Math! How much CO2 is released by Aeroplane?

Another math time! :D

After car, another transport vehicle which under the sportlight of GW issue is aeroplane. Thus, this time I set out to search for how much CO2 is emitted by plane flight.

According to Energy Information Association of US, the emission coefficient of greenhouse gases for certain type of fuel is listed. Among the fuels which associated with aviation are:

  1. Aviation Gasoline: 18.355 pounds CO2 per gallon or 2.199 kg CO2 per liter.
  2. Jet Fuel: 21.095 pounds CO2 per gallon or 2.527 kg CO2 per liter.
  3. Kerosene: 21.537 pounds CO2 per gallon or 2.580 kg CO2 per liter.

Most of the jet or commercial plane is using kerosene. Thus, the CO2 emission coefficient value of 2.58 kg/L will be used for all the calculation below.

Let’s assume that a person is about to travel for a distance of 1000 km. With this distance, how much CO2 will be emitted if he is:

1. Taking a private jet, Bombardier Learjet 45 Super-Light Business Jet.

  • Normal cruise speed = 846 km/h
  • Fuel consumption at average cruise = 579 L/h
  • Passenger capacity = 9 (max)
  • Fuel consumption per km = 579 ÷ 846 = 0.684 L/km

Thus, CO2 emission rate = 0.684 x 2.580 = 1.766 kg/km

2. Taking Airbus series, like

    a) Airbus A321

  • Cruising speed = 853 km/h
  • Fuel consumption = 3000 L/h
  • Passenger capacity = 189 (max)
  • Fuel consumption per km = 3000 ÷ 853 = 3.517 L/km

Thus, CO2 emission rate = 3.517 x 2.580 = 9.074 kg/km

    b) Airbus A320

  • Cruising speed = 853 km/h
  • Fuel consumption = 3025 L/h
  • Passenger capacity = 150 (max)
  • Fuel consumption per km = 3025 ÷ 853 = 3.546 L/km

Thus, CO2 emission rate = 3.546 x 2.580 = 9.149 kg/km

3. Taking Boeing series

    a) 737-400

  • Cruising speed = 809 km/h
  • Fuel consumption = 2377 kg/h or 2935 L/h (kerosene density = 0.81 kg/L)
  • Passenger capacity = 168 (max)
  • Fuel consumption per km = 2935 ÷ 809 = 3.628 L/km

Thus, CO2 emission rate = 3.628 x 2.580 = 9.360 kg/km

    b) 737-600

  • Cruising speed = 853 km/h
  • Fuel consumption = 1932 kg/h or 2385 L/h (kerosene density = 0.81 kg/L)
  • Passenger capacity = 145 (max)
  • Fuel consumption per km = 2385 ÷ 853 = 2.796 L/km

Thus, CO2 emission rate = 2.796 x 2.580 = 7.214 kg/km

    c) 747-400

  • Cruising speed = 910 km/h
  • Passenger capacity = 409 (max)
  • Fuel consumption per km = 11.875  L/km (5 gallon per mile)

Thus, CO2 emission rate = 11.875 x 2.580 = 30.638 kg/km

4. Taking SAS Airline. SAS Blue Airline offer the emission calculator which can be used to find out the CO2 emission for 3 types of flight: RJ100, RJ85 and MD90.

    a) RJ100

  • Passenger capacity = 99 (max)
  • Distance travelled = 1846 km (assuming from Helsinki to London Heathrow)
  • Fuel burned = 7442 L
  • CO2 emission = 18754 kg

Thus, CO2 emission rate = 18754 ÷ 1846 = 10. 159 kg/km

    b) RJ185

  • Passenger capacity = 84 (max)
  • Distance travelled = 1846 km (assuming from Helsinki to London Heathrow)
  • Fuel burned = 6904 L
  • CO2 emission = 17398 kg

