
By Rebecca Hollett, KiwiRail Client Leader and Principal Infrastructure Advisor, Peter Algie, Associate Integrated Transport and Mobility and Guo Qi Peh, Lead Consultant, Transport, Aurecon.
Freight rail can be an enabler for decarbonisation and New Zealand’s transition to lower carbon emissions. Benefits of shifting freight onto rail include improved safety and reliability and less pollution, with estimates showing one short haul freight train can remove up to 40 trucks and trailers from the road – equivalent to a 66 to 70 per cent reduction in carbon emissions. But, to achieve a successful transition, the future rail network must be resilient, reliable and efficient.
Aurecon has released a thought piece proposing three significant changes to New Zealand’s rail freight network to support economic growth and decarbonisation for a lower emissions future. These are:
- Developing a national freight strategy
- Removing diesel traction
- Linking track and enabling infrastructure.
This article focuses on the importance of a national freight strategy.
Challenges and opportunities in decarbonising freight rail
While there are many compelling reasons for transitioning to a decarbonised freight rail system in New Zealand, there are inherent challenges:
- Electrification is currently the most effective option to reduce emissions for freight rail along urban routes and the ‘whole-of-life’ costs of new electric locomotives are also decreasing in comparison to new diesel locomotives. However, on rural lines, this becomes much more expensive and often not feasible. This is particularly relevant for the South Island as it currently has no electrification of either the freight or passenger rail network.
- As operators need to reduce emissions from freight transport, as well as reducing the emissions intensity of transport fuel, alternative fuels may be more economically and viable compared with electrification. While lower carbon fuel alternatives are becoming increasingly available to replace diesel, with increasing investment by major manufacturers, future fuel solutions are hindered by the country’s steep terrain, high capital and/or operational costs and are not yet available at-scale.
- To be commercially competitive, rail freight infrastructure must effectively link freight origins and destinations with hubs and ports, supported by efficient intermodal interfaces.
Given these challenges, a series of initiatives are required to achieve freight rail decarbonisation, underpinned by a national freight strategy, removing diesel traction, linking track and enabling infrastructure (figure 1).
Developing a national freight strategy
A national freight strategy is needed, to realise the benefits freight rail transport can offer in replacing, or at least reducing, carbon-intense road freight. Te Manatū Waka Ministry of Transport is currently developing a national freight strategy. The issues paper, released for comment, presents five key factors: decarbonisation, resilience, productivity, innovation and well-being.
It’s important that a national freight strategy provides the mechanism to enable action and ambition from governments, at all levels, industries and businesses, to lift freight system resilience and reliability.
Looking ahead, coordinated and well-planned government and industry action across the freight rail sector over the next 20 years and beyond will contribute to a strong and prosperous New Zealand.
Benefits of a national freight strategy
The key outcomes achieved would be:
- Improving freight rail links to freight gateways
- Facilitating investment in rail assets and enabling infrastructure
- Removing barriers to moving freight seamlessly along supply chains
- Future-focused freight regulation (productivity, safety, security and sustainability)
- Enabling a digital future with a national approach to data consistency.
Freight terminals and intermodal precincts maintain a central position in supply chains as they enable a hub-and-spoke model where freight travels long distances by rail and its last-mile delivery is by road. If freight rail is highly used, two-way running (i.e. minimised empty running) is achieved, thereby reducing its carbon per volume / tonne of freight moved.
These terminals and precincts, such as the regional freight hub proposed by KiwiRail at Palmerston North, are essential building blocks for the overall efficiency of supply chains, increased rail use, and decreased long haul truck movements and carbon emissions. Securing the role and location of New Zealand’s major ports will be key to enabling the investment necessary to implement a successful national freight strategy.
Links to decarbonisation
Network infrastructure upgrades that enable accelerated and increased levels of service will support growth opportunities and regional initiatives.
This becomes particularly important on rural lines that support national economic development by enabling movement of commodities such as wood, food and dairy, to major cities and to seaports for export, such as the North Island Ports of Auckland and Tauranga, and Lyttleton Port in the South Island. Investment in these linkages increases throughput of freight, while improving the resilience and sustainability of the infrastructure that connects to it, such as ports and intermodal precincts.
Not only does moving freight by rail produce fewer carbon emissions than road freight, it also lowers roading costs such as new construction or ongoing maintenance, reduces congestion and creates safer roads by taking freight off the roading network. A number of linked track and enabling infrastructure factors are critical to decarbonising the journey of freight (figure 2).
Freight rail, the next track
For rail to live up to its role as the freight backbone of New Zealand, it has to act quickly and decisively to reduce carbon emissions and be a force for change in the country’s decarbonisation journey.
To read Aurecon’s full paper, click here.

