third rail locomotives

[popeter45]

with how effectly all freight that covers the southen region being diesel hauled is it time to think about a modern replacement for the 73's?
would some kind of battery bi/tri mode work that runs on third rail but with a battery to act as a buffer for power draw needed would outstrip what the rail can provide?, basicly a 92 but with batteries as well so it isnt confined to specific routes?, would also allow it to work in unelectrifed sidings and last mile mode

 

[30907]

with how effectly all freight that covers the southen region being diesel hauled is it time to think about a modern replacement for the 73's?
would some kind of battery bi/tri mode work that runs on third rail but with a battery to act as a buffer for power draw needed would outstrip what the rail can provide?, basicly a 92 but with batteries as well so it isnt confined to specific routes?, would also allow it to work in unelectrifed sidings and last mile mode

Interesting. Is there a significant volume of 3rd-rail-only freight, because dsughter-of-ED would be little use off the juice?

 

[popeter45]

Interesting. Is there a significant volume of 3rd-rail-only freight, because dsughter-of-ED would be little use off the juice?

not sure of pure 3rd rail but thats why i suggest tri mode as in battery, 3rd rail and AC so stuff like the stone trains on the NLL can move from class 66's

 

[zwk500]

Interesting. Is there a significant volume of 3rd-rail-only freight, because dsughter-of-ED would be little use off the juice?

In short, no. You'd need last-mile capability anyway as new 3rd rail would be a no-no in yards and overhead line makes it hard to load wagons from the top.

You get a small amount of aggregates movements that start and end in third rail land but they often have to make a brief excursion off the juice in West London to avoid running round. However most freight in third rail land is either Aggregates heading to London or containers heading to the Midlands. There are a few smaller flows about (fuel to Heathrow being one, some HS1 stuff as well) but by and large it's stone or boxes.

not sure of pure 3rd rail but thats why i suggest tri mode as in battery, 3rd rail and AC so stuff like the stone trains on the NLL can move from class 66's

AIUI The class 99 looked at the options and was told they could have only 3 of the 4 modes (AC, DC, Battery and Diesel) so they plumped to leave DC shoes off and take Battery and Diesel instead. DC power also has the risk of gapping, which is a pain and 3rd rail shoes are liable to get torn off if people leave things too close to the 6ft.

 

[popeter45]

AIUI The class 99 looked at the options and was told they could have only 3 of the 4 modes (AC, DC, Battery and Diesel) so they plumped to leave DC shoes off and take Battery and Diesel instead. DC power also has the risk of gapping, which is a pain and 3rd rail shoes are liable to get torn off if people leave things too close to the 6ft.

afaik 99 is AC + Diesel only, no battery unlike the 93's
also on the 93's whats the planned battery range?, if plan is full removal of Diesel you will 100% need the ability to recharge the batteries en-route

 

[43096]

afaik 99 is AC + Diesel only, no battery unlike the 93's
also on the 93's whats the planned battery range?, if plan is full removal of Diesel you will 100% need the ability to recharge the batteries en-route

Rather than dealing with various niche situations, like third rail freight and branch line battery trains, there really needs to be a concentration of effort on the biggest areas. In other words, get the wires up on the more heavily used routes and stop fannying around being distracted by edge cases.

 

[MarkyT]

DC power also has the risk of gapping, which is a pain and 3rd rail shoes are liable to get torn off if people leave things too close to the 6ft.

Class 71s had a flywheel booster storage system to power through gaps that short self-contained vehicles like locos are prone to, and to make other short off-grid excursions in sidings for example. Having batteries on board would also help with gapping and could assist with power management by reducing the current draw from the 3rd rail during brief surges in demand without affecting performance. Mk1 MLVs (motor luggage vans) had batteries onboard and were effectively low-powered (~500HP) locomotives that could haul short rakes of unpowered vehicles, as well as work in multiple with most 3rd rail EMUs of the era.

 

[popeter45]

Rather than dealing with various niche situations, like third rail freight and branch line battery trains, there really needs to be a concentration of effort on the biggest areas. In other words, get the wires up on the more heavily used routes and stop fannying around being distracted by edge cases.

the fact they didnt even do that for Eurostar and instead developed retractabled third rail shoes shows just how expensive and complex that would be

 

[Fawkes Cat]

with how effectly all freight that covers the southen region being diesel hauled is it time to think about a modern replacement for the 73's?
would some kind of battery bi/tri mode work that runs on third rail but with a battery to act as a buffer for power draw needed would outstrip what the rail can provide?, basicly a 92 but with batteries as well so it isnt confined to specific routes?, would also allow it to work in unelectrifed sidings and last mile mode

Are there freight flows (current or realistically prospective) that are entirely (or with the batteries, almost entirely) within the third rail network?

Sorry - please ignore. Written a while back but only just pressed 'send'

 

[zwk500]

the fact they didnt even do that for Eurostar and instead developed retractabled third rail shoes shows just how expensive and complex that would be

Eurostar was 400m long so didn't have to worry about gapping, and @43096 is proposing wiring lines like Nuneaton-Felixstowe not converting the 3rd rail network to OLE.

The runs on the third rail network are not that long, and could be covered by a clean AC/battery unit if you devoted more space to the batteries. There may need to be a shore charger at freight terminals but they could be trickle charged from the local distribution network.

Are there freight flows (current or realistically prospective) that are entirely (or with the batteries, almost entirely) within the third rail network?

There are a few aggregates trip workings, mainly from the big yards at Eastleigh, Tonbridge and Hoo to the terminals in Sussex. But the vast majority of 3rd rail freight leaves the region.

 

[61653 HTAFC]

You get a small amount of aggregates movements that start and end in third rail land but they often have to make a brief excursion off the juice in West London to avoid running round. However most freight in third rail land is either Aggregates heading to London or containers heading to the Midlands. There are a few smaller flows about (fuel to Heathrow being one, some HS1 stuff as well) but by and large it's stone or boxes.

Imagine the size and weight of batteries you'd need to get any sort of range on the heavy stone trains though.

 

[zwk500]

Imagine the size and weight of batteries you'd need to get any sort of range on the heavy stone trains though.

No worse than a diesel engine, I suspect. Good for traction!

 

[popeter45]

how viable would a battery wagon be for such a situation?, could you get connections than can handle the load and are safe for coupouling?

 

[zwk500]

how viable would a battery wagon be for such a situation?, could you get connections than can handle the load and are safe for coupouling?

If it was permanently coupled, yes. However Battery wagons are probably better as a specialist solution in yards for Locos that are more 'Electric with emergency batteries' than full Bi-mode. Double-heading would seem to be a more sensible solution, if you can get a sufficiently sophisticated multi-working control to manage power and range appropriately.

Don't forget that battery locos would almost certainly have regen braking so range would be 'topped up' en route.