Thus, CO2 emission rate = 17398 ÷ 1846 = 9.425 kg/km

    c) MD90

  • Passenger capacity = 166 (max)
  • Distance travelled = 1846 km (assuming from Helsinki to London Heathrow)
  • Fuel burned = 8461 L
  • CO2 emission = 21269 kg

Thus, CO2 emission rate = 21269 ÷ 1846 = 11.522 kg/km

All these emission rate will be normalized to the CO2 per person who travel 1000 km, on various type of aeroplanes. And assuming the average cabin factor of 70% (i.e. 70% out of full passenger capacity), the comparison is made in the table below:

So, a range of 68.7 to 159.7 kg of CO2 is emitted for the same travelling distance, 1000km, depending on type of plane a person takes.

On another note, remember my ex-small compact car, Kelisa? On average, Kelisa emits 121g CO2 per km. For 1000km, 121kg of CO2 will emitted by this car. However, if it is more than 1 person in the same car, the CO2 emission per person will be reduced and smaller value than the plane.

30 Comments

  1. zewt said,

    May 8, 2007 at 2:34 pm

    what about the A380? i like this post… always love planes. but not when they are polutting the air… sigh…

  2. mich said,

    May 9, 2007 at 1:45 am

    I tried to search for the fuel consumption or CO2 emission for A380 but nothing much found.
    Hmmm, another point is that I am not sure I would call CO2 as pollutant. After all, CO2 is very much needed for plant and is crucial of keeping the earth warm. As a matter of fact, what you are breathing out now is actually CO2 rite? :P What is causing this global warming threat is due to the imbalance of CO2 in the natural cycle. CO2 is leased out way too much compared to the way it was kept…

  3. Paul said,

    May 20, 2007 at 3:10 pm

    Nice work and presentation, but your assumptions are slightly flawed. Firstly, jet aircraft actually use jet fuel, which is basically kerosene – but in any case, the amount of CO2 produced when burning any oil based fuel is close to 3 times the weight of the fuel burnt. You can check this out by doing the chemical equations and working out the products of combustion. However, this only affects answers in about the third significant figure, so this doesn’t matter much.

    3000 litres per hour is a good figure for a typical fuel flow for an A320/321 in the cruise, but you can’t really simply multiply that by the length of the flight to get the total fuel burnt – or if it happens to be right, this is by luck rather than design. Fuel flow at take-off is nearer 8000 l/h, and the total fuel used in an economical descent (which may take 25-30 minutes) might be 250 kg – just over 300 litres. It might average out right – but an overall trip fuel burn would be a more representative basis for a calculation.

    What would be really interesting – and which you could show very easily – is how many fewer kg of CO2 are emitted per person if an aircraft is operated at a consistently high load factor (say 85%, which is typical of the low-cost airlines) compared to a lower load factor (say 70%, typical of flag carriers and legacy airlines). Locos make the case that by flying full, new airliners, they are being more environmentally friendly than other airlines – and certainly aircraft where a large section of the cabin is set aside for relatively few high-yield business class pax make more for the airline but are obviously significantly more damaging to the environment.

  4. mich said,

    May 21, 2007 at 12:34 am

    Hi Paul:
    Thanks for your feedback. Allow me to break your questions into different segments:
    1) Fuel burnt and CO2 emission. For all the calculation above, I used kerosene as my jet engine fuel, thus 2.58kg CO2 per 1 L kerosene emission factor is used. How do I get 2.58kg CO2/L? Got this from Energy Information Association (EIA). And this number is actually tallied with your claim: the density of kerosene is 0.81 kg/L, thus 1 L kerosene weighted 0.81kg and emitted 2.58kg CO2. That’s pretty consistent with your number up there: the amount of CO2 produced when burning any oil based fuel is close to 3 times the weight of the fuel burnt. I used the number given in EIA, kinda lucky because I bumped into it, and also kinda lazy for me to check out the chemical formulas and sort out the number by myself by chemical equation. But thanks to your kind reminder, now I am pretty sure the EIA number is correct and true with the verification here :) [to be continued...]

