I think you would dual St Denys to Southampton (with all the complications Bald Rick mentions) for Southern; SW would need dual voltage units anyway, though you might retain 3rd rail in Basingstoke station area too.
I believe the intent is to have a first stage is to do Basingstoke-Salisbury-Romsey-Redbridge, so the dual systems would be Basingstoke-Worting Jn and Redbridge-Millbrook only. In an ideal world, you'd then do Southampton Central - Weymouth, before moving on to the route via Winchester. How it actually happens is a different matter entirely.
Are you saying you think electrification should be only for freight? There's plenty of electrification schemes that are for passenger trains only, let alone those with a residual freight impact.
No I am not saying electrification should only be for freight, I am saying the main justification in this case is for freight from Southampton to Reading and beyond.
Ah, with you now. Because your post was standalone I thought you were making a general comment, rather than talking specifically about Basingstoke-Southampton.
New 3rd rail has been discussed many times here and elsewhere, most importantly by the railway authorities who have said that there will be no more new routes introduced with it, so it is out of the question. Also, in rural areas where there are less overbridges per mile than in urban areas, the higher cost of clearing a route for OLE can be minimal. Ensuring a high current feed to longer stretches of DC electrified track* requires a much more complex supply infrastructure than with 25kV where the whole Basingstoke/Salisbury/Romsey/Southampton route might only need a single grid feed for 25kV OLE, and there are three high voltage lines crossing or very near to the route:
Not true because even if there was no deliberate earthing point for the supply, (e.g. the LU lines are -1/3 +2/3 nominal voltage), a fully floating supply would establish a voltage relationship with true local earth by virtue of leakage currents well below fault levels. The current available would be well above human fatal levels.
So let's see, there's dirty maybe wet insulators every few metres, leaves against the foot of conductor rails, locos with a layer of brake dust on the shoe beam etc. ... You are welcome to shake hands with 375V that you didn't know was there. It might have as little as 1A potential current, out of the (say) 3000A load at any time a train is in the section, (that's about 10x the almost gauranteed lethal current needed, 100-200mA). Once you get to that sort of current you have little chance of avoiding life-changing (or life-ending) injury.
Brussels-Midi has some staggeringly long headspans. Looks like a full suspension bridge from outside the station.
Merseyrail is very much a heavy metro; operationally, there would be little benefit to switching over.
Except where the lines surface. Switching over to OLE would remove interoperability issues with main line services, e.g. Hunts Cross. One day (hopefully soon) the CLC line between South Parkway and Castlefields via Warrington Central will get electrified in order to meet the deamnd for slow and fast services. If the Merseyrail services switched over to 25kV ac soon after emerging from the tunnel (suggest St Michaels station), there would be no need for segregation of DC & ac at South Parkway junction, and the Allerton headshunt could be realingned to provide access for ac stock on the CLC line.
It would operationally simpler to have OLE energised at 750v DC so the 777 can switch from shoe to pantograph, the same voltage used successfully by tram systems in Britain, Sheffield have dual voltage tram set with TOPS numbers class 399 that was for a good reason to be able to run on BR lines into the city street, it's a complicated tram set to go from 750v DC to 25kv AC.
Complicated but achievable. And Marseyrail has more space to put the electrical equipment under the train than a tram.
no it wouldn't, 769s are dual voltage + train borne power.
The suggestion for 25kv was for Lime street-warrington Central-Manchester trains to be electrified, and Mersey rail to share the section East of Hunts Cross. So 750v wouldn't be suitable.
My point was that the 777 number is perfectly suitable for a class capable of 25kv operation. I said nothing about 769s being a viable stock option for merseyrail.
