Rail

Countries and regions making notable progress in this sector include: 

• China's railway network reached 155 000 km by the end of 2022, of which 42 000 km are high-speed railways.¹ The largest high-speed rail system in the world has grown 100 times in the past 20 years and is expected to further expand to 50 000 km by 2025, improving access to mobility, enabling modal shift and reducing oil demand. 
• Japan's Hitachi and Italy's Trenitalia together introduced the FrecciaRossa 1000 high-speed train in Italy in 2015, and it is now also operating in France and Spain, expanding the European railway market and improving rail competitiveness. In 2022 the partnership presented a new high-speed hybrid train that can switch between battery, electric or diesel and can function in both electrified and non-electrified lines, further modernising the European rolling stock.  
• India is investing in road-to-rail shift and is rapidly moving towards its target of 100% rail track electrification by 2024, with the share of electrified track increasing from 45% in 2015 to 80% in 2022.  
• Ethiopia-Djibouti's 753 km rail line, powered by hydro-generated electricity, started operating in 2016 and is the first modern electrified railway in East Africa, bringing economic growth and taking tonne-kilometres off the road.  

¹Considering high-speed train’s commercial speed of 200 km/h and above. For IEA modelling purposes, a high-speed train is considered to have a commercial speed of 250 km/h and above. 

Electric rail, which accounts for over 85% of passenger rail activity and 55% of freight movements, does not emit any direct CO₂ emissions. Urban rail networks such as metro and light rail tend to have significantly lower emissions than other motorised urban transport modes, especially private cars, as they are powered by electricity, have lower friction losses, and exploit high occupancy rates. On a well-to-wheels basis, rail emissions per passenger kilometre average around one-fifth of those of air travel. Emissions from electrified passenger rail are even lower when powered by renewables or nuclear power. In general, rail transports around 7% of global passenger-km and 6% of tonne-km but accounts for only around 1% of transport emissions.  

Expanding rail networks and their use will be important for achieving emission reductions to get on track with the NZE Scenario. European players are planning important investments in rail transport to make it more appealing to travellers, especially as an alternative to short-haul flights. 

The overall final energy mix of rail is currently split between diesel and electricity, with diesel consumption being 53% of total final energy demand compared to 45% of electricity share in 2022 (and biodiesel accounting for the remaining 1%). By 2030 in the NZE Scenario, electricity makes up 60% of total energy demand, with diesel still accounting for over a third, and biodiesel for most of the remaining share, with very minimal penetration of hydrogen.  

Diesel, in particular, plays a much more prominent role in freight rail, accounting for 75% of its total energy consumption worldwide in 2022. Continuous progress on freight electrification sees this share dropping to around 55% by 2030 in the NZE Scenario. 

Rail is also being more frequently explored as a solution that can provide synergies across the transport and energy sectors, which can bring numerous benefits, especially in developing economies: 

• energy access – bringing clean energy access to wider geographies through rail network projects 
• energy security - using rail infrastructure to regulate electricity demand and manage energy storage 
• sustainability – using electric rail as a baseload demand guarantee to support the business case for renewable energy investments. Additionally, if the area is particularly suitable for clean energy generation, this can make the case for electrification of the rail infrastructure bringing green financing to the transport sector. 
  

The world’s operating metro systems cover more than 21 000 km. Over one-third of these were put into operation between 2017 and 2021, and 80% of these new metro lines were built in Chinese cities. The picture for light rail, which has lower capacities and speeds, is similar, if less stark: over 10% of operating lines were put in place in the same five years, with just under half of them in China. The resulting efficiency of urban mobility in China results in far lower per-capita transport emissions than in cities of the developed world that are not served by metro, and can help China realise its net zero CO2 emission commitments.  

