KiwiRail to end electric freight haulage

[009 micro modeller]

Dual-voltage locos generally have different pantographs for each system. Sometimes, as with tram-trains, the same pan can be used. This is possibly because the speed and/or the current is lower.

Isn’t there potential for the high pantograph to be damaged by (or cause damage to) the low wire?

[PhilJ W]

Isn’t there potential for the high pantograph to be damaged by (or cause damage to) the low wire?

It can and does happen. When Eurostar operated into Waterloo on the third rail system pantographs were left up a couple of times and damaged as a result.

[Edwin_m]

Isn’t there potential for the high pantograph to be damaged by (or cause damage to) the low wire?

The wires on different overhead systems are usually around the same height (and may vary in height anyway).  The need for multiple pantographs is probably one or more of:

• High voltage needs larger electrical clearances but lower voltage means high current which may mean a heavier pantograph
• Different dynamic characteristics to be compatible with different types of overhead line
• Different pantograph head widths (I seem to recall one of Germany/Switzerland/Austria is non-standard from the other two in this respect despite running the same voltage and frequency)
• Risk of damage to equipment if connected to the wrong voltage. 

[Steamysandy]

Good to see de-electrification cancelled - I’ve always seen it as a backwards step apart from in a few specific situations. I was under the impression that it was the ECML beyond Newcastle Railtrack was going to de-wire, supposedly because a lot of trains north of there also went north of Edinburgh and would have to be diesel anyway. I presume for dual voltage where both are from overhead lines that a neutral section is involved for changeover, but what happens if the pantograph type/wire height is different as well as the voltage?

I believe initially it wasn't intended to electrify Newcastle - Edinburgh but to use the class 50s for this section.Trials carried out at Newcastle showed that there were going to be problems with loco changes and the idea was dropped.

Subsequently it was realised that Edinburgh to Carstairs was no great mileage and it was added to the programme but was completed first,before the Newcastle line was done by several months.I was at a meeting (Through my work at BT!!

)when the Carstairs plan was revealed by a BR manager.

Subsequently the North Berwick line was added.

And this in turn led to the current wiring set ups between Edinburgh and Glasgow

[Noggin2018]

Very good news. The new Government appears to be very rail-friendly, and this decision should buy enough time for the pieces to fall into place to enable further rail electrification in New Zealand. With the extension of the electrification at the Auckland end, the gap between the Auckland and central 25kV systems comes down to something like 80km, which should improve the business case no end, and a third main line should create paths for freight and medium distance express passenger services.

 

One problem is that it's unlikely that the EF's could run into Auckland - even if the power supply can cope with them, I suspect that the electro-magnetic interference might be a bit too much for the signalling to take, and the locos would possibly need ETCS signalling kit installing too. So that probably means power-supply upgrades, expensive signalling upgrades and/or more likely, replacement of the EF's with something more up to date and better mannered.

 

As Edwin_m and others have said, multi-voltage locos (and EMU's) with 25kV and 1500V DC capability are very much an 'off the shelf' product these days, including with 'last mile' diesel engines, and increasingly with 'last-mile' batteries. Whilst the track and loading gauge probably rule out one of Siemens standard products, it's the sort of thing that Stadler do very well, and of course I'm sure the Chinese chaps that built the DL's would be only too happy to quote.

 

Modern kit can sense line voltages and deal with it automatically (or have changeover prompted by a track-side ballise). Pantographs can also vary the amount of upwards pressure they exert to cope with lines strung at different tensions, so in most cases the same pantograph can be used on multiple systems, with the exceptions that Edwin suggests. For example, IIRC, French high-speed lines have wires at a fixed height, and so the pantograph is essentially fixed in position when the unit is on that system.

 

The other issue is that much of the freight out of Auckland actually goes to the port of Tauranga. That's something like 100km east of Hamilton, so with a bit of Government support, there might be quite a good business case for electrification.

 

A further advantage of electrification would be that medium distance rail services could be run from Auckland's (underground) Britomart station to Hamilton and Tauranga.

[PhilJ W]

The Liverpool Street lines used to run on dual voltage 25 KV on the 'country' lines and 6.5 KV towards London. IIRC the changover took place near Chadwell Heath. It was very noticable on the 305 units, if you rode in the carriage with the guard compartment, a loud clunk followed by a vibrating sound.

[John M]

Very good news. The new Government appears to be very rail-friendly, and this decision should buy enough time for the pieces to fall into place to enable further rail electrification in New Zealand. With the extension of the electrification at the Auckland end, the gap between the Auckland and central 25kV systems comes down to something like 80km, which should improve the business case no end, and a third main line should create paths for freight and medium distance express passenger services.

 

 

A further advantage of electrification would be that medium distance rail services could be run from Auckland's (underground) Britomart station to Hamilton and Tauranga.

It will be interesting to see what happens after the next General Election. The principal opposition party who have a reasonable prospect of being elected in 2020 are heavily committed to roading. They oppose the proposed Auckland Light Rail Scheme and are on the record that they will cancel the contracts and dismantle any works carried out on the project when elected.

 

While the current coalition Government is pro rail, there has been little political support for reinstating/developing intercity passenger services, possibly because rail in New Zealand has long lost its relevance as a means of long distance passenger travel, a combination of low population density, distance between centers that make air more attractive than road or rail and the constraints of a narrow gauge railway system through challenging country.

 

There were attempts to re-introduce a Hamilton-Auckland commuter service approx 10-15 years ago, but the project was scrapped and the road to Auckland upgraded to motorway standards (by 2020) following of a change of government. The proposal was largely based on a daily commuter service to Newmarket (Auckland) using one of the 170 seat Silver Fern railcars. Current proposals are based on a Newmarket-Hamilton (Frankton) service. Operating a passenger service over the East Coast Main Trunk into Hamilton Central Station or Tauranga would be difficult as the single line through Hamilton CBD carries very heavy freight traffic and its doubtful that it is economically or technically feasible to double the line  from Frankton to the CBD as much of the route is built over in single track tunnel.

 

The central portion of the NIMT was electrified primarily to speed up journey time of long distance freight services over the most challenging section of the line as the railway evolved into a long distance express and bulk freight carrier as rail lost its legal protection from road competition. 

 

Its difficult to see an operational case for extending the electrification through to Auckland and Wellington without electrifying the majority of lines in the North Island.

 

Both Hamilton and Palmerston North the two ends of the electrified section are important junctions and major traffic centers with heavier traffic (density and tonnage) on the (very long) branches off the main trunk to the Bay of Plenty, Improving alignment and easing grades on both the NIMT and regional lines would at this stage would be a better alternative to extending electrification through to Auckland and Wellington, both in speeding up journey time to improve rails competitiveness with road and possibly in managing emissions. Retaining the relatively new DL fleet until they require replacement may result in lower emissions than, constructing a new fleet of electric locos and the works in connection with electrifying the route, Kiwirail use a combination of bio diesel and engine management systems to reduce emissions/fuel usage.