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The old one did around 20kWh/km and they claim 32% less CO2 per passenger. Perhaps including the construction too, but that shouldn’t change a lot.

So let’s say 14kWh/km (or about 8 times the recommended food energy per day for an average person, per mile).



That actually seems like an awful lot...

A tesla model 3 is 250 wh/mile. so 56 cars energy = 1 trains energy.

The train has steel wheels (far lower rolling resistance) and a far more aerodynamic shape... But also has the downside of far more weight, probably less efficient motors and power electronics, limited regen ability, and faster speed (air losses are the third power of speed)


The train also has 740 passengers. 56 Tesla model 3 could fit 280 people (a bit tight in the middle back seat).

And yes, the model 3 cannot average 300km/h. Still it shows that trains could be better.


> 56 cars energy = 1 trains energy.

These trains accommodate around 500 passengers though, while a car is generally max 5 passengers.

So the trains are about ten times more efficient, and two to three times as far.


And an average tesla does not have 5 ppl in it, from what I can see its more like 1.5, whereas you typical train seems to be 60% full (personal experience).


Each TGV seats 500-700 people, about 100 to 500 times better than you RR average model 3. And goes a lot faster. I'd be curious to know the M3's mileage above 300 kph.

I thought regenerative braking was a strong point of trains? The motor is probably of comparable efficiency, I expect power electronics to be worse, indeed.


The train is capable of regen braking... But frequently the infrastructure is not. A train braking can be many megawatts of power, something that can't be dumped on the electricity grid of a small town without a bit of planning in advance.

So, where capacity to dump the power can't be certain, regen braking isn't done, or is at least limited.


This sounds like a great application for supercapacitors. Regen charge the caps when braking to enter a station, and use that energy to accelerate back out of the station


A 400t train at 300km/h is a gigajoule or two.

That's a decent chunk of the weight of the train in capacitors.


> A tesla model 3 is 250 wh/mile. so 56 cars energy = 1 trains energy.

Do that calculation again with 12 people in the tesla and have it moving at over 300km/h on average.

Don't forget to include the 30 sets of tyres per 8hrs of driving and a new battery every 100-500hrs




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