The A380 arrived in the U.S. today. The plane can carry 81,890 gallons of fuel and flies 8000 nautical miles, i.e., it burns approximately 10 gallons of fuel per nautical mile or 9 gallons per statute mile. The plane can seat 850 people if configured as an all-economy ship, so the mpg per person is approximately 95 (assuming the plane is fully loaded, which most planes seem to be these days). The Prius gets around 45 mpg in real-world driving and, though it can seat 5, is typically occupied by one person.
[I once saw an analysis of overall per-passenger-mile transportation cost, including capital investment and labor costs. The Boeing 747 was the cheapest form of transportation, period.]
Not only are large jetliners more efficient, they can get you from anywhere to anywhere on Earth in less than a day, assuming there’s a runway in both places.
But I find it hard to swallow that it’s cheaper than walking. As has been pointed out elsewhere (http://www.sightline.org/daily_score/archive/2006/04/19/dead-man-walking), given reasonable assumptions, you actually create (rather than consume) time when walking.
Then again, a meat-powered human on a bicycle may generate more CO2 than the same human in an SUV (http://www.csmonitor.com/2007/0220/p03s01-ussc.html).
That doesn’t even take into consideration the fact that most planes fly straighter lines than cars can drive. If you were to factor that in, and the time spent idling at a stop light, the 747’s mpg would diminish the Prius even more.
While it is true that a fully loaded modern airliner has a fantastic mileage per passenger mile and has contributed to cheap airfares it is not fair to compare a fully loaded airliner to a car with just the driver. I know people who use a Prius to carpool and using your 45 mpg that results in 180 miles per pax mile. That is the ultimate comparison. Once you have mpg/seat and filling seats separated you can go into ideas for getting those empty seats filled. The airlines sure work hard at it; if the general population worked half as hard at it there would be phenomenal oil savings.
since most people don’t have an A380 parked in their driveway one needs to drive a Prius to the airport, partially skewing the amazing mpg figure. Sounds like a vegetarian walking all the way from home to the gate might be most efficient. BTW Airbus claims a fully loaded three-class A380 is five times cheaper per passenger than similarly configured 747.
Apples to oranges compairson, Phil. If you use figures for a full A380 at max seating configuration, you should do the same with the Prius.
Or, for a real-world scenario, compare the typical Prius (1 person) to the typical Airbus A380. The problem is, nobody’s going to operate the A380 in single-class configuration. The launch customer, Singapore Airlines, is using a ~450 seat configuration. Quantas will be in that ballpark, too. Also, the airplane will probably not be full all the time, which reduces the mileage figures somewhat. If you figure 420-440 people on average, you’d probably be in the ballpark.
When doing this comparison you need to remember time in the equation. Even at 42 mpg per person, that gallon per person moves that person 42 miles in about 5 minutes whereas the Prius will do it in about an hour on average or maybe 45 minutes on a long trip. You factor in things like hotels enroute, productive time lost, food and other expenses of a long trip, the airliner will beat the Prius hands down. Another plus is that unlike the car, you only pay for the airliner when you need it.
I don’t even want to think about how a turbine single rates. Naturally, passenger-miles are really only fair comparisons when you’ve got that many people all wanting to go from the same place, to the same place, at the same time. Obviously southwest is pretty efficent at running their business, and it’s not unusual to spend 100 bucks flying from Oakland to L.A. I imagine that the taxicab industry is also pretty efficient at pricing. (and if not taxis, certainly the airport shuttle business) It’s not unusual to spend 40 bucks on transportation to get where I’m really going at each end. From the point of view of dollar/miles, the airplane is worlds better than the taxi or shuttle, but it really doesn’t matter, because the airplane won’t go where you need to. (It’s sort of the physical analog to the “last mile” problem that used to plague the internet) That’s one reason I think the people that think there’s going to be a huge market for “Air Taxis” once the million dollar jets finally come on the market are just wrong. There just aren’t enough small airstrips in places people want to go to make it worthwhile. While getting shuttled into TEB is probably awesome compared to the feedlot-like conditions a commercial passenger endures arriving at newark, TEB is apparently so choked with 6-15 million dollar private jets that there isn’t much room for a bunch of air taxis to be popping in and out. Apparently, once you’re there, you still need to figure out how to get into the city. It’s the same here in the San Francisco bay area: despite a fairly good number of them, even the smallest airports don’t tend to be where most people need to go.