  5. mich said,

    May 21, 2007 at 5:05 am

    2) I must admit that when I made the crude assumption made for calculating the fuel consumption and subsequently the CO2 emission, I placed a great faith in the numbers/values I obtained from the sites I cited above. I supposed the 8000L/h for take off number work only for A321 or it would work for a range of different engines or weight or even aircraft? Moreover, now as I think about taking it into the calculation, I got the feeling (before working out the math) that the significance of fuel burnt efficiency at plane take off will be reduced if I propose for the longer distance trip, let’s say instead of 1000 km but 6602km (Helsinki to NY JFK). In that sense, the take off period (10-20 minutes? Or depending on the height?) is significantly shorter compared to the normal cruise.

    3) I would agree that higher cabin factor (e.g. 70% vs 85%) would definitely reduce the CO2 emission per person per km from the very straightforward mathematic point view. The same would go to eliminating bussiness/first class seat and change it more economy class seat (which is also why I included Learjet bussiness jet – inspired by Chris Martin story by George Monbiot). However, I am not so sure about locos (new word for me, and I assume it means low cost airline like Ryanair/SAS?) in lowering carbon emission per person. And why? [to be continued...]

  6. May 21, 2007 at 6:29 am

    [...] I made when calculating CO2 emission for different type of aircraft/aeroplane in the previous post. I must admit that it was not a very detailed math work. I made very bold assumptions such as [...]

  7. rodney said,

    June 4, 2007 at 7:13 am

    so if i wanted to say carry 12kg of goods from hong kong to the uk how can i work out the co2 out put ?
    regards
    Rodney

  8. micpohling said,

    June 4, 2007 at 8:10 am

    Hi Rodney:
    well in your case, may be the different assumption like turning the passenger unit to become load in terms of kg is made. I think it is kinda complicated for me to calculate here because I made a lot of crude assumptions in my calculation, like Paul the reader above mentioned.
    Maybe your case would be close to the one which people say abt carbon mile for the goods, e.g. total goods/CO2 emitted during the trip.

  9. Simon Heath said,

    June 15, 2007 at 9:17 am

    Thanks for the work – it’s close enough for me to use in pub chat – the place where all the worlds most serious climate chat takes place :-) . I’m happy with a rough figure of 100g/km per passenger – you site comes close to to others I’ve seen working this out. Now I can argue properly – a trip to the south of France is best done by car (assuming your not driving a Landcruiser and there’s more than 2 of you) .It takes a bit longer but it’s less stressful if you don’t do too much in a day and make travelling part of the holiday. You can enjoy the scenery, and stop off along the way to enjoy some Degustation – burp. Leave flying to businesses I say – and start taxing it at the same rate as petrol!

  10. Jacob said,

    August 9, 2007 at 2:28 pm

    There is no consideration here of the release of CO2 at altitude. Studies have shown there to be a factor of around 3.5 for the damaging effect of high altitude emissions.
    We must remember not simply to consider CO2 and look at NO2 as well in the case of planes.

  11. mich said,

    August 9, 2007 at 3:25 pm

    Yeah, I have a brief look by googling at the CO2 impact by altitude. So far the one close to the claim is from wikipedia: The level and effects of CO2 emissions are currently believed to be broadly the same regardless of altitude (i.e they have the same atmospheric effects as ground based emissions) [http://en.wikipedia.org/wiki/Aviation_and_climate_change#Carbon_dioxide_.28CO2.29_emissions]. And according to this paper (http://www.gispri.or.jp/symp/pdf/ipccsym/sraa.pdf), it was more on the role of NOx impact onto ozone layer at different altitude (9-13km subsonic vs 17-20km supersonic) and therefore influencing the radiative forcing contribution from aviation.
    Another paper here from climatecare.org says that: Aviation emissions of carbon dioxide have the same effect on climate as terrestrial emissions, from power stations, industry or transport sources. Carbon dioxide has an atmospheric lifetime of up to 200 years, so ends up well mixed in the lower atmosphere over this timeframe no matter where it is emitted.(www.climatecare.org/media/documents/ pdf/Aviation_Emissions_&_Offsets.pdf, page 10).
    So summing up what I have searched briefly, I believe that there should be no impact of altitude where CO2 is emitted (CO2 is denser than air, and long atmospheric life, eventually CO2 will go down). However, you are correct in pointing out that it was other players such as NOx or air particulates released from aviation which contribute to overall positive radiative forcing, and roughly 2-4x higher than CO2 factor alone.

