Home > Economics - General, Environment > The 75 per cent solution: tourism

The 75 per cent solution: tourism

December 15th, 2007

A lot of discussion of climate change is based on the implicit or explicit premise that, since we use energy in everything we do, and most energy is derived from carbon-based fuels, large reductions in CO2 emissions will require radical changes in the way we live. Some people welcome this prospect, but most do not.

Having looked at this problem in various different ways, I’m convinced that this premise is wrong, and that quite modest changes, many of which would follow more or less directly from the imposition of a suitable cost on CO2 emissions, could achieve large reductions in emissions. I’ve argued this at the macro level, based on demand elasticity estimates, and also at the micro level in terms of road transport. I thought it might be a good idea to attempt more micro estimates and, while I was visiting Cairns last week, my thoughts naturally turned to long-distance tourism.

So, this is hoped to be the first in a series where I consider the question: Could we reduce emissions in a given sector of the economy by 75 per cent in a way that wouldn’t substantially change the services delivered by that sector?

A few ground rules for the exercise before I start – there may be more as I go along.

1. I’m looking at changes over a time span of a few decades, enough that existing capital stocks are turned over. So I assume that price incentives are enough to encourage a shift to the most fuel-efficient technologies currently in use, but I don’t make any big assumptions about future innovations induced by higher prices. To take the road transport example, I can assume replacement of Hummers by Prius (BTW, what is the plural of Prius?) but I don’t invoke hydrogen fuel cells or similar exotica.

2. I’ll take it as given that the services enjoyed in the late 20th century qualify as not involving radical changes. In the case of road transport again, I might assume a return to the vehicle occupancy rates of 1990 (about 10 per cent higher than today).

3. I’m looking at reductions in emissions to deliver the existing volume of services, not taking account of growth in demand, which needs separate assessment. It’s just an exercise in arithmetic to combine the two. For example, if you predict a 60 per cent increase in demand under business as usual, then a 75 per cent reduction brings total emissions back to 40 per cent (0.25*160) of the original level, which is about what is probably needed to stabilise climate.

With these ground rules, the case of long-distance tourism turns out to be surprisingly easy, especially thanks to this piece by Justin Rowlatt who’s already looked at the question. The current airline fleet has a fuel efficiency of around 4.8 litres/passenger/100 km.[1] Replacing this fleet with the models now being introduced, the Boeing 787 and Airbus A380, will reduce this by about 50 per cent . This is going to happen anyway, and the only role for higher prices is to accelerate the scrapping of the older planes in the existing fleet.

To get a further 50 per cent reduction is even easier (this was the idea that got me started). All you need to is double the length of the average holiday and halve the frequency. I don’t have good numbers, but it’s clear that this would just take us back to the situation that prevailed a few decades ago when air travel was more expensive. Going back a bit further, travel was so expensive that young Australians typically planned a single trip to England that was to last a year (and, as far as such travel was concerned, a lifetime).

Two reductions of 50 per cent combine to give 75 per cent, so it’s all done. But that was so easy, it seemed worth trying for more. What would be involved in reducing emissions by 85 per cent, from 25 per cent of the original level to 15 per cent? That requires a further 40 per cent.

According to the International Air Transport Association, cited by Rowlatt, there’s an easy (in terms of impact on travellers, at any rate) 12 per cent to be gained from improved air traffic control. You could get another 12 per cent (at least) by packing more economy seats into planes (the A380 can take 800, at which Rowlatt estimates fuel consumption of 1.9 l/100 pkm. For the final leg, we’ll need the first actual cut, a 25 per cent reduction in the number of long-distance trips, to be replaced by local holidays with extra spending money from the saving in travel costs.

So, to sum up, let’s look at the impact of an 85 per cent reduction in emissions, achieved as outlined above. Suppose the baseline is eight one-week long-distance holidays over some given period. After the 85 per cent reduction we’d have three two-week long-distance holidays and two one-week local holidays instead. On the plane, we’d be packed in about as tight as at present, maybe a bit less so, and of course there will be lots of nice new features like free WiFi to keep us entertained.

Even with a hefty surcharge on emissions, total expenditure on airfares would fall, so there would be more money to spend on the actual holiday, not to mention the flow of revenue to governments that could be returned in tax cuts or improved services.

No doubt all this would take some adjustment. But The End Of Civilisation As We Know It, it’s not.

fn1. Because airplane emissions are injected directly into the upper atmosphere, where they do more damage, this figure can’t be compared directly with fuel efficiency measures for cars. Roughly speaking, you need to double the airplane emissions figures before doing a comparison. Of course, that doesn’t affect the calculations that follow which are all about proportional reductions.

