Passenger rail can reduce emissions, lower energy use and create a smaller environmental footprint

We cannot keep pumping CO2 and other greenhouse gases into the atmosphere. Passenger rail can reduce emissions.


Paul Callister & Laurie Winkless

2/14/20234 min read

The devastating flooding in Tāmaki Makaurau in late January and now the impact of Cyclone Gabrielle should provide a wakeup call that we cannot keep pumping CO2 and other greenhouse gases into the atmosphere.

Travel in fossil fuelled cars and planes represent a significant part of our gross domestic emissions in Aotearoa New Zealand. Recently-introduced targets to reduce transport emissions aim to change that. One goal, set out in the 2022 Emission Reduction Plan, is to reduce total projected kilometres travelled by the light fleet by 20 per cent by 2035. This is mainly to be achieved through improved urban form and by providing alternative travel options. While this plan focuses on travel within our largest cities, it is important to also cut travel between centres. Currently in New Zealand, these journeys overwhelmingly happen by road or air. As yet, we’ve seen far less focus on reducing the country’s aviation footprint. But Auckland’s Transport Emission Reduction Plan aims to reduce domestic aviation emissions by half by 2030.

This transition will be a very steep one, considering where we’re starting.

New Zealand stands out internationally in terms of car ownership and use, with one of the highest motor vehicle and car ownership rates per capita in the world. According to data from Waka Kotahi, there were almost 700,000 more vehicles on the road in 2022 than in 2017 – that’s a 14% increase in just five years.

New Zealand also ranks 6th in the world for overall per-capita aviation emissions, at 1 tonne CO2 per person, about 10 times the world average. It ranks 4th for per-capita domestic aviation emissions. on a per capita basis, New Zealanders emit seven times more than people living in the UK and nine times that of Germany. Part of the reason for the difference is their extensive rail networks and our lack of them.

The significant emission and energy benefits of using inter city and regional rail rather than driving or flying are well established. Steel-wheels upon steel-rails provides low friction and therefore low rolling resistance, resulting in reduced energy usage. A fully electrified passenger rail service uses a fraction of the energy needed to drive or fly people over the same distance, while also creating a fraction of the emissions. In relation to freight, the Value of Rail study published in 2016 showed that even diesel-powered rail freight services offer 70 percent fewer emissions compared to heavy road freight transport. Railways also use far less space than roading networks.

Yet, pushing back on this view are those who see rail as old technology. Why invest in rail when we are told electric planes, or planes fuelled by biofuel or hydrogen, are just over the horizon? Perhaps the answer is more widespread adoption of electric cars?

Various studies show that such ‘zero emission’ planes are not yet rolling off production lines. In fact, aside from small demonstrator models, electric passenger planes exist only on the drawing boards of designers. Larger planes suitable for regional connections, and those powered by hydrogen are even further away. The latter comes with the complexities of storing and using hydrogen in large volumes. And while ‘sustainable aviation fuels’ are being used in a very small number of flights, scaling up production of these fuels is proving to be a major challenge. Biofuels not sourced from true waste products, such as forestry offcuts, are especially problematic. Unfortunately, they also currently represent the majority of today's commercially-available biofuels; produced from potential food crops, such as palm oil, or ‘used cooking oil’.

In addition, today’s train technology has advanced far beyond the ‘old fashioned’ ideas held by some critics. In countless countries across the world, rail networks have been powered by electricity for decades – initially via overhead wires, many are now using batteries. Since 2017, the electricity that powers all Dutch trains has been generated from wind power. While the use of hydrogen is subject to much debate, hydrogen trains are already in operation, with new versions in development in China.

Since 2021, KiwiRail has been developing high-level feasibility cases for electrifying the remaining segments of the North Island Main Trunk and East Coast Main Trunk. The vast majority of the North Island rail freight traverses the two mainline routes. These routes provide for freight connectivity between the largest North Island cities of Auckland, Hamilton, Tauranga and Wellington and can easily be leveraged for passenger rail operation.

There are significant reasons to support such mode shift in New Zealand. For example, two-thirds of GenZers who say that they “think about their environmental footprint” would consider taking a train instead of a plane to travel. And we’ve seen through submissions to our campaign that tens of thousands of New Zealanders support rail, and see it as an attractive alternative to driving and flying. But without a mix of incentives and disincentives that work for our population, such a shift may not happen. The most effective incentives are often very simple – as our fellow campaigner Suraya Sidhu Singh wrote in The Spinoff, “frequency is one of the biggest drivers of public transport uptake, especially in winning over those who currently drive.”

We cannot use 1990 or even 2000 thinking when considering the role of passenger rail in Aotearoa. Decisions made back then should not be determining how we will live in 2030, 2040 or 2050.

Organisations also have a significant role to play in achieving the required emission reductions. Businesses, including universities, increasingly have to account for their transport emissions. Following the declaration of a climate emergency in November 2020, the government released the cabinet paper Leading the way: Establishing a Carbon Neutral Government Programme (CNGP). The paper states that the government “must show leadership to reduce its own emissions, in order to demonstrate what is possible to other sectors in the New Zealand economy.” The emissions footprints of the main government agencies are due to be published soon. Based on earlier data, it is expected that domestic flying will be a major contributor, and to meet the goals of CNGP, will need to be reduced. The general manager for sustainability for Vector, Prageeth Jayathissa, has ‘walked the talk’ by demonstrating the climate benefits of using the train between Auckland and Wellington.

Transport mode shift similarly requires a mode shift in imagination and vision by the tourist industry and how we ourselves holiday. Kirsty Wild has written how we need to change how work is organised so we can move away from short breaks that often involve flying. And to reduce emissions, we need to holiday more locally.

Living a "1.5 °C" lifestyle – about 2.5 tonnes CO2 a year until 2030 – is challenging. A key element to achieving is adopting low-emission, high energy-efficiency approaches to domestic mobility. As we say, The Future is Rail.