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Electric locomotives on freight trains are pretty common in Europe probably because they can have a much higher power output in a smaller unit. A pair of TGV p

by willyt 6y ago

Electric locomotives on freight trains are pretty common in Europe probably because they can have a much higher power output in a smaller unit. A pair of TGV power cars, one at each end of the train, has a max power of 12MW at full acceleration, you would need about 14 of these diesel locos for the same output. The power here is 25kV at 50Hz apart from some commuter lines. Also modern electric trains can use regenerative braking to dump the braking energy back into the grid. It’s pretty common.

gpvos 6y ago
14 diesel locs for one TGV trainset; nice way of showing how energy-guzzling high speed trains are compared to classic trains. It's still better than an airplane, but not by that much.
- owenversteeg 6y ago
  Actually it is a heck of a lot better than an airplane. 14 diesel locomotives sounds like a lot, but that is absolute maximum power, and a TGV carries a ton of people. On routes where they are very inefficient (London-Paris as an example), you're looking at around 10 times more emissions by plane (plane 122kg vs high speed train 11kg.) On routes where they are efficient, you're looking at more around 100x more emissions by plane (65kg Paris to Lyon by plane vs 0.7kg by TGV.) Data here: https://ressources.data.sncf.com/explore/dataset/emission-co2-tgv/table/?sort=-tgv_empreinte_co2e_kgco2e_voyageur https://ressources.data.sncf.com/explore/dataset/emission-co... You'll notice that you can cross the whole of France, 1001km Lille-Marseille, for just about 1.6 kilograms CO2 per person per trip. Try that in a plane!
- willyt 6y ago
  Right but its pulling 12MW to accelerate you to 200MPH in a reasonable amount of time, it's not sitting at full power for the whole trip. I think they are capable of >300mph if you open it up to full power and see what happens. Also I got the number wrong a TGV duplex transports about 500 people with a max power of 8MW. A Eurostar is 750 people with max power of 12MW.

by willyt 6y ago

gpvos 6y ago

14 diesel locs for one TGV trainset; nice way of showing how energy-guzzling high speed trains are compared to classic trains. It's still better than an airplane, but not by that much.

owenversteeg 6y ago
Actually it is a heck of a lot better than an airplane. 14 diesel locomotives sounds like a lot, but that is absolute maximum power, and a TGV carries a ton of people. On routes where they are very inefficient (London-Paris as an example), you're looking at around 10 times more emissions by plane (plane 122kg vs high speed train 11kg.) On routes where they are efficient, you're looking at more around 100x more emissions by plane (65kg Paris to Lyon by plane vs 0.7kg by TGV.) Data here: https://ressources.data.sncf.com/explore/dataset/emission-co2-tgv/table/?sort=-tgv_empreinte_co2e_kgco2e_voyageur https://ressources.data.sncf.com/explore/dataset/emission-co... You'll notice that you can cross the whole of France, 1001km Lille-Marseille, for just about 1.6 kilograms CO2 per person per trip. Try that in a plane!
willyt 6y ago
Right but its pulling 12MW to accelerate you to 200MPH in a reasonable amount of time, it's not sitting at full power for the whole trip. I think they are capable of >300mph if you open it up to full power and see what happens. Also I got the number wrong a TGV duplex transports about 500 people with a max power of 8MW. A Eurostar is 750 people with max power of 12MW.