  12. P Ward said,

    August 28, 2007 at 10:48 am

    1) The altitude effect is not due to CO2 emissions as such, but to the warming effects of contrails. (There was a claim that the weather over the USA was much cooler after Sept 11th – especially at night – due to the grounding of aircraft.
    2) It is unfair to use emissions per passenger to compare private jets with commerical airliners. Very often the private jet is just “servicing” one person, so the figure for the Lear Jet emissions per passenger should probably be the same as the total emissions for the whole plane, as with John Travolta and his Boeing 707. (also David Beckham’s forthcoming trips: http://commentisfree.guardian.co.uk/derek_wall/2007/08/going_the_extra_air_mile.html)

    3) Is travelling by car to S of France better than using Eurostar & TGV (the latter is much faster, in my experience). A lot of the journey presumably uses nuclear electricity – how do we feel about that??!!

  13. micpohling said,

    August 29, 2007 at 3:04 am

    Hi P Ward:
    It was certainly a surprise to see my post had been linked by Guardian CiF. Afterall, I am just a layman (or gal).
    Anyway, as for your claim #2: I did not claim that private jet will definitely be serving 70% passenger capacity in order to get my *emission per passenger* number. As a matter of fact, I list out all (or as much as I could) the component: fuel consumption per distance and calculate the total CO2 emission for distance travel. From there on, you can calculate emission per passenger by dividing how many passengers as you like.
    As for point#3, I dont quite catch what you mean. But I guess travelling fast is not the only factor I am considering, e.g. I am living in Japan now, how should I travel to UK, if not by plane?

  14. HK environmental lover said,

    September 3, 2007 at 6:53 pm

    Hi all,

    as A380 has came to Hong Kong, China ,being a Hong Kong resident and environmental lover, I am finding information of A380 and has came across this website.

    A380 produces 75g of CO2 per passenger and per km.
    http://www.airbus.com/en/aircraftfamilies/a380/

    HK environmental lover

  15. quintessentquirk said,

    September 28, 2007 at 2:10 pm

    FANTASTIC POST!!

    I’m trying to work out the saving in CO² emmissions by not taking a bicycle aboard a plane, and instead hiring one at the destination.

    I’m doing this mainly because I run a green bike hire business here in Tenerife, and I’m trying to make the point about my business being eco-friendly… it’s the final point in my “Top 10 reasons to hire a bike instead of bringing your own”.

    I’ve searched and searched, but the trouble is, most consumption/emission figures are given in kg of CO² per passenger-mile. But what does the average passenger + luggage weigh? One reference said the average passenger weighs 77kg, but what about their average luggage weight??? HELP!

    And obviously you have to take into account the take off weigth of the place compared to the passenger load; if the plane flies empty, it still burns fuel.

    Assuming the bike +case weighs a total of 15kg, and the average flight is 5800km return (LGW – TFS), do you know roughly how much CO² will be saved by not taking one bicycle onboard one flight? I guess it is around 50 -100kg at most, but I’d like to be able to prove where I got my figures from…

    Thanks a million,

    So far I’ve come across two other sites that caculate fuel consumption:
    http://www.terrapass.com/flight/flightcalc.html
    http://www.tricoronagreen.com/tricorona/individuals_airtravel.php

  16. Paul said,

    October 19, 2007 at 8:43 pm

    Work on 35 kg of extra fuel per hour per tonne of weight. So that’s about 0.5 kg of fuel per hour per 15 kg bike, or 2 kg of fuel (or thereabouts) on a flight of that length. Though I’d be surprised if the normal bike and case is as light as 15kg. That’s about 12 kg of CO2 saved on a return journey.

