I agree, but because of cost only the main route via Huddersfeild will be electrified in all probabilty. That means Bi-mode or deisel under the wires remains, as well as the issue of diversions. If for the same cost you could cover all the remaining routes, i.e Calder Valley as well as Leeds Bradford Interchange then you might be better off, but I agree it will not happen
I think the real mistake was not building the Thameslink core as a four-track section when Holborn Viaduct was demolished. You would then have had a City Thameslink with 4 platforms. The Crossrail rebuild of Farringdon was another missed opportunity, as it was a prime opportunity to build more platforms to the west of the tracks where rails once ran and link through to Smithfield sidings.
And yet the whole of the National Rail 3rd rail and London Underground systems can carry on as they are? Things are either acceptable, or they are not.
I thought the DLR was a bottom-contact system? With the shielding, it's very hard to touch the live contact. Of course, changing to a bottom-contact system would be effectively impossible to do in a phased manner from the top-contact system in place.
It is bottom contact - and by many previous accounts it just doesn’t scale up to mainline speeds and high current requirements.
Indeed.
Spot on limiting factor we had on SR electrification schemes was we had access to one LWRT which can hold 3200Yds of 150lB of conductor rail. Easily unloaded in an overnight possession and installed over the next four nights but we could have gone faster had we access to more LWRTs but they had to support running rail drops as well.
Electricity at Work Regulations did for third rail back in the 1990's and on the face of it top contact third rail looks excessively dangerous but that's just not borne out by the facts on workforce and public injuries vs overhead line. So whilst its never going to be permitted for any new standalone installations there is a case to be made that extension to Uckfield is the only viable option to decarbonise that route. I wouldn't advocate that for Ashford to Hastings as its practical now to extend 25kV from Ashford same as Reading to Basingstoke. So that would leave North Downs Line as the only other route that infill with third rail should be allowed. The other option that could be contemplated is with battery powered trains is to remove con rail in platforms and use battery power in station vicinity as that's where most trespass events occur.
Tell that one to the "Smart Motorway" detractors, and journalists, writing about removing motorway hard shoulders to get more capacity on the cheap.
It's very easy. Because with bottom contact the collector shoes have to point upwards. They are of course live on both sides of the train, so when boarding there's the live shoes pointing up at you on the platform side from the bogies.
Would you care to evidence the bit in bold?
What it would have solved was that if a train failed to change over at City Thameslink it could be terminated in a platform with following trains able to route around it instead of having to turn everybody out and run into Smithfield sidings to reverse, with all the conflicting movements that entials. They could also have been used for normal terminating services instead of doing so at Blackfriars, and had they gone further and been built at Farringdon, passengers on the terminating services could then have fed directly onto Crossrail and the Met.
The upgrades for an AC system are also much wider in choice, considering the type of grid connection (DNO/NG), the voltage (33kV with SFC, 132kV, 275kV (not sure if a 275kV grid connection has been made, but you never know!), 400kV) and the traction current return (Return Conductor, RC + Booster Transformers, 'Classic Feeding' with Earth Wire and Return Screening Conductor, ±25kV Autotransformer/Auxiliary Feeding). Certainly with AT feeding, feeder stations can be spaced further apart (esp. if 400kV grid connections are used). SFCs are useful as they eliminate any phase imbalance in the DNO supply.
And it's still a risk for Steam working under 25KV today.
ECML has had several additional feeder stations added to it since it was first electrified although I acknowledge that to upgrade DC requires many more infeeds per mile in the form of new substations. However, converting OLE to an AT systems isn't without alot of line side infrastructure being needed as well additional feeder wires or miles of cabling that has been installed on ECML as well as being a lot more disruptive so in capital costs not a lot of difference. That said the availability of SFC's is a game changer as in my day (1980's AC electrifications) we were stuck with where the grid would allow a connection whereas on the DC side we just ran a 33kV cable to the local DNO 33kV substation.
Turns out that smart motorways are actually safer than dumb ones, of course, with some careful and thoughtful analysis of the data. That's too subtle and factual for many headline-writers though. There's a section about it (which starts at 08:05) in this episode of More or Less (BBC radio 4) — not aware of transcripts of these available anywhere online, unfortunately.