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  1. The Doctor
    December 15th, 2007 at 15:18 | #1

    So the really big problem is changing the length & frequency of holidays involving air travel – bearing in mind that some of the suggestions(i.e. the extra seats in an A380) may cheapen that travel mode.

  2. December 15th, 2007 at 16:25 | #2

    PrQ, unfortunately jet aircraft deliver a cocktail of greenhouse gases (CO2, NOx, methane, water vapour…) directly into the stratosphere, which according to the IPCC has considerably more warming effect than the same amount of C02 emitted at ground level. Monbiot says 2.7 times as great as the carbon dioxide alone and I’ve seen this claim repeated elsewhere. Perhaps someone with more knowledge of the science could confirm this?

    Its because of this (and the near impossibility of a finding a renewable replacement for jet fuel) that many believe long-haul aviation will become increasingly untenable in the future.

    Regardless, I think your calculations are out by a factor of 2-3.

  3. jquiggin
    December 15th, 2007 at 16:52 | #3

    Carbonsink, that’s covered in the article I link to. It means that comparisons with motor vehicles are misleading, but it doesn’t affect anything in my calculations which are about proportional reductions. Still, I’ll update the post to clarify this.

  4. conrad
    December 15th, 2007 at 17:09 | #4

    I imagine it would be pretty easy for books/publishing companies. All that needs to happen is for people to take up electronic books, and no more trees, transport, etc. Someone really just needs to release something as catchy as the IPod, but for books, so that everyone starts using them. They might also like to tell all the libraries I visit (which are academic ones), that getting hard-copy versions of stuff is a waste time, since no-one actually uses them anymore. This would be even simpler, since its just a complete waste now, and you don’t even need to change people’s preferances. The same is true for newspapers. I’m sure many people would prefer to read the electronic versions, and I can’t see that diminishing. I imagine its just really just formating issues which are left for many people.

  5. Socrates
    December 15th, 2007 at 19:45 | #5

    JQ

    I agree with your objective here, and also with the suggestion that flying can be greatly improved in efficiency. It is not teh end of civilisation. However there are operational specifics that mean the gains wll not be as great as hoped IMO:
    - many routes do not have the volume to justify the most efficient jets without less frequent flights. eg most domestic Australian routes
    - turboprops will never be as efficient. They are used for short regional routes in Australia now and these will be most under threat.
    - changes to air traffic control will also depend on terminal capacity and hence often mean costly changes to airports and terminals.
    - finally, air travel has been doubling in volume every five years, so there is a fundamental problem with stopping the exponential growth. this will need a tax to curb.

    Overall I think air travel can become greener and this will mean it won’t dissappear, but the era of exponential growth and cheap weekend holidays in the Whitsundays must end IMO.

  6. chrisl
    December 15th, 2007 at 19:50 | #6

    I don’t think holidays come in neat 1 week or 2 week packages that can be easily doubled. Some family members recently took a 6 week trip to Europe.It would not have been possible to do a 12 week trip for reasons of time, finances and health.
    As for larger,more efficient jets, they would have the effect of bringing prices down and increasing passenger numbers, as happened when the jumbo jet was first introduced.
    Your theory might reduce flights by a few percent ,but nowhere near the 75% imagined.

  7. chrisl
    December 15th, 2007 at 20:12 | #7

    Rather than being surprisingly easy to change people’s flying habits I would say that it is extremely difficult as evidenced by those atteding the Bali conference.
    The 10,000 attendees could have fitted into 20 or so jumbo jets, but instead there was a log-jam of private jets(the antithesis of a jumbo)
    Or they could have tele-conferenced.

  8. Ian Gould
    December 15th, 2007 at 20:51 | #8

    Chrisl, I did a google news search for “jets Bali” and “jets Denpasar” and other than far-right sites like “American Thinker” I didn’t find a single report of this supposed log-jam.

    So it seems either the international-left-wing-journalist conspiracy suppressed the story or its something that didn’t happen but which right-wingers think SHOULD have happened.

    If you have a link for this, I’d be interested to read it.

  9. Tom Davies
    December 15th, 2007 at 21:08 | #9

    Google for ‘bali private jet parking’ — I didn’t read any of the articles, and the URLs didn’t look mainstream, but this is probably what chrisl was referring to.