    I don’t think that many people take bikes on holiday with them – you aren’t going to get much business by pitching it as an alternative to this, and in any case, the environmental benefits are hardly staggering. This is certainly a reason that ought to be well down your list!

  17. Ajay Shetty said,

    October 25, 2007 at 11:18 pm

    Hey guys,

    I am extremely to spot this webesite and particulary happy about finding so many expertise who are aware about .Co2 emission. can u guys pls help me about journals and articles which could help me in answering the question below.

    Imagine you are the CEO of a modestly-sized national airline (e.g. Aer Lingus, Icelandair, SAS).
    Your government has challenged you to come up with an outline strategy for the next 30 years
    on how you are going to maintain your operations faced with an expected 50% reduction in
    carbon emissions for the country as a whole. In order to meet its international obligations on
    climate change, the government will have to establish a ‘carbon budget’ (i.e. how much of total
    national carbon emissions are available) for each main industrial sector, of which aviation is one.
    Write a report (for the national Economy Minister) in which you:
    Outline how your airline will adapt to this new environment, including:

    A statement on what proportion of national carbon emissions should be allocated to the
    airline industry by an initial target date of 2025;

    Why aviation deserves this allocation, given competition from other sectors of the
    economy;

    How you intend to modify your business practices to adapt to this new operating
    environment (from where you fly, which aircraft you buy, your other procurement, to
    your pricing frameworks etc);

    What management processes you will put in place to make sure your targets are met.
    You are free either to pick a particular real-life airline as the basis for your case study, or to use
    an imagined, generic one (MBAir perhaps!). You should make full use of the available background
    information to the task available online, both in terms of academic research on trends in the

  18. Kudosdc said,

    November 8, 2007 at 11:19 am

    P Ward, you said: “The altitude effect is not due to CO2 emissions as such, but to the warming effects of contrails. (There was a claim that the weather over the USA was much cooler after Sept 11th – especially at night – due to the grounding of aircraft.”

    Actually, an examination of the three day period after 9/11 found that there was a statistically significant warming, not cooling. Contrails have been suspected to seed thunderstorm development, as well as a general increase in high level clouds. These clouds reflect sunlight back into space and tend to suppress surface temperatures. There is a good BBC Horizon/PBS Nova documentary that discusses this issue, along with other pollutants that may be mitigating some of the warming from the greenhouse gases. The fear is that we have been fooled by this masking effect, and may be underestimating the full impact of global warming. The name of the program was “Global Dimming.”

  19. John Buckley said,

    November 26, 2007 at 6:03 am

    Can anybody point me in the right direction to obtain data on CO2 emissions of small turbo-prop aircraft flying below 12,00ft? Thanks.

  20. Rajan Gupta said,

    December 11, 2007 at 7:44 am

    In the above calculations of fuel use by planes — I dont see the amount used in take off and landing which I believe are very significant. Is this included and if not what is it?
    Thanks
    rajan

  21. Nev Hill said,

    January 3, 2008 at 11:01 am

    How/where does one find the chemical reaction to JetA1 fuel burn, with all components & weights. With the burn there is the fuel & air (20% O2) plus a few other elements thrown in… & out we get CO2, plus H2O & other bits to make it all balance out.
    If the fuel bit is mixed with the O2 there has to be a lot of air used to get the resulting carbon & water residues.
    I’d really like to know how much of each it takes, as if the resulting CO2 is almost 3 times the weight of the fuel, plus the water, then what weight of O2 is in the equation.
    On other matters, JetA1 & JP5/7 have specific flashpoints therefore have an exact BTU value; the specific gravity is closer to 0.803 kg/ltr; a passenger & baggage weight is averaged 105kg per person, rounded to 100kg average for international services, thus a 20kg add-on (mountain bike) is 20% of the carbon footprint of a passenger over the same sector; a non-pressurised airplane flies at 10,000′ max; an average twin engined turboprop burns about 600lbs/hr (Kingair/10 seats or Twin Otter/19 seats). Finally are they planting trees to cover passenger carbon footprints & if so, what trees are being planted – does a Blue-gum in Australia convert the same amount of CO2 as a Pine in Canada of a generic tropical rain forest tree in Indonesia over the same growth period?

