Chapter 2: Our Approach

A fleet-led approach

We will replace existing trains as they reach the end of their life with either new or with younger trains cascaded from other routes. This is the lowest cost way to maintain the resilience, reliability and continuity of the rail service we provide.

Anticipated life expiry dates for the existing ScotRail trains provide major transition points and are a key driver for the development of this plan. By 2045, the existing trains will all be replaced with zero-emission trains which will guarantee the operational, financial and environmental sustainability of Scotland’s railway.

Replacing a significant number of train fleets comes with many changes for the rail industry as a whole. To do this while maintaining the service for our passengers, we will continue to invest in our existing fleet to ensure they continue to operate safely and reliably until they can be replaced. The first phase of these improvement works to our existing trains is underway and will continue through to 2028.

Service Prioritisation

Our plan will see ongoing changes to train fleets across the network and it is important we do this in a strategic way by prioritising specific services. We have done this based on a range of factors including:

  • Patronage
  • Linking Towns & Cities
  • Freight Opportunities
  • Driving Economic Growth
  • Connections for Tourism, Leisure & Hospitality Sectors
  • Cross Border Linkages
  • Emissions
  • Air Quality

Taking these factors into account we have prioritised our rail services based on three passenger markets: InterCity - Suburban - Rural.

We did this by identifying where the above factors would be most negatively impacted if we were unable to sustain our passenger services. Our approach has identified bespoke solutions for each of these routes.

Our Fleet Solutions

Thanks to the technological advances over the past five years, we have learned a lot more about the options available to us, their applicability to the Scottish network as well as the economics of each option. Train options have been assessed against benefits and costs, capabilities and maturity, to select solutions that meet service requirements effectively and efficiently.

Electric trains have been tried and tested on Scotland’s rail network. We have continued to deliver our programme of electrification which has created and maintained jobs, developed key skills for the industry, and has resulted in innovation and improvements to the unit cost of delivering electrification. We know that new electric trains are popular with passengers through the introduction of Class 380s and Class 385s to the network, this is because these trains provide a quieter, smoother and faster passenger experience.

We have seen the rapid development of two electric technologies that are likely to be sufficiently mature to make a significant impact for passenger services, these are battery-electric and battery only powered trains.

We have identified four potential options for replacing ScotRail trains that are reaching the end of their life. Each of these options are essential for sustaining Scotland’s rail services and realising the Scottish Government’s net zero ambitions.

Electric Trains

Electric trains and sufficient electrification of the network remain the preferred end-state for the main InterCity and Suburban passenger services where there is also a freight market, as this will enable the future operation of electric freight trains.

Electric trains will guarantee the operational, environmental and financial sustainability of our passenger services because:

  • They are more reliable and efficient, thus providing an attractive alternative to the car for passengers.
  • They are a zero-emission alternative to diesel trains and will support the decarbonisation of Scotland’s railway.
  • They operate at a lower cost compared with their diesel equivalent, because they are lighter, cost less to build and are less complex to maintain.

Battery-Electric Trains

The technology to support battery-electric trains on the Scottish rail network has developed at pace. These trains require to be charged whilst the train is running on an electrified section of the route, or from a shore supply when stabled. Where there is no freight market, or as a transitional measure on InterCity routes, the operation of battery-electric trains can deliver the same carbon benefits as a fully electric train while significantly reducing the capital investment required in the short to medium term. These trains will improve the punctuality and reliability of our passenger services, while guaranteeing operational sustainability. Battery-electric trains will also reduce the cost of running the railway, when compared with a diesel train, due to their lower energy, maintenance and operating costs.

Independently-Powered Trains

These are either battery-only or hydrogen-powered trains. Battery-only trains require to be charged during layover periods through facilities at terminus or intermediate stations and at depots. While the mileage per charge of batteries is improving as the technology matures, this makes battery-only trains suitable for short-to-medium distances where they can offer reliable train performance. Given the technological progress that continues to be made, we view battery trains as one of the most viable options for an independently-powered fleet.