    I’d be interested to know roughly what level of tax on a ticket would be needed to get people to reduce their holiday flying by 50%

  10. Ian Gould
    December 15th, 2007 at 21:45 | #10

    Okay, this is the story that seems to have started the “private jet traffic jam” meme.

    http://www.balidiscovery.com/messages/message.asp?Id=4112

    “11/3/2007) Tempo Interaktif reports that Angkasa Pura – the management of Bali’s Ngurah Rai International Airport are concerned that the large number of additional private charter flights expected in Bali during the UN Conference on Climate Change (UNFCCC) December 3-15, 2007, will exceed the carrying capacity of apron areas. To meet the added demand for aircraft storage officials are allocating “parking space” at other airports in Indonesia.

    The operational manager for Bali’s Airport, Azjar Effendi, says his 3 parking areas can only accommodate 15 planes, which means that some of the jets used by VIP delegations will only be allowed to disembark and embark their planes in Bali with parking provided at airports in Surabaya, Lombok, Jakarta and Makassar.”

    First up, let’s note that this is the December peak season for Bali tourism meaning that commercial and charter traffic is going to be at a peak anyway.

    Second let’s note that 15 private jets is hardly a massive number.

    Third, how exactly else are Kevin Rudd, Ban Ki-Moon and the other heads of state and VIPs supposed to get? Ferry? Domestic commercial flight (in a country with lax airport security and a recent history of major terrorist attacks)?

  11. chrisl
    December 15th, 2007 at 22:06 | #11

    Good find Ian:The airport manager doesn’t seem to belong to a “far-right site” as you first imagined.
    Your third point is exactly the point John Q was making in his post. More people on less flights. No excuses. BTW I think Kevin Rudd was the only head of state who atteded.
    Then there is this from the Guardian:
    The Guardian, Saturday December 15 2007
    The 15,000 politicians, activists, MPs, journalists, and civil servants from 180 countries who travelled to Bali for the talks emitted between 60,000 and 100,000 tonnes of carbon dioxide, according to estimates. This is not far short of what a country like Malawi or Chad emits in a year, the UN said yesterday. The greatest emissions resulted from flights to and from Indonesia

  12. Hermit
    December 15th, 2007 at 22:15 | #12

    The fact that a couple of B&Bs near home have closed suggests that people are taking fewer holidays. I wonder if they will take longer holidays if there are worries about job security. Air fares will increase when transport is included in the EU Emissions Trading Scheme though I haven’t heard of any additional penalty for the altitude factor. Could be why Virgin also run train services in the UK, though Heathrow airport is set to expand. Note that some are claiming that primary petroleum liquids are in a 3-4% annual production decline. Bio– jet fuel has been found wanting so if coal based fuel is needed that will attract a roughly double carbon penalty.

    I suspect people who stick to travel plans are going out less mid year or not updating home electronics.

  13. Ian Gould
    December 15th, 2007 at 22:19 | #13

    ChrisL, does the Guardian mention that Indonesia planted 79 million trees to offset the emissions caused by the conference?

  14. chrisl
    December 15th, 2007 at 22:52 | #14

    Ian: Why yes,but you already knew that…..

    Host nation Indonesia said it had planted 79 million trees to offset the conference’s emissions, but tree planting is not considered suitable by most analysts. “We have to know where the trees will be planted and make sure that they grow and will not be cut down until they make enough carbon stock,” said Amanda Katili, special assistant to the Indonesian environment minister, Rachmat Witoelar.

    David Adam, the Guardian’s sole correspondent in Bali, had his carbon footprint offset in a scheme by Climate Care, which invests in renewable energy in developing countries.

  15. mugwump
    December 16th, 2007 at 06:49 | #15

    I don’t have good numbers, but it’s clear that this would just take us back to the situation that prevailed a few decades ago when air travel was more expensive.

    Indeed. And I bet an across-the board “back to the sixties” policy will get you your 75% reduction in all industries (actually, it is closer to 50% since relying on the efficiency of A380s and 787s for all airline travel is misleading: there are a huge number of routes for which they are not an economical aircraft choice).

    Maybe going back to the sixties is appealing to baby-boomers, but the rest of us would rather not undo several decades of living standard improvements (and that goes 10-fold for developing nations).

  16. Socrates
    December 16th, 2007 at 08:35 | #16

    A correction to my post #5 – I should have said that airline traffic was doubling approximately every ten years, not five years. Bad maths day. Otherwise I believe my points were accurate.

    As an aside, I think it is big destinations like Bali that will be most able to benefit from economies of scale and stay in business. Small regional airports are the ones that will suffer most with any sort of realistic carbon tax on flying.

    Offset schemes are one solution, but I wonder if there is enough tree planting in the whole world to offset all the emissions we want to offest. Plus IMO there is a need for accreditaion and auditing of offset schemes. The variation in cost and claimed volume of offset is alarming.

