Barcelona is turning subway trains into power stations

Comments

• JasonDJ@lemmy.zip ⁨1⁩ ⁨month⁩ ago

  Are they generating more power than they are spending by making the train go? Has Barcelona mastered perpetual motion??

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  • GamingChairModel@lemmy.world ⁨1⁩ ⁨month⁩ ago

    I don’t read it as magical energy created out of nothing, but I do read it as “free” energy that would exist whether this regeneration system is used or not, that would otherwise be lost as heat.

    With or without regenerative braking, the train system is still going to accelerate stopped trains up to operational speed, then slow them down to a stop, at regular intervals throughout the whole train system.

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    • JasonDJ@lemmy.zip ⁨1⁩ ⁨month⁩ ago

      Only because of the speed of the train. Fuel spent accelerating to later brake is wasted fuel. More efficient would be spending only enough fuel to come to a full stop without braking.

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• Ilovethebomb@lemm.ee ⁨1⁩ ⁨month⁩ ago

  Regenerative braking on commuter trains is nothing new, it’s been around for decades.

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  • nightwatch_admin@feddit.nl ⁨1⁩ ⁨month⁩ ago

    Agreed, but here it is done highly effective. The 1.8 degree temperature difference is a huge plus too - they can now also save serious amounts of power on ventilation.
    TfL, you listening?

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    • guy_threepwood@lemmy.world ⁨1⁩ ⁨month⁩ ago

      Victoria, Circle, District, Hammersmith and City, Metropolitan and the new Piccadilly Line trains (due soon) all have regenerative braking. The rest will follow as new trains are procured.

      As anyone who travels on the Victoria line in the summer will tell you: it helps, but not much.

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  • pirat@lemmy.world ⁨1⁩ ⁨month⁩ ago

    And even in some prototype bus, the Gyrobus, in the 50’s that used an electrically charged flywheel that was also (to some degree) regeneratively recharged when breaking:

    Rather than carrying an internal combustion engine or batteries, or connecting to overhead powerlines, a gyrobus carries a large flywheel that is spun at up to 3,000 RPM by a “squirrel cage” motor.[1] Power for charging the flywheel was sourced by means of three booms mounted on the vehicle’s roof, which contacted charging points located as required or where appropriate (at passenger stops en route, or at terminals, for instance). To obtain tractive power, capacitors would excite the flywheel’s charging motor so that it became a generator, in this way transforming the energy stored in the flywheel back into electricity. Vehicle braking was electric, and some of the energy was recycled back into the flywheel, thereby extending its range.

    Source: Wikipedia: Gyrobus

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    • Ilovethebomb@lemm.ee ⁨1⁩ ⁨month⁩ ago

      That’s incredible.

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    • Skunk@jlai.lu ⁨1⁩ ⁨month⁩ ago

      Nice, it’s probably the ancestor of the TOSA which is the same thing without the flywheel.

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  • scarabic@lemmy.world ⁨1⁩ ⁨month⁩ ago

    It is, though, as the name of the community implies, “technology.”

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• catloaf@lemm.ee ⁨1⁩ ⁨month⁩ ago

  It also reduces brake wear on the trains, so they’ll need new brakes less often, and it improves air quality in the stations. Most of that black dust you see is brake dust. And you’re breathing it in, too.

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• thenewred@lemmy.world ⁨1⁩ ⁨month⁩ ago

  Why can’t they use the excess energy to make the train go again?

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  • doczombie@lemmy.world ⁨1⁩ ⁨month⁩ ago

    They do… 1/3rd of it is used that way.

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