More than 20 countries have developed high-speed rail networks, totalling almost 60 000 km of line. China already has about 70% of the world’s line length and has long-term plans to operate nearly 65 000 km. Morocco has had great success with high-speed rail, opening the first high-speed rail system in Africa in 2018, and – in 2022 – starting to power its high-speed trains with renewable energy. Under the NZE Scenario, activity levels in high-speed rail need to increase by 75% in 2030. 

Night rail services offer additional traffic at a lower marginal cost, making infrastructure investments more profitable. Renewed interest has led to an expansion of night rail connections, demonstrating that this form of travel is gaining appeal and becoming a valid competitor with aviation for short- and medium-distance trips. Europe has seen the opening of several new night lines over the past couple of years, including overnight trains between Paris and Vienna, Amsterdam and Zurich, and Brussels and Prague, each with a number of intermediate stops. Night trains have continued to be an established practice after the Covid-19 pandemic in Eastern Europe, Asia and to a lesser degree in North America. 

Demonstration projects in the Netherlands, Canada and Japan aim to test the viability of hydrogen as an alternative to diesel rail lines with low utilisation and as a low-carbon fuel for rail in certain operations, including for conventional (intercity) passenger rail and for freight rail.  

Proponents of fuel cell trains point to their potential to run over long ranges (up to 1 000 km at a maximum speed of 140 km/h) without refuelling, noting that fuel cell trains do not require spending on catenary lines, making them more competitive with the electrification option when it comes to long-distance low-utilisation routes. They also highlight the potential for quick refuelling times.  

In 2022, Germany started operating 14 hydrogen trains to serve passenger transit over a 100 km track in the state of Lower Saxony, part of a larger order from train manufacturer Alstom totalling 41 trains. In 2023, France ordered 12 hydrogen trains that will soon start test-runs, while the Italian Ministry of Infrastructure and Transport assigned EUR 300 million for the purchase of hydrogen-powered rolling stock and the production, storage and supply of renewable hydrogen. 

Hydrogen projects have often been clustered in advanced economies, which have more financial resources at their disposal to invest in innovative technologies. This past year has seen some emerging and developing economies also investing in hydrogen rail projects, notably India’s 89 km long Sonipat-Jind route, where test-runs are expected to start in December 2023. 

In March 2022, the Japanese JR East has started test runs of the hydrogen-hybrid train HYBARI, which is powered by hydrogen fuel cells and batteries. It is the first heavy train to use high-pressure hydrogen (70 MPa) which increases maximum distance capacity. Spain's CAF, on the other hand, has started dynamic track testing of its own hydrogen fuel cell and battery-powered hybrid train. In Chile, the mining railway Ferrocarril de Antofagasta a Bolivia will introduce hydrogen trains in 2024. 

Clean Tech Guide: Transport, Rail, Biofuels, Refining, Hydrogen. Cross-cutting themes: Direct electrification. 

Following the EU announcement of financial support for the commercialisation of the hyperloop technology, pioneering companies launched the "Hyperloop Association" in December 2022, and a hyperloop testing facility is being set up in Groningen. 

The EU is also funding the development of Railway to Grid management systems via the E-LOBSTER project. The platform could provide a real-time energy flow management between rail, the electricity grid, energy storage and electric vehicle charging station systems, utilising the train's regenerative braking and reducing the grid's distribution losses. A testing tool has been successfully implemented in Madrid, and the innovation was demonstrated and validated at the University of Newcastle. 

Stadler, Utah State University and ASPIRE Engineering Research Center are developing a fully battery electric train, the FLIRT Akku, and have already sold over 110 units and replaced diesel fleets in some places in Germany. The co-operation aims to redesign this train to meet market requirements in the United States. 

China's first domestic magnetic levitation (maglev) line began testing in March 2023. The line will be 38 km long with a first phase of 8 km to open in late 2023. 

A range of recent policies allocate public funding to extend railway infrastructure, modernise fleets and upgrade digital operations (including software and equipment). 

• Lucie Anderton, Joo Hyun Ha, Alice Favre and Philippe Stefanos, International Union of Railways
• Jacopo Tattini, European Commission