  17. December 16th, 2007 at 09:13 | #17

    the only long term solution to an over-full planet is fewer people. inviting riders to stand closer together and breathe less is not a solution, just a temporary palliative.

    this is apparently ‘too hard’ for politicians, academics, and property developers. one can sympathize with people who can’t speak for fear of blighting a career, but retired curmudgeons are free to speak, fortunately for you.

    unfortunately, until respectable professionals begin to realize there are career prospects in reporting reality, we’re not going to get very far. so quit counting angels on pinheads, the situation is serious.

  18. Alexander McLeay
    December 16th, 2007 at 09:28 | #18

    John Quiggin, I’m going to go out on a limb and say that “Prii” is the plural of “Prius”.

    Conrad, I think there’s still a lot of technical advances of needed before we can switch from paper books to ebooks.

    Ebooks are a lot less comfortable than paper books. Even a hardcover book isn’t as uncomfortable to hold as a plastic box. Screen resolutions need to get a lot higher. Even very high 200 dpi resolutions are nasty compared to your average desktop laser printer (600 dpi) or books and newspapers. Also, backlit screens have nothing to recommend themselves, compared with pages of paper. We’re simply not designed to stare at backlights all day.

    Convenience. There are only two things required for me to read a book: It needs to be in English (or have lots of pictures), and I need to have it with me. Ebooks will make it easier for me to have any random book with me at any time, but introduce a lot of other problems. I probably need to be inside because the contrast isn’t high enough to compete with the sun; I need to have batteries enough to last; the ebook needs to be in the same format as my reader supports.

    For studying purposes, ebooks also lack direct manipulation. Probably there exist ebook readers with stili and highlighter tools and everything, but with a pen/cil on paper there’s never any worry about calibration or accidentally marking it with your finger or having to work out where the blasted button that switches between pen and highlighter mode are.

  19. Katz
    December 16th, 2007 at 09:37 | #19

    Maybe going back to the sixties is appealing to baby-boomers, but the rest of us would rather not undo several decades of living standard improvements (and that goes 10-fold for developing nations).

    But Mugwump, the preferences of baby-boomers are immaterial to the issue being discussed.

    The question is: can the efficiencies calculated by JQ be achieved without returning to those patterns of the 1960s?

    And to anticipate one answer you may give: yes, most folks would like the freedom to travel when and as they like. But who will be able to afford it under the scenarios canvassed by JQ?

    And do you perceive any other likely scenarios that are radically different from that one so helpfully provided by JQ?

  20. mugwump
    December 16th, 2007 at 11:08 | #20

    Offset schemes are one solution, but I wonder if there is enough tree planting in the whole world to offset all the emissions we want to offest.

    I did a quick calculation on this a while back. Even under the most optimistic of assumptions, by my reckoning planting the entire arable land surface of the Earth with trees will sequester 100 years of human CO2 emissions. So realistically, offsets will maybe buy us one or two years at most. [remember, once the forests are mature they no longer continue to sequester because any uptake of CO2 by growing trees is offset by the dead and rotting ones]

    And do you perceive any other likely scenarios that are radically different from that one so helpfully provided by JQ?

    Sure. Don’t pick on air travel. It contributes very little to the overall CO2 picture; it is an integral part of modern western lifestyle; it is very popular; and it is uniquely dependent on very high-density fuel, which means – at least within the visible technical horizon – it is dependent on hydrocarbon fuels and hence on cheap CO2 emissions.

    OTOH, terrestrial travel has far greater prospects of conversion to alternative fuel sources. As does terrestrial industry and other big CO2 generating activities such as home heating.

    If we go nuclear we can “clean up” a lot of industries that are currently reliant on “unclean” energy sources. It makes no sense to force the airline industry to lower emissions; pick the low-hanging fruit first.

  21. Ian Gould
    December 16th, 2007 at 11:38 | #21

    “the only long term solution to an over-full planet is fewer people.”

    Oddly, few advocates of this position seem prepared to volunteer to be part of the solution themselves.

  22. jquiggin
    December 16th, 2007 at 11:54 | #22

    Hi, mugwump and welcome back. Not surprisingly, I’m in a pretty happy mood, with Howard gone in large measure due to his recalcitrance on Kyoto.

    On #20, I do indeed intend to cover those topics. I picked air travel for tourism first precisely because it seemed likely to be the most intractable. But as the post shows, very large reductions in emissions can be made with only marginal inconvenience arising as a result.