  22. Tony said,

    February 8, 2008 at 6:27 am

    Thanks for the great. I am trying to find data for the other plane, but it is not easy.
    Btw, I want to correct some data that you have posted. A320 can seat up to 164 in one class w/ 32in pitch. A321 is 199 seats in the same setting.
    For 737- 400, it have 159 seats w/ 32 in pitch and 168 seats w/ 30 pitch. For comparison, I think we should the same setting for all plane, so I use 159 for 737-400 and 123 seats for 373- 600.
    as the result, the CO2 emission per person per 1000km (70% full)as below:
    737 -400 = 84.097; 737 – 600 = 83.88; A320 = 79.70; A321 = 65.14
    For 747-400, the highest operating version is 569 in 2 class. It is operated by ANA.
    so the result is 76.922

  23. March 1, 2008 at 3:27 pm

    [...] Did you like this brief introduction? Find out about it in full detail here. [...]

  24. Dan P said,

    March 2, 2008 at 8:02 pm

    Hi, I’ve had a good read through all of this and am pretty impressed. I had been working something similar to this out myself. Can I ask where you got your data from regarding the fuel burn for the aircraft? Also does anyone know the fuel use data for the A330, A319 or Embraer ERJ 145?

    Also can anyone give links for sites similar to this with this kind of calculation?

    Dan

  25. michelle said,

    March 2, 2008 at 9:33 pm

    Dan,
    I just tried the google and nothing much more. You can check out the link from this post.

  26. George said,

    March 18, 2008 at 5:51 pm

    Great post! I’m trying to sum up some recent developments in green travel on my blog, and I was disappointed that most carbon calculators treat all airplanes as being equal.

    Your calculations are a good starting point for travelers considering which tickets they purchase produce the least CO2. But, I’ve found that there can be a pretty wide variance between different airlines and their CO2 output even when flying the same planes. For example, the 787 Dreamliner can be configured with anywhere from 759 to 780 seats depending on the desires of the airline that orders it.

    When you factor in optional electrical applications, number of crew carried onboard, and other factors, a plane’s performance can change pretty radically.

    ps; regarding Paul’s response: Wouldn’t all of the planes be affected by roughly the same fudge factor of take-off and landing efficiency?

  27. Drew Clarke said,

    August 5, 2008 at 9:52 am

    An excellent way of enabling ordinary people get a handle on how much they pollute when they go on holiday. One airline in the UK is putting rating lables on their aircraft (like white goods) not as much as I thought but of course the CO2 of consumption of services is always hugely difficult to comprehend – this page helps.

  28. Ronald said,

    September 22, 2008 at 7:56 pm

    I’m glad i’ve found your website, because there is to less info findable on the net.

    I wonder what the difference will be between planes and trains(if the train uses carbonbased electric power.

    I think the site you’ve found from SAS with the fueluse of the md90 is the take-off and landing included. Can that be the difference between the md-90 and the other planes you used in your calcutations?

    Keep up the good work

  29. Komali Rani.y said,

    February 11, 2009 at 5:31 pm

    Dear All,

    Very interesting and very useful website. Guys am doing a thesis on Impact of aviation on climate change in India. For that I need the CO2 emission factor for the commercial air craft in cruising. I got the emission factor for Landing-Take off cycles but am Struck up with the cruising factor. So if any one know plese help me out…

  30. Heey said,

    November 29, 2009 at 4:24 am

    This is confusin ! I need to know how much a regular airplane produces. For Carbon. Or what precentage, cars are responsible for global warming…


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