Midland Metro Expansion

[edwin_m]

The Rotherham trial is to test out the economics of tram-train running as well as the technical issues. If the running costs are significantly lower, and patronage could be increased through higher frequency services, then I can see them being used as Pacer/153 replacements on some lines. The minimum length of a single new EMU will be 3x20m and would be merely a short Desiro City or Aventra product, which will likely be too long and expensive for some of the more marginal branch lines in the country in the short term.

Tram-trains would reduce the expenditure needed to increase services as heavy rail infrastructure is now so expensive. Extra heavy rail services might need expensive new loops, 25kV AC electrification and for level crossings to be replaced with more expensive versions or bridges. Tram-trains don't require this, and as I said they could be used to reopen lines which have been closed and their alignments partly built over which would be uneconomical to reopen to heavy rail standard on a segregated alignment without level crossings. Tram lines themselves don't require the same clearances or weight requirements as a new heavy rail line so there might not need to be any expensive tunnel or bridge works required to reopen these lines.

I agree with you on reopenings but not on existing lines.

On existing lines there might be a marginal saving in power consumption and track wear but it won't be a dealbreaker. The big saving would be from DOO, but the benefits and problems of that would be exactly the same with a new conventional train.

750V electrification isn't any cheaper than 25kV - on a railway either would need clearances enlarging and feeding all the substations gets more difficult on a more rural route. The power losses at the lower voltage increase too. There is also the risk of extra conversion cost if 25kV is ever needed, which Sheffield is minimizing by using 25kV equipment where possible and buying dual-voltage vehicles.

Stadler's GTW shows that a shorter EMU is possible - this isn't a tram-train but has some of the features that might benefit reopenings. In my view something like this will be the way forward when we finally have to buy some new trains for rural routes.