    On fuel efficiency, I agree that the 50 per cent reduction somewhat overstates the effect of replacing the current fleet with the best aircraft now on the market. But against that, there are some further improvements that can be expected on the newish designs (A380, B787, A350 and various short-haul planes). In addition, there are a bunch of minor tweaks that can be expected to yield additional savings. For example, in a lot of cases, the reduced damage from flying below the tropopause will more than offset marginal losses in fuel efficiency. Also, with quieter designs, we could allow more night flights, which also reduces damage.

  23. mugwump
    December 16th, 2007 at 12:55 | #23

    But as the post shows, very large reductions in emissions can be made with only marginal inconvenience arising as a result.

    The post doesn’t show anything of the sort. You get the extra 50% reduction in emissions from the trivial assumption that people reduce their vacation travel by 50%. There’s no analysis of the cost of such a reduction, except the hand-waving “it’s no worse than the 60s”.

    A lot of things could change such that they’re no worse than the 60s, but unless you are a baby-boomer hankering for the halcyon days of Vietnam protest, bad drugs, and “free” love, you are unlikely to regard a return to the 60s as a “marginal inconvenience”.

    For some people the inconvenience of a 50% reduction in vacation travel may well only be “marginal”; for others it would mean completely forgoing their usual vacation plans.

    The convoluted special pleading of the Bali delegates in justifying their preferred mode of transport shows just how addicted we have become to cheap, convenient, air travel.

  24. Ernestine Gross
    December 16th, 2007 at 15:46 | #24

    To JQ re “According to the International Air Transport Association, cited by Rowlatt, there’s an easy (in terms of impact on travellers, at any rate) 12 per cent to be gained from improved air traffic control. You could get another 12 per cent (at least) by packing more economy seats into planes (the A380 can take 800, at which Rowlatt estimates fuel consumption of 1.9 l/100 pkm. ….”

    The qualification “in terms of impact on travellers� is the crucial statement.

    The International Air Transport Association’s data amounts to focusing on one negative externality only, namely CO2 emissions. It is known from the theory of incomplete markets (even though I can’t quote the crucial reference from the top of my head right now) that adding one market without completing the markets can leave everybody worse off. A sharp theoretical result of this kind is, IMHO, primarily useful for pointing to major problems.

    There are many other incomplete market problems associated with air transport. There are other air pollution problems and there is aircraft noise (unwanted sound; negative externality).

    It is known that in the case of Sydney, ‘improved air traffic control’ would mean concentrated flight paths over residential areas stretching about 35 km to the north of Sydney Airport with max noise events in the range of 60 to 82 dBA, given the current fleet, from 6:00 am to 11:00pm more or less non-stop for at least 86% of the time, measured in years. The horrific effects of such noise pollution on ‘consumers’ are recorded in the 1995 Senate Select Committee Report on Aircraft Noise in Sydney, Falling on Deaf Ears?. At the time the aviation industry had argued for ‘improved air traffic control’, not for environmental reasons but for profitability of air lines.

    So, I would accept the ‘improved air traffic control’ argument only if air traffic noise, air pollution and the risk of a crash in urban areas is priced at the same time and included in the air fares. I am pretty confident in saying that the effect of pricing aircraft noise alone would reduce the value of Sydney Airport considerably. (Pilot study by Gross and Sim, 1998).

  25. December 16th, 2007 at 19:07 | #25

    Looking at this another way Monbiot claims:

    that to achieve stabilisation the weight of carbon emissions per person should be no greater than 0.33 tonnes

    However according to this carbon emissions calculator a single return flight from Sydney to London would emit 3.7 tonnes of CO2 and a “Total Warming Effect” of 11 tonnes of C02 equivalent.

    If these numbers are accurate, or even close to accurate, long haul flights are simply unsustainable.

  26. chrisl
    December 16th, 2007 at 19:36 | #26

    What are you saying Carbonsink?
    Does this mean no more Bali conferences?

  27. Katz
    December 16th, 2007 at 20:42 | #27

    Sure. Don’t pick on air travel. It contributes very little to the overall CO2 picture; it is an integral part of modern western lifestyle; it is very popular; and it is uniquely dependent on very high-density fuel, which means – at least within the visible technical horizon – it is dependent on hydrocarbon fuels and hence on cheap CO2 emissions.

    But Mugwump. If you accept that air travel is among the least intractable issues causing the rise in GGs, then you should be happy about discussing means by which the effects of air travel may be mitigated.

    Only then, once we have established parameters, should we momve on to more difficult, perhaps more intractable, issues.

  28. December 16th, 2007 at 21:44 | #28

    chrisl: Yes no more Bali conferences. No more economists flying to Cairns for conferences about global warming’s effect on coral reefs (tell that one to your grandkids PrQ!) No more conferences period.

    Pretty much everyone is in denial about air travel. Both denial that its completely unsustainable, and denial that the only solution is to not fly.

