TRAINS, PLANES, or AUTOMOBILES? - Which uses more energy and leaves a larger carbon footprint?

Question

Please help settle a debate between my friend and me.

She's convinced taking a large series of trains from Hong Kong along the transSiberian route all the way to England will produce less energy output than a single flight.

I think it's counter-productive considering there's no straight route.

I'm having difficulty finding supporting information... but so it she.

I don't mind being wrong. I just want the facts to support the answer either way.

Answer 1

I'm not sure whether in Charles C's excellent answer the implications of fuel and refueling were all clear.  Airplanes, although they don't stop to refuel (thus losing some efficiency) have a bigger problem because they have to carry all the fuel they need for the entire flight, plus a reserve for emergencies (as having to circle the airport while waiting to land or even going on to another airport).  As we know, the more weight they carry, the more fuel they burn (that is why some airlines are charging for luggage; I also read that one airline was saving significant fuel by using lighter serving carts!).    The fuel a 747 carries at takeoff weighs more than the passengers, the crew, and all their luggage combined.  See these "747 Fun Facts":  

    * The 747-400ER can carry more than 63,500 gallons of fuel (240,370 L), making it possible to fly extremely long routes, such as Los Angeles to Melbourne, Australia.

    * A 747-400 that flies 3,500 statute miles (5,630 km) and carries 126,000 pounds (56,700 kg) of fuel will consume an average of five gallons (19 L) per mile.

    * The 747-400 carries 3,300 gallons (12,490 L) of fuel in the horizontal (tail) stabilizer, allowing it to fly an additional 350 nautical miles.

A gallon of "gas" (actually I think it's kerosene) weighs about 8 pounds.  

Of course the plane burns fuel as it goes, so it does not carry all the weight to the end, just the reserve (assuming that was not needed).  Thus short flights are somewhat more efficient than long ones, because the plane will start out with only as much fuel as needed.  A 747 at the halfway point between San Francisco and London will still have about as much fuel as one just starting out in New York for a flight to LA.  

I read on one UK site that coaches (buses) are most efficient; there was no explanation, but I am guessing it's a matter of weight, both vehicle and fuel being much lighter than with train or plane.

Answer 2

Don't base your decision on your "carbon footprint". That's all a load of rubbish. The CO2 that man produces only accounts for a very small percentage of the CO2 in the atmosphere (about 3% if that). 95% of CO2 in the atmosphere comes from water which is releasing more CO2 as the planet heats up naturally, as it should every few hundred years.

Answer 3

You could go the simple route. The cost of the trip (how much is the ticket) can be a good scale, If their costs goes up, the price goes up.

Another idea is to ask yourself how often you hear about a train stopping for re-fueling. Now how about planes?

OK, Now let's think about starting and stopping. A plane has to get up to a high rate of speed very quickly in order to take off (unless the airport is just huge beyond reality). A train is generally slow to take off so the train wins fuel efficiency there.

When landing planes generally reverse thrust to slow down, this takes more power. Internal combustion trains use air brakes when stopping. they are far more efficient, and they tend to use them very little, letting the train slowly lose momentum. Electric battery powered trains generate electricity while stopping. This re-charges the batteries. Electric trains using either over-head wires, or the third-rail system use electric brakes, but they are more efficient than using reverse thrust on a jet engine.

Jet engines are normally not ran under peak load except when taking off. Trains generally are. Running an engine at peak load increases the fuel efficiency.

The train has to continue traveling whether there are passengers or not because they carry cargo also. They make frequent stops to pick up passengers and cargo, and drop off the same. Take away some points for that. If there are few or no passengers on a jet, it's flight will probably be canceled, and the few passengers and such will be put on another plane later.

Give them points back now because often in bad weather a plane will end up sitting near the runway for a long period of time waiting clearance to take off. Trains are not affected by rain, sleet, or wind. Snow and ice they will plow through effecting the efficiency, but remember them planes are sitting their running and waiting.

Now is where we hit some points that you might never have thought of. It takes huge amounts of energy to build a plane...as does it take similar energy to build a train. A plane though will be retired from use before it is wore out, or becomes un-reliable. This is not the case with trains because a train breaking down is nowhere near as much of a safety hazard as a plane breaking down is. This is where a plane loses the battle for efficiency really quick.

So, you want your trip to have less of an impact on the environment? Well if you take a train, there's a chance that the flight might get canceled. The train will travel on though wether you are on it or not.

Answer 4

cars make the most then trains then planes.

Answer 5

She is right  and you respect her dicision but it is contrasting to say that do not be environmentalist with CO2 only trains have a lot distrubance that they cause to environment which is just with you planes may be polluting air with Co2 which is recycled back also by trees and other vegetation but the train if it is electric then may cause some electromagnetic disturbance which may be enough to change genetic constitution of some organisms living near tract

Answer 6

When moving large amounts of cargo trains are most efficeint, then autos and finally planes, although most planes get 50 passenger miles per gallon.    Ships are most efficient overall.    

Forget about the carbon footprint.   That's a chance of a lifetime to take a journey like that.

Answer 7

Planes is most polluting.

North America(America and Canada) should learn from europe and use high speed rail roads. High speed trians are powered by electricity which is clean.

North america is even behind India and China in rail roads.

Trians in China are all powered by electricity and china is currently building a high speed rail road connecting Bejing and Shanghai.