At the end of 2020, with mounting pressure to affect change that delivers its carbon reduction goal, the Labour Government declared a climate emergency for Aotearoa. The transport industry’s response to this emergency is pivotal and rail is no exception.

One of the most significant changes the rail industry can make is to remove diesel traction. However, currently only 14% of the network in Aotearoa is capable of running an electric train.

In my paper, Delivering rail decarbonisation to New Zealand, I investigate the wider challenges, efficiencies and opportunities that are involved in making the transition.

Fundamentally, overhead electrification is the most effective option to reduce emissions for high-speed, freight and long-distance routes. However, it’s expensive and due to its impact on overhead structures - along with other rail systems - isn’t feasible for deployment on all routes in Aotearoa.

Of course, cost is only one consideration. The feasibility of the solution and environmental considerations are equally important and given the long-term nature of rail infrastructure decisions, understanding life-cycle costs will be a critical part of any future business case.

At this stage we can only focus on the North Island. The South Island has no mainline electrification whatsoever and, due to relatively low utilisation of long and isolated stretches of rail line, electrification isn’t practicable in the foreseeable future.

In my opinion, a decision to complete the electrification of the North Island Main Trunk (NIMT) and metro commuter lines would create rolling stock buying power, scale and procurement simplification. This would also generate a horizontal infrastructure offering of a scale to prompt investment in resources. This investment in people and machines would reduce the average per kilometre cost of electrification over the medium to long term.

This established workforce and machinery could then be positioned to take on further electrification beyond the NIMT with the benefit of significant insights and efficiencies.

One of the biggest challenges is that we don’t have a long-term pipeline of agreed work that would justify the development of specialist human and capital resources, and could focus on expanding electrification and driving down the per kilometre cost. Current projects are piecemeal, meaning specific practices and plant that is imported or developed quickly disperses at the end of each small project.

A better approach would be to have these resources contribute to a locked-in reduction in the cost and timeframes per kilometre of new electrification.

The policies are sound, the targets are set, and the political commitment is real and sustained to deliver a decarbonised transport network. Now we need the bold intentions, targets, and policies from central government to be backed up with meaningful, targeted funding for low and zero carbon solutions.