“I want my flying car”! (I’ve almost given up on flying from the bay area to southern california: 30 minutes to the airport, 90 minutes waiting, 15 minutes in the aircraft on the ground waiting some more, at least 60 minutes in the air, 15 minutes to get off the plane, 20 minutes to get your bags, 10 (minimum) to arrange some kind of ground transportation, and 30 (minimum) to get where I’m going is about 4.5 hours. It’s a little over 6 to drive)
I think the “Air Taxis” will fill in some of the routes that don’t have the demand to satisfy today’s carriers. For instance, BOS to JAC. There are plenty of people from Boston and NYC who want to get out to the Jackson area. On existing commercial carriers, it’s expensive and a long flight (watch out for layovers in Houston and Atlanta). I’m convinced somebody could fill a smaller jet on a non-stop flight on this route. Same goes for BOS to TEX or EGE.
The Economist ran an article on CO2 emissions from aircraft in its 8 June 2006 issue.
I think the biggest fuel economy/environmental impact problem with commercial airliners is that they are so fast and convenient that they encourage additional trips. It is true that I will consume less oil by going to Los Angeles on a jetliner than by driving in a Prius, but I am a lot more likely to make the trip on JetBlue than I would be to drive any kind of car for five days. In the old days, nobody went to Europe more than once per year since sailing across on an ocean liner took so long. Now plenty of people will go to Europe 5-10X per year for business and pleasure (what could be more fun than paying $5 for a Diet Coke?).
Total cost analysis is hard to do, but most of the figures I have seen suggest rail as the winner, though they were not accounting the cost of the land. It’s certainly the energy winner — low rolling resistance, and big long trains slipstreaming against the largest cost of energy in travel, namely air resistance.
The figure given more a typical aircraft is about 50 pax-miles/gallon. When I tell people this it actually shocks them in the reverse way. They assume it’s much more efficient than that. Effectively they are learning that flying to the other coast — which we do so casually, burns a similar amount of fuel to driving there, 2 people in a typical car, which they would think of as fuel-extravagant.
As efficient as the 380 might be, the truth is these vehicles encourage us to make much longer trips. I drive about 10,000 miles per year but I fly 25,000 to 30,000 and this is not uncommon. For a large number of people, their jet flying will be the lion’s share of their emissions contribution.
Probably also important to consider the impact of energy consumption and CO2, etc. production by the support infrastructure for the airplane. The airports at both ends create a certain environmental load as does the transportation system in and out of, and within the airport.
To be honest, you’d have to also consider additional associated costs for the Prius.
It is interesting to think about the non-obvious environmental costs of things. I’ve often wondered whether it makes more environmental sense for me to drive my decent mileage small car to visit relatives 900 miles away or fly and rent a car when I get there.
A couple comments:
– planes consume much more energy when they’re taking off than when they’re in steady-state flight. So a typical 3500 mile new york to london route is going to be a lot less efficient than an 8000 mile route.
– energy consumption does not equal environmental impact. Unlike cars, planes have no emissions controls, and release their exhaust directly into the upper levels of the atmosphere.
Not only are aircraft seldom completely full (even to the real-world configurations where they generally have far fewer seats) — I’ve flown in 7×7 flights with less than a dozen passengers, but they didn’t cancel the flight because that piece of hardware was necessary for the next leg — their is significant empty-aircraft shuttling that occurs to fulfill service levels.
You have failed to mention that Co2 released at altitude has a radiative forcing effect twice that of co2 released at ground level.
To counter daves point on the efficiency of a 3500 mile flight vs 8000, while taking off does consume more fuel, the max efficiency gain tops out at about 3500 miles, since flying longer than that means carrying large quantities of heavy fuel, which hurts fuel economy.
I encourage everyone who posted comments that are pro air traveling thoroughly read the June 10, 2007 Economist article, The Sky’s the Limit – Aircraft Emissions. Some text of that article has been quoted on this blog, but that does not give you a full picture of the impact of air traveling, which the author intended to articulate.
As someone has already pointed out, the fact that cheap flights are available, means that people will use them. Just because they are available, does not make it morally correct to use them, whether or not they are more or less efficient than other forms of transport.
Take the example of nuclear impulse rocket engines. They are acutely ‘dirty’ and dangerous so we use other forms of rocket engines. The problem with air and car etc. transport is that they are chronically dangerous so we stick are heads in the sand and pass the problem to the next generation who will say, “what were they thinking of!”