Rail Users Ireland Forum - View Single Post - [article] RPA defends capacity of proposed metro trams

MrX · 16-02-2008, 11:26

I'm not sure how Madrid is suddenly comparable to Dublin as a city?!
The Madrid metropolitan area contains 4 858 000 people and Berlin's got >3.7 million!

Munich, Frankfurt, Leeds, Lyon, Porto, Copenhagen, Stockholm, Saville, Glasgow and Marseilles are more comparable to Dublin

http://en.wikipedia.org/wiki/Largest...European_Union

On the capacity issue, installing something grossly below capacity would be completely nuts, but at least it would be in line with normal Irish planning policy which has been used for everything else .. M50... ?

Also, whether it's 3rd rail or overhead wires really makes no difference. Plenty of other modern metros use overhead power, including many of the major Spanish cities' systems. There's basically a bus bar at the top of the tunnel, it doesn't take up very much space. When the train's in the tunnel, the pantograph (contactor on top) is folded almost completely down and just scrapes along the ceiling. When it's above ground, the system's more like the DART or Luas. It's safer, and really not a huge issue to implement. 3rd rail's generally only implemented in extensions to old systems and has a lot of safety and maintanance disadvantages. They don't comply with modern (post 1950s) electrical safety legislation but are "grandfathered" in countries that had significant 3rd rail infrastructure since the turn of the 20th century as it was simply too complicated and too costly to replace.

I don't really see 3rd rail or overhead power being much of an issue, the issue is the capacity of the trains and the future-proofing of the tunnel(s)

16-02-2008, 11:26	#19
MrX Really Regular Poster Join Date: Dec 2005 Posts: 585	I'm not sure how Madrid is suddenly comparable to Dublin as a city?! The Madrid metropolitan area contains 4 858 000 people and Berlin's got >3.7 million! Munich, Frankfurt, Leeds, Lyon, Porto, Copenhagen, Stockholm, Saville, Glasgow and Marseilles are more comparable to Dublin http://en.wikipedia.org/wiki/Largest...European_Union On the capacity issue, installing something grossly below capacity would be completely nuts, but at least it would be in line with normal Irish planning policy which has been used for everything else .. M50... ? Also, whether it's 3rd rail or overhead wires really makes no difference. Plenty of other modern metros use overhead power, including many of the major Spanish cities' systems. There's basically a bus bar at the top of the tunnel, it doesn't take up very much space. When the train's in the tunnel, the pantograph (contactor on top) is folded almost completely down and just scrapes along the ceiling. When it's above ground, the system's more like the DART or Luas. It's safer, and really not a huge issue to implement. 3rd rail's generally only implemented in extensions to old systems and has a lot of safety and maintanance disadvantages. They don't comply with modern (post 1950s) electrical safety legislation but are "grandfathered" in countries that had significant 3rd rail infrastructure since the turn of the 20th century as it was simply too complicated and too costly to replace. I don't really see 3rd rail or overhead power being much of an issue, the issue is the capacity of the trains and the future-proofing of the tunnel(s) Last edited by MrX : 16-02-2008 at 11:28.