    Of course the other issue that mugwump alluded to is that air travel is uniquely reliant on hydrocarbon fuels, and unlike stationary electricity generation and ground transportation, there is no alternative to the kerosense-fuelled jet engine on the horizon … and if you hadn’t noticed, hydrocarbon fuels are getting a bit pricey lately.

    Katz: air travel may be “among the least intractable issues” in terms of its total contribution to global carbon emissions, but in terms of growth rates of emissions and solutions/alternatives it is one of the most intractable issues.

  29. Katz
    December 17th, 2007 at 05:54 | #29

    But Carbonsink.

    Who is in deeper denial, JQ or Mugwump?

    JQ says to Mugwump: “Travel like its 1968. Then we can all continue to do it.”

    Mugwump says to JQ: “I intend to travel like it’s the 21st century, when jet travel has never been cheaper. And even if it becomes prohibitively expensive, let the market allocate expensive resources.”

  30. mugwump
    December 17th, 2007 at 06:42 | #30

    But Mugwump. If you accept that air travel is among the least intractable issues causing the rise in GGs

    No Katz, I am saying the opposite. There are no alternative fuel sources for planes. You can’t whack a dirty great lead-acid battery in a 747 and call it a hybrid; it won’t fly (literally).

    If the airline industry was a huge contributor to the CO2 problem (and if the CO2 problem is really as bad as people have been led to believe, which I strongly doubt, but that’s another argument), then we’d have to think seriously about curtailing air travel. But it’s not a big contributor, so I would suggest that because of the lack of alternatives, commercial airlines should not be required to reduce CO2 as much as other industries where there are alternatives.

  31. December 17th, 2007 at 06:54 | #31

    One further point I’d make about air travel is that the extra forcing effects of the high-altitude travel can be reduced a lot by flying a little lower.

    This actually means more CO2, but less overall warming.

    As to the claim that there aren’t any substitutes for petroleum for jets, the modest total fuel requirements of airliners could realistically be met by biofuels.

  32. December 17th, 2007 at 07:08 | #32

    Katz, I think mugwump’s view that we’ll keep flying like its the 21st century until something makes it prohibitively expensive is far more likely to eventuate. The chances of any government anywhere imposing flight quotas or draconian carbon taxes on air travel are basically nil (for the 5-10 years at least).

    I think the oil markets will eventually do the trick, but so far there’s very little evidence of that. Lets face it, oil is up 30% this year, but there’s been no discernable increase in ticket prices, and I can still fly between any east coast capital for less than $100.

  33. mugwump
    December 17th, 2007 at 07:09 | #33

    As to the claim that there aren’t any substitutes for petroleum for jets, the modest total fuel requirements of airliners could realistically be met by biofuels.

    True. What I mean is there are no non-CO2 emitting alternatives.

  34. December 17th, 2007 at 07:14 | #34

    As to the claim that there aren’t any substitutes for petroleum for jets, the modest total fuel requirements of airliners could realistically be met by biofuels.

    Perhaps, but how do we arrange markets so that biofuel production is exclusively dedicated to jet fuel? The only way I can see that happening is if (fossil) petroluem becomes prohibitively expensive, and ground transportation is electrified.

    Also, the rapid growth of air travel means the growth of biofuel production would need to be similarly rapid.

  35. December 17th, 2007 at 08:01 | #35

    Ah well, as long as wealthy socialists can still afford to fly it’s all good.

  36. Katz
    December 17th, 2007 at 08:28 | #36

    Is there a website that sells airline tickets exclusively to wealthy socialists Yobbo?

    If so, what is its URL?

    Even though I am not a socialist, I can easily pass for one, especially online.

    I should like to avail myself of this no doubt superior service.

  37. salient green
    December 17th, 2007 at 08:50 | #37

    Pure hydrogen will fuel a jet engine. There is still work to be done on storage but the high pressures needed to liquify H2 are a source of energy recovered in-flight and then you burn it.

    Ceramic fuel cells are another option for fueling airplanes, running on H2 and more efficient than jet engines, they would power electric motor driven fans.

  38. Avi
    December 17th, 2007 at 09:06 | #38

    Very interesting post John. This shows impressive reductions in air travel emissions at minimal inconvenience. However, I’d like to see similar reductions in the construction of those planes to be really convinced.

