The railway has long prided itself on its green credentials. And travelling by train continues to deliver significant environmental benefits compared to travelling by road or plane: lower carbon emissions, cleaner air, and less noise.

But will that advantage continue and, if not, what should we do?

Each year the Office of Rail and Road publishes statistics showing how rail is performing in terms of total carbon emissions and emissions per passenger km or tonne km. ORR has just published the stats for 2021/22 which you can find here.

The stats make for interesting reading. Pre-pandemic we saw a downward trend in carbon emissions per passenger km driven by things like higher passenger numbers, a reduction in the carbon intensity of electricity, and the wider use of bi-mode trains. But the impact of the pandemic was undeniably significant: the big drop in passengers resulted in emissions per passenger km going up over 300% in 2020/21, though overall rail emissions declined due to a reduction in passenger services.

ORR’s latest data shows that total traction diesel consumption increased by 9% in 2021/22 compared to the previous year, with electricity consumption rising by 1% in the same period. Though at face value this increase may appear bad, it reflects the steady recovery of passenger services - this position continues to improve as more passengers return to rail, but we’ve still got our work cut out to get back to pre-pandemic levels.

Conversely, the rail freight market has recovered strongly from the pandemic, with some markets now exceeding pre-pandemic levels. Although this means that overall freight’s carbon emissions have increased by 5% compared to 2020/21, rail freight is an environmentally friendly mode, producing 76% less CO2 per tonne than road, and moving more goods by rail is an important step in reaching net zero emissions.

In this year’s data, ORR introduced a new metric to measure rail’s carbon performance. This measurement calculates normalised rail emissions based on vehicle kilometre data, and has been calculated retrospectively back to 2011. In 2021/22 normalised passenger emissions declined by 7% on the previous year, with ORR reporting that total vehicle emissions per vehicle kilometre were the lowest on record. This reflects the continued introduction of new carbon efficient rolling stock, and the transition towards renewable sources of electricity used for rail traction.

The picture for rail freight is similarly positive with emissions per vehicle kilometre falling by 8% compared to 2020/21, also the lowest since the time began in 2011. Last year we saw several freight operators begin to use Hydrotreated Vegetable Oil (HVO) on some of their services, using HVO is reported to reduce carbon emissions by 90% compared to red diesel. However, soaring electricity costs led to a reduced use of electric traction for rail freight services.

But we can’t look at the ORR stats in isolation from how rail’s competitors are improving their carbon performance. I’ve certainly noticed a steady increase in the number of electric and hybrid cars on our roads which prompted me to look up the latest car sales figures. These show that one in five new cars is now either battery or plug-in hybrid. That upward trend will accelerate as battery costs come down and performance improves.

In aviation, progress is being made in developing electric planes initially for shorter distance regional journeys. Although it will take some time before we see the widespread use of this technology, it’s another sign that rail can’t be complacent.

So, how should the railway respond?

Back in 2018, the then Rail Minister Jo Johnson, set an ambition to remove all diesel-only trains from the network by 2040 and challenged the industry to provide a vision for how it will decarbonise. This resulted in some intensive cross-industry activity through the Rail Industry Decarbonisation Taskforce which then informed the Traction Decarbonisation Network Strategy and the DfT’s Transport Decarbonisation Plan. All of this work showed that it was feasible to decarbonise the railway and that we had the technologies to do it: primarily further electrification along with targeted use of battery and hydrogen powered trains. But what we didn’t have – and still don’t have – is a clear delivery plan and funding commitment. The case for investment is not helped by the current industrial turbulence on the railway which reduces funding and makes it harder to persuade decision makers.

We’re now waiting to see what emerges through the Whole Industry Strategic Plan (WISP) which is being developed by the Great British Railways Transition Team for the Department for Transport. The WISP will provide a long-term strategy to guide the development of the railway and how it can support government’s key policy objectives including around environmental sustainability. We hope the WISP will reinforce the importance of rapid action and investment to improve rail’s carbon credentials enabling it to play a central part in helping the UK economy to decarbonise.

Rail Partners’ recent prospectus “Working together for a better railway: a new public-private partnership” sets out our priorities for reform to attract customers back to rail, reduce the need for taxpayer support and develop a stronger public-private partnership focused on delivering for customers. Within this we call for a sustained government commitment to electrifying the railway as well as rolling out hydrogen and battery trains recognising that this will not only cut carbon but deliver wider benefits. As a large sector with predictable levels of energy demand, rail is well-placed to become an anchor tenant for alternative energy solutions which can help this emerging industry to invest and scale-up. Previous analysis estimated that these benefits could include the creation of around 6,000 jobs, economic benefits of £2.2bn associated with the roles needed to deliver a decarbonised railway and a further £2.2bn of value from health improvements from cleaner air. We also call for an ambitious target to treble rail freight volumes by 2050 and measures to encourage more people to choose rail through fares and marketing initiatives and discounts.

Whilst the railway must play its part in reducing carbon emissions, we also have to prepare for a changing climate. The UK can expect wetter winters, hotter and drier summers and more extreme weather events such as storms and floods. Indeed, the recent heatwaves we’ve experienced - which resulted in train services being cancelled and infrastructure struggling to cope – may well become the norm in the decades to come. So, ensuring our railway can adapt to our changing climate will be critical to delivering a reliable train service and attracting more customers to rail. This again will require sustained effort and investment.

Rail has the potential to become the backbone of a zero-carbon transport system. We have innovative suppliers and operators who have successfully developed and trialled novel low carbon technologies such as battery and hydrogen trains. But the missing piece of the jigsaw is a clear funded plan to invest in rail decarbonisation. If government can deliver this, it will stimulate operators and the supply chain to respond, and through a public-private partnership, a decarbonised railway can be achieved.