AWARDS FINALIST: KiwiRail – Decarbonising KiwiRail’s shunt fleet for a sustainable future
KiwiRail has procured 51 electric and hybrid shunting assets during the past eight years as part of a fleet modernisation programme that will reduce operating costs and emissions.
By the time the programme is completed in 2029, almost two-thirds of the shunting fleet will be fully electric or hybrid.
That is expected to avoid about 776 tonnes of carbon dioxide-equivalent emissions annually and will reduce operating costs by more than 40 per cent over the assets' 25-to-35-year operating lives.
The project is a finalist in the large energy user category of this year's Energy Excellence Awards.
Shunting involves moving wagons, carriages and locomotives short distances within rail facilities, and is a core part of rail operations.
KiwiRail says the programme replaces ageing diesel-powered shunt locomotives and tractors with electric and hybrid alternatives across rail yards and workshops.
The procurement includes 27 fully electric shunt vehicles and 24 hybrid battery-diesel shunt locomotives.
Fleet
The electric fleet comprises 16 light shunt vehicles capable of moving between 110 and 300 tonnes, and 11 heavy shunt vehicles capable of moving up to 2000 tonnes.
The hybrid DSH-class locomotives can move up to 2500 tonnes and operate on the mainline at speeds of up to 80 kilometres an hour.
KiwiRail says a key aspect of the procurement process was the decision to assess its operational requirements and introduce smaller electric vehicles where appropriate, rather than simply replacing the existing diesel assets on a like-for-like basis.
That has allowed lighter shunting tasks to be completed with lower energy demand units, while reserving higher-capacity assets for heavier movements.
An important component of the programme has been the deployment of battery-powered shunt vehicles that can operate on both road and rail.
KiwiRail says their compact design and remote-control capability enable shunting operations in constrained yard and workshop environments while reducing reliance on larger diesel locomotives.
Implementation has progressed through a long-term procurement programme and has required operational and cultural changes as staff adopted fully remote-controlled electric vehicles in place of traditional diesel shunting equipment, the company says.
Other benefits
As well as reducing fuel costs, KiwiRail says the change will reduce maintenance complexity and improve reliability.
It will also provide operational safety benefits, including the use of remote-control systems, continuous braking, automatic couplers, and the use of deadman switches.
KiwiRail says those features reduce reliance on manual coupling, chocking and other higher-risk shunting activities.
The company says staff are also benefiting from reduced particulate emissions and noise from rail operations, particularly within workshops and urban rail environments.
KiwiRail says the experience gained through the shunting fleet programme is informing a separate business case examining train electrification in the Auckland-Hamilton-Tauranga freight corridor.
The annual Energy Excellence Awards will be held in Wellington on 19 August. The Large Energy User Initiative of the Year award is sponsored by Energy Efficiency and Conservation Authority.