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A comment on Paris said au revoir to cars. Air pollution maps reveal a dramatic change. Parent comment

Re:Paris said au revoir to cars. Air pollution maps reveal a... by philjohn on Saturday April 12, 2025 @05:28PM (#43668085)
most subway trains are decades old - newer fleets have regenerative braking[1]

But also ... almost a century of brake dust because nobody is going through and vacuuming the tunnels.

[1] https://tfl.gov.uk/corporate/transparency/freedom-of-informa...

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Re:Paris said au revoir to cars. Air pollution maps reveal a... by cogman10 on Sunday April 13, 2025 @11:43AM (#43673600)
Interesting. Looks like it the line isn't able to take the energy (I'm guessing voltage is already too high) they dump the energy into a resistive heater.

Makes sense, it's just going to be heat anyways. I wonder how often that happens vs the energy getting dumped into the line.

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