Loading ...
Sorry, an error occurred while loading the content.

10206Re: [carfree_cities] Metro in power failure

Expand Messages
  • J.H. Crawford
    Apr 5, 2007
    • 0 Attachment
      quick reply to Matt:

      >Thinking recently about emergency planning, it came to my mind: what
      >happens to a metro in a power failure? A few thoughts come to mind:
      >
      >- In Joel's carfree city prototype, what's the maximum number of metro
      >and metro-freight trains that would be in operation at any given
      >moment? What would the maximum power consumption be?

      say about 50 trains, 10 cars = 500 cars
      600 kW per car (max), say 150 kW average = 75,000 kW
      this assumes the high rates of acceleration proposed in the book

      >- In the event of a municipal utility failure, what happens with the
      >metro? Are the trains able to glide without power to the next station
      >to allow a total evacuation without making passengers walk through
      >tunnels?

      supercapacitors should probably be installed; these can store
      enough power to move trains into stations; they also help with
      regeneration

      >- Is an emergency diesel or NG generation system out of the question
      >for a metro to keep it running? My school has a roughly 80 kW propane
      >generator to run the elevator, fire pump, emergency lighting, phone
      >system, and intercom. I assume a metro would need _slightly_ more. *grin*

      Well, only about 1000 times more ;-)
      Actually, to keep the system operating in limp-along,
      probably 20,000 kW would do it.
      To put this in perspective, the largest diesel engines,
      used to power ships, are something like 75,000 kW each.

      >I'm assuming, though, that Joel's carfree city probably has all the
      >electric lines underground, reducing storm-related failures.

      absolutely!

      >By the
      >way, where would the metro's maintenance area be? In edge utility
      >districts?

      yup

      >BTW, for a city the size of Joel's prototype, would a dedicated city
      >power plant be called for?

      can't give a definitive answer; it depends on the power
      sources and where the energy supply is






      ----- ### -----
      J.H. Crawford Carfree Cities
      mailbox@... http://www.carfree.com
    • Show all 3 messages in this topic