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0 pointsdarkmighty7y ago0 comments

Moreover, if power becomes significant you can add regenerative breaking to regain a large fraction of energy (if they're not doing so already; maybe not because of the age of the trains).

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lathiat7y ago

The London Underground definitely does that. Also in part because it reduces the heat output. The underground has been heatsoaking for decades and it’s hitting problematic temperature levels.

This article is a great read: https://www.ianvisits.co.uk/blog/2017/06/10/cooling-the-tube...

Apparently about half of the heat generated in the tunnels is/was from braking. And the tunnel temperatures have risen from 14-30C since around 1908.

Is a good read about the engineering challenges.

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