  39. December 17th, 2007 at 09:08 | #39

    #37 Insert hydrogen debunking here:

    Unfortunately, when hydrogen burns, it creates water. A hydrogen plane will produce 2.6 times as much water vapour as a plane running on kerosene. This, they admit, would be a major problem if hydrogen planes flew as high as ordinary craft. But if the aircraft flew below 10,000 metres (33,000ft), where contrails are less likely to form, the impact would be negligible. What they have forgotten is that because hydrogen requires a far bigger fuel tank than kerosene, the structure (or “airframe”) of the plane would need to be much larger. This means it would be subject to more drag. The Royal Commission points out that “the combination of larger drag and lower weight would require flight at higher altitudes” than planes fuelled by kerosene. In fact, hydrogen planes, if they are ever used, are most likely to be deployed as supersonic jets in the stratosphere. If so, their impact on the climate would be around 13 times that of a normal aircraft running on kerosene.

    And that, I’m afraid, is that. As the Intergovernmental Panel on Climate Change discovered, “There would not appear to be any practical alternatives to kerosene-based fuels for commercial jet aircraft for the next several decades.” There is, in other words, no technofix.

    George W. Bush is a big fan of both the “hydrogen economy” and (corn) ethanol. That should give people a clue about the viability of both.

  40. salient green
    December 17th, 2007 at 13:18 | #40

    Carbonsink, I think both George Monbiot and the IPCC are being very pessimistic in stating that practical alternatives to kerosine are several decades away. This link http://www.h2hh.de/downloads/Westenberger.pdf shows how H2 can be stored and used in jet aircraft. I think that, even putting environmental reasons aside, kerosine shortage could make it more expensive than H2 from renewable sources within two decades.
    George Bush hasn’t got the brains to become a fan of the hydrogen economy all by himself.

  41. December 17th, 2007 at 15:03 | #41

    Bah! That’s not pessimism. Spend a few hours at a peak oil doomer site. Now that’s pessimism.

  42. MH
    December 17th, 2007 at 15:17 | #42

    JQ et al

    A turboprop (Say a DASH 8) as used by Qantas Link all over queensland is very efficient indeed. A Dash will only burn about 16 litres for 30 passengers between Townsville and Cairns and 10 litres per passenger for the same route if the acft is full (50 pax). I know of no motor vehicle that will transport anybody between Townsville and Cairs for the total consumption of only 10 litres. That is the benefit of economies of scale when mechanisation is applied to transport problems. Many contributors mistake large fuel loads for miserable economy. A turbo prop is actually even more efficient than a pure jet. The same as a piston engined aircraft is 90% more efficient again, except you cannot build a piston engine that produces the equivalent of 150,000 such as powers a Airbus A380. Janes Aircraft publishes the specific fuel consumption figures for aircraft engines of all types if any body cares to check the data. The fuel improvements in engine (specific fuel burn) has been minimal over the past decade or two, it is improving the drag and altitude capability which is giving the much improved economies. The higher you can go the faster you can go for the same fuel.

  43. MH
    December 17th, 2007 at 15:26 | #43

    Addendum – Dash8 fuel burn demonstrates the argument JQ made at outset the moor people you carry the less fuel burn per person, 1 or 50 same fuel burn. (150,000 is horsepower. True airspeed increases with altitude due to temp and press changes.

    The only variable that may change any possible gains is the weather, the worse the weather the more fuel you waste going around it or waiting for it to get better. Climtae change scenarios suggest any improvements as per the discussion will vanish due to fuel v safety. ATC benefits are at the limit of our technology unless we want completely automated sequencing ala automatic trains, aeroplanes already travel in straight lines, it is the congestion at the arrival or departure point that costs. It also costs for pax offloaded to carry fuel for the congestion.

  44. Lobes
    December 17th, 2007 at 17:06 | #44

    As long as the suggestion to double the length of holidays and halve their frequency is still on the table there is always the option of using a hydrogen airship. This would be slower than a jet aircraft but still much quicker than the equivalent journey by boat. The H2 lifting gas could also be used as a fuel source and the extra length of the holiday means that the longer travel time would be less of a penalty.

  45. December 17th, 2007 at 17:35 | #45

    I know of no motor vehicle that will transport anybody between Townsville and Cairs for the total consumption of only 10 litres

    My diesel VW Jetta does better than 5L/100km on the open road and comfortably seats 4 adults and their luggage. Townsville to Cairns is ~350km which would require 17.5L of fuel @ 5L/100km. That’s just 4.375L per passenger.

    That said, I agree entirely with you about turbo props — I think we’ll be seeing a lot more of them in the future.

    And they’re not that slow. According to this a Dash 8 will cruise at 600kph which is about two-thirds the speed of a jet airliner. So the Australia-Europe trip might take an extra 12 hours or so. Not such a huge burden to bear to save the planet methinks.

