Ask Phoebe: Dual-voltage systems would ensure compatibility of electric rail services

Photo / Herald on Sunday

Q. At present electric trains operate on the main trunk line between Hamilton and Palmerston North. There are also electric suburban train services in the Wellington region. My understanding is that these two systems are not compatible, because they employ different electric systems. One service is on AC power and the other on DC power.

I wonder how the new Auckland suburban system will fit into this? Will it be possible, in the distant future, to extend the Auckland suburban services to Hamilton and Whangarei? Will it be possible to run electric trains between Auckland and Wellington without changing the engine twice? Kees Slabber, Auckland.

A. Your understanding of the electric systems is correct. The Wellington traction system is 1500V DC and the North Island Main Trunk and Auckland system are, or will be, 25kV AC.

The two systems are not directly compatible, says OnTrack, which owns and manages the rail network on behalf of the Government. However, it is possible to build trains with dual voltage systems to drive one set of electric motors, and this is currently (couldn't resist the joke) in use in various places in Europe.

The acquisition process for Auckland's electric trains has just begun, and the configuration of the new trains has yet to be established, but I imagine that all possibilities will be taken into account. And yes, it will be possible to extend the Auckland electrification system to Whangarei and Hamilton in the future.

Q. Are there any plans to build a railway station beside the Southgate shopping centre on Walters Rd in Takanini? The new residential suburb of Addison has opened up in this area and traffic congestion is horrific in peak hours, yet despite there being a railway running right through the area there is no station. The nearest stations are quite some distance away. Kathryn Arnold, Takanini.

A. Sorry. The answer is no.

Q. Some new railway sidings are being built parallel to Railside Ave in Henderson. Do you know what they are for? Jonty Victor, Western heights.

A. It is a stabling facility for trains. Because of the double-tracking of the western rail line, there are now more train services than previously. To save returning trains to a central point when they are empty, KiwiRail has built sidings, or stables, where the trains can stay overnight, ready for the morning onslaught.

The Henderson facility is due to be commissioned this month. The other distributed stabling projects are at Pukekohe and Papakura.

Q. My wife and I wonder what the building is that's being constructed over the new underground railway station at New Lynn. Wayne Nicholls, West Auckland.

This is the New Lynn rail and bus interchange, a very grand thing indeed. There will be island platforms within the trench to service the railway lines, between Memorial Drive and Hetana St.

Access from the platforms to the interchange above will be via stairs, lift or escalators. Inside the interchange will be a waiting area, bike racks and the like, and also access to the bus platforms on Totara Ave and Clark St. The new station is scheduled to be completed in September.