Car vs. Plane: Which Has Bigger Effect on Emissions?

By | August 2nd, 2005 10 Comments

carplane.jpgThere’s been a lot of talk about the high amount of greenhouse gas emissions put out by aircraft lately. I wanted to find out if airplane travel really is worse than automobile traffic, on a per person basis. This is the document I stumbled upon.
According to the FAA, including idling and taxiing, an airplane gets about 48 miles to the gallon per seat. That’s a heck of a lot better than I’d thought, though it obviously depends on a myriad of other factors: Long flights are more efficient, newer planes are better. But a rule of thumb suggests that traveling solo in an SUV is probably more harmful in terms of emissions than buying a plane ticket, but carpooling, even in an SUV, is probably better then flying.

10 Comments

Categorized: Climate Change|

  • http://taestell.cjb.cc/ taestell

    That’s a surprisingly low number. People are going to fly in certain situations anyway, since a cross-country flight may take 9x less time than driving the same distance, so it’s good that planes are as efficient as they are.

  • http://www.d4v3.net Dave

    Interesting that there are actual numbers we can use to begin calculating this sort of stuff. Two things I noticed, however:
    Distance: It sounds like it’s better to drive four people across the US in an SUV over five days than it is to fly them across the US in six hours. And ultimately it sounds like an apples-to-oranges comparison, 1) because you can’t drive a car across the Pacific Ocean, and 2) because airplanes typically fly greater distances than cars travel (in the course of commuting, for example).
    Location of emissions: SUV emissions are close to the ground, while airplane emissions range from close to the ground to high in the atmosphere. It’s not just the emissions themselves, but the effects they have at various altitudes that are important.

  • Travis

    Your discussion begins by talking about emissions but then quickly turns to mpg. Knowing mpg numbers isn’t the most effective way to understand the impact of the actual emissions (and as Dave pointed out – the location is important as well)

  • Sara Henningsson

    Guys, guys…this is such a biased article! It is quoting not only the Federal Aviation Administration which i would not be too surprised to hear had good reasons to underestimate the miles-per-gallon-per-seat numbers but also one of the oldest lies in the book about environmental impact. Namely: “…you could argue that the plane flies anyway, no matter if you are on it or not”. I am sure you all must see the lack of logic behind such a statement?! It is exactly the same rational as if you were going to buy body-parts of endangered animals from poachers because “you might as well as the animals have already been killed”. Obviously, if people stopped flying several times a year and taking the car (low-energy cars or preferably the train!!) instead of a flight on within-continent trips, then the plane wouldn’t be flying “anyway”. They don’t fly planes that have no passengers! (granted, the article also makes a short remark on this afterward which makes you wonder why they would even have made the twisted statement in the first place if not to mislead the reader).
    Surely, you all agree on this??

  • Sara Henningsson

    Here is another “article” and it has a link to a “carbon-emission calculator” where you can compare the emissions on an anticipated journey of yours with your car versus with an air plane.
    http://www.grist.org/advice/ask/2007/10/17/

  • Anonymous

    If cars produce 35% of greenhouse gasses adn aircraft produce 1-3%, where do you think our efforts should go?

  • Anonymous

    efforts should go into something more productive than thinking about this stuff.

  • mackenzie

    your information is great and i kind of figured that the airplane would put out more then the car but you setteled that for me so thank you for the info

  • znoop72

    But cars have effective emission control system. Catalytic converters ( reducing C0, Nox and HC emssions ) . An EGR system that greatly decreas Nox emmissions. EVAP (ford) systems that further decreas HC emmissions. Not to mension the ” new” Diesel common-rail and active particle fitration systems on mainly european cars. Most europeans drive diesel.
    Do airplanes have emission systems at all? It seems to me that they just leave alot of untreated exhaust in the air. Is this true? In that case we should be talking about co2 or mile or hr.
    Just throwing some ideas out here.:)

  • znoop72

    But cars have effective emission control system. Catalytic converters ( reducing C0, Nox and HC emssions ) . An EGR system that greatly decreas Nox emmissions. EVAP (ford) systems that further decreas HC emmissions. Not to mension the ” new” Diesel common-rail and active particle fitration systems on mainly european cars. Most europeans drive diesel.
    Do airplanes have emission systems at all? It seems to me that they just leave alot of untreated exhaust in the air. Is this true? In that case we should be talking about co2 or mile or hr.
    Just throwing some ideas out here.:)