  46. December 18th, 2007 at 10:07 | #46

    WRT hydrogen planes, there seems to be an assumption that the conventional tube-with-wings-carrying-turbofans design will be retained.

    Given the extra burden that hydrogen will place on aircraft, it’s possible that alternative configurations like the blended wing body will become attractive.

    Furthermore, instead of turbofans, something like propfans might be appealing. A propfan gets you about 20% better specific fuel consumption than current designs, but at a noise penalty (they’ll be as noisy as the latest aircraft, rather than being much quieter as a next-gen turbofan would be).

  47. December 18th, 2007 at 10:13 | #47

    A final point: one wonders whether piston engined airliners will make a return, based on those kind of figures.

    Lockheed Super Constellations used to cruise at about 570 km/h.

  48. Lobes
    December 18th, 2007 at 12:13 | #48

    Blended wing bodies are much more efficient but suffer from not providing enough window seats and the fact that when the aircraft banks those in the outer seats move dozens of meters above or below the centerline which has an effect on the G-loading IIRC. They are also more difficult to evacuate in an emergency and are apparently a pig to fly with a need for complicated avionics.

    Still, none of those are deal breakers the real impediment seems to be no-one wants to be the first constructor to build one of the freaks as they are scared nobody will buy them. But the B2 bomber stands as a testament to their effectiveness.

    The Soviets also did some research into ground effect craft that fly at low altitude over the water.
    http://en.wikipedia.org/wiki/Wing-In-Ground_effect_vehicle

  49. December 18th, 2007 at 12:34 | #49

    A final point: one wonders whether piston engined airliners will make a return, based on those kind of figures.

    I believe turboprops are much more efficient than piston-engined planes. Propfans are slightly faster again, with cruising speeds up to 700kph. (most jets cruise at ~900kph)

    Considering how much the A380 cost to develop, I doubt we’ll see any blended wing designs in the skies during my lifetime (and I’m hoping to live at least another 40 years).

  50. December 18th, 2007 at 13:22 | #50

    Carbonsink: surprisingly not.

    See, for instance, here.

    The complicating factor is the extra weight of piston designs, but you’d wonder what modern engine designers could do if assigned the task of a really efficient large aircraft piston engine.

  51. December 18th, 2007 at 17:30 | #51

    you’d wonder what modern engine designers could do if assigned the task of a really efficient large aircraft piston engine.

    Yeah … it seems all propeller planes hit the wall at about 700kph, which is only ~25% slower than a jet. That doesn’t seem too big a price to pay.

    I mean, we gave up supersonic airliners recently with very little pain, surely we can give up jets as well?

  52. Ian Gould
    December 20th, 2007 at 20:26 | #52

    I know next to nothing about aircraft engines but I was inspired by the discussion here to do a little research via wikipedia (usual caveats apply).

    Back in the 50′s and 60′s both the US and the USSR operated turboprop passenger aircraft on intercontinental routes.

    How did the fuel efficiency of these aircraft compare with modern jetliners?

    The Tupolev 114 seems to have been the last of the big turboprop peassnger aircraft.

    It carried 200 passsengers, had a range of 6,000 kilometres and a cruise speed of 770 kmh.

    Comparable figures for the new Boeing Dreamliner (specifically the 787-8).

    210-250 passsengers, range of 14-15,000 kilometres, cruise speed of 902 kmh.

    Of course, a modern large turboprop would use fly-by-wire and composite materials meaning it’s purpose would be better than the Tu-114′s.

    The one bit of data I can’t find is the critical one: how does the fuel consumption compare?

  53. Stephen L
    January 1st, 2008 at 22:10 | #53

    Getting away from the speculation about aircraft technologies, the idea of halving the number of holidays and doubling their length is certainly oversimplification.

    My parents travel annually to the UK to see my nephews and nieces. By the time they’ve been there five weeks they have had enough, its the seeing them at each stage of their growth they’re keen on. Nevertheless, there are other economies you don’t mention – we can’t get London to Cairns done by rail, but maybe Brisbane to Cairns could be.

    So if we can achieve 20% from things you don’t mention maybe this could allow us to have, in your example, two two week long distance holidays, one two week local holiday and two one week long distance holiday. That seems to me a lot more realistic.

    The major thing is probably to get a cultural change, where taking longer but rarer holidays is expected, rather than something that tends to annoy your boss.

  54. wilful
    January 2nd, 2008 at 08:57 | #54

    If there was a continental bullet train, from Adelaide or Melbourne to Brisbane or Cairns, I wouldn’t fly very often. It would solve a lot of Australia’s airline emissions. Of course, QANTAS would lobby fiercely for it to not happen.

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