars. CO2 atmosphere denser for the same pressure. Larger usable temperature gradient.

  39. Sorry about the Mars airships, nice idea but won’t work.
    The buoyancy is equal to the weight of the atmosphere displaced, less that of whatever is doing the displacing. So at 1% atmospheric pressure, everything is 100 times less than on Earth.
    OK, marginal gain ‘cos CO2 molecular weight is slightly greater than N2/O2, but nowhere near the 100:1.
    So you need something 100 times bigger for the same lift, with no extra weight.

    Conversely, on Venus, airships are the thing!

  40. @Tim the Coder
    They’ve got a helicopter to work on Mars. Aerofoils definitely work. Parachutes are used in landing. And it’s the aerofoil part of the lift that’s significant. The buoyancy would make takeoffs & landings a lot easier. And with buoyancy, large works in your favour. Volume increases by the cube whilst surface area by the square.
    I didn’t just invent this. It’s been talked about since at least the 80s

  41. The point of Venusian airships would be to permanently float high where the crushing pressure isn’t a problem. To completely avoid the sulphuric acid clouds would add further height, so any human involvement would require heavy (for an airship) pressurisation facilities. It soon becomes impractical even without considering how you transport, deliver, construct and maintain such devices.

    A robot balloon mission seems immediately possible and may be the best way to investigate the unknowns of the atmosphere, including if life is present.

  42. Pressure isn’t relevant, because an airship/balloon has the same pressure inside as outside, apart from any marginal over-pressure for inflation of the blimp variety.
    What matters is the buoyancy of the volume, less the weight of the envelope and payload.
    Earth atmosphere at sea level, is 1g/litre (roughly), or 1kg/cubic metre.
    That’s the maximum possible, and filling the envelope with H2 or He is very close to it. (Molecular weights 28.8-2 for H2 i.e. 27g, or 29-4 for He, i.e. 25g lift per 22.4 liters).
    On Mars, or Venus the Molecular Weight difference is 44-2 or 44-4 for H2 and He repectively.
    But with pressure at 1% of Earth (Mars) this means a lift of 0.4g per litre. Ouch.
    On Venus surface, at 70 atm, this means a lift of nearly 3kg/litre!

    Agreed, the problem of the heat and the sulphuric acid mean that such exploits are likely to be robot probes drifting in the upper Venusian atmosphere. But still, it’s a nice idea.

    Re, Mars, yes you can fly, but you need a low wing loading and high airspeed to generate enough lift (downwards momentum of the air). The helicopter had huge and very fast blades. Marvellous to watch. Air much much thinner than even U2 territory. Which also means parachutres are good for slowing from supersonic speeds, but no good for landing. Requires either a powered descent for the last bit, or a bouncy castle for the little-uns.

    Venusian airships….gotta be space pirates!

  43. Before anyone points it out, I bungled the sums, and I also neglected temperature, which makes Mars 2x better, and Venus 3x worse. But whether arithmetically challenged or not, at 1% atmosphere, there’s just not enough gas to displace to get any significant buoyancy.

    Mars, roughly 0.04g/litre lift (wrt Earth: MW 2x, Absolute Temp @ 150K 2x, Pressure /100)
    Venus, roughly 37g/litre lift (wrt Earth: MW 2x, Absolute Temp @ 900K /3, Pressure 70x)


  44. The big ones where there aren’t technical solutions are industrial furnaces (high temperatures are very expensive from electrical heating), concrete manufacturing (cement emits CO2), some other chemical processes that emit CO2 (e.g. various metal ores are carbonates and emit CO2 when the metal is extracted), agriculture (especially livestock – unless you think that “Impossible Burgers” are a just-needs-scaling-up solution).

    Re agriculture, I’ve asked (here and elsewhere) why vegetation eaten by (say) cows produces more GHG than vegetation simply left to die and rot back in a natural cycle. All the greenies I’ve put this too immediately wander off to talking about deforestation in the Amazon (not really an issue for UK agriculture, if it’s even an issue at all).

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