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New Study Suggests Flying Is Greener Than Driving
New submitter Desert Leap writes: The Washington Post reports a new study that suggests it is more environmentally friendly to fly rather than to drive. Analysis from the University of Michigan Transport Research Institute found that driving uses 57% more energy than flying per passenger mile. This is largely due to the number of occupied plane seats increasing while passengers per car decreased. Of course, "results may vary" for individual trips depending on many factors, such as distance flown (long flights are more fuel efficient) and the kind of car, and how many riders. One factoid is interesting: it takes 4,211 BTUs per person mile to drive. This number will fall as we switch over to electric vehicles. For example, a Tesla Model S takes about 1,100 BTUs per vehicle mile. Will future aircraft be able to also make the switch to electric?
This depends where you are. In many cities buses run full regardless of the time of day. Even when ridership does decrease the reason that bus companies do not switch to minivans is that the most expensive part of operating a bus is the driver. Switching to smaller vehicles does not save a transit authority enough money to justify the logistical nightmare involved in changing vehicles while a route is in operation.
Just because you are paranoid does not mean that no-one is out to get you.
The comparison between planes and other modes of transit would be for longer-haul routes since planes do not provide inter-city transport. For longer routes, buses normally run fairly full. And for those that say buses aren't always full, I have been on a 737 plane between cities 1000 miles apart where there were only four passengers, including me, and on a flight to the far east where I had a row of five seats on a 747 all to myself for 12 hours.
I remember some years back that the Ford Excursion Diesel was rated one of the top most fuel efficient vehicles. The caveat was that you had to fill all 9 seats with people. If you did that, your economy per passenger was better than just about every car out there, even a Prius with a full passenger load. Of course, I would usually only see one or two people in them on the road so the real world figures weren't as good as that. But the point being made was that bulk transportation of people was more efficient than individuals driving cars.
But that also underlines another point..
We really didn't need another very expensive study to tell us the very obvious. Of course flying is more efficient than driving, so long as everyone is going from the same origin to the same destination on a direct flight.
One of the things I'm pretty sure they didn't factor in was how far people had to travel to get to the airport before the flight and how far they had to travel to get to their destination afterwords, not to mention what type of transportation they used. Certainly, if you're driving from one airport to another the model holds true. But the farther away from the airport you are before and/or after your flight, the more the numbers can skew. And I'm pretty sure they don't factor in when you have to fly through a hub airport that takes you hundreds of miles out of your way. So if you got a deal on a United ticket and you have to fly from Iowa through Denver's hub on your way to Orlando, I'm pretty sure any fuel efficiency you would have gained on the airplane is negated by the fact that you're going something like 1,500 miles farther than you would have on the drive.
Fair enough. I was working from memory, couldn't remember where intercity busses fit in the mix and was too lazy to try to find it. I stand corrected. The TRBs TCRP 79 reports the average energy consumption for intercity buses as 713 BTU/(passenger mile). As such, the revised hierarchy ought to be:
I don't know if you're being funny or serious, but that's a common misconception so I'll assume you're being serious. The CO2 and methane that we animals spew all came directly from the atomsphere through the food chain or through breathing. It's a closed cycle - plants and animals take CO2 from the atmosphere, store it a short while, then release it back into the atmosphere. That closed cycle is the gold standard of sustainability, pretty much the opposite of "non-green".