Hydrogen also has the potential to play a role here and in collaboration with the University of St Andrews’ Hydrogen Accelerator and Scottish Enterprise, we ran a demonstrator project to convert a retired ScotRail electric commuter train into a hydrogen fuel cell train. The application of this technology on rail networks is not yet proven and its supply chain and logistics are still immature. Therefore, to ensure we can deliver a reliable year-round passenger rail service, we will not be considering a hydrogen-powered fleet until the technology has advanced and the cost-benefit analysis is mature.

Transition Fleets

For InterCity routes, electric trains are the preferred end-state. Where a significant extent of electrification is required on these rail corridors, we may introduce interim solutions to allow flexibility in the pace of electrification delivery which will reduce the impact on passengers and businesses as much as practicable. Fully electrifying these routes in a short period of time would require a capital investment as well as causing significant operational challenges, as large sections of the railway would need to be closed to undertake construction works; this would negatively impact passengers on the InterCity routes.

Financial Sustainability

Financial sustainability is a key feature of our strategy to replace ScotRail trains and sustain Scotland’s rail services. The costs and benefits to the Scottish Government and Scotland’s rail industry have informed our approach and our decisions to replace ScotRail fleets are subject to robust business cases which evaluate the long term funding implications. Firstly, we know from the past five years that budgets are susceptible to external shocks which inevitably puts pressure on the scope of our investment. While we have identified fleet solutions for sustaining the performance of Scotland’s railway it is important that we assess these against ongoing financial constraints. That is why we have developed a plan with deliverable solutions that are financially sustainable.

We know introducing battery-electric trains onto the rail network will require more infrastructure to support these fleets, but we will balance these against available budgets and the wider impact infrastructure interventions can have on passengers.

For example, the physical delivery of electrification must avoid impacting the operational sustainability of our rail services, by reducing the impact on passengers and freight customers as much as is practicable. Undertaking too much disruptive engineering work across the network at the same time would have significant revenue impacts and would diminish the attractiveness of rail.

Planning is already underway to provide depot and stabling facilities to support the introduction of new trains. We are also assessing the case for targeted timetable changes and infrastructure investment to enable and encourage more people onto rail, and to improve the capacity and capabilities of key freight routes. We will assess and appraise the case for these interventions alongside fleet replacement in light of available funding, however, the priority will remain the continued provision of a reliable rail service in Scotland.

Our plan to replace life-expiring rolling stock will yield long-term financial benefits for Scotland’s railway as they are cheaper to operate and maintain compared with their diesel equivalents, particularly because spare parts for our ageing fleet are progressively becoming more difficult and expensive to source, and unplanned maintenance interventions take longer to execute.

Zero-emission trains will also be more punctual and reliable, creating an even more attractive rail service for our passengers which will increase overall demand.

Environmental Sustainability

The long-term plan to replace ScotRail’s diesel trains with zero-emission alternatives will make our railway Net Zero by 2045 and build on our excellent record of providing a low carbon railway. We know that transport emissions would reduce simply by moving from a private car or lorry to a diesel train.

The Scottish Government is already taking action to help encourage modal shift from car to rail by permanently removing peak fares on ScotRail services. This will help existing passengers manage cost-of-living pressures, while also making rail travel more affordable and attractive for car users.

While attracting more passengers to the railway is important, it is essential that we retain them by having trains that they can rely on and that caters to their needs, comfort and convenience. Newer trains will be more reliable than the existing diesel fleet and will provide a better passenger experience through smoother, quieter and faster journeys. Modern trains will meet modern accessibility requirements, to ensure Scotland’s railway continues to be a railway for everyone.

Failure to replace our trains will negatively impact the performance, reliability and attractiveness of rail. This could result in a rise in emissions if people are discouraged from using the railway and back into their cars, which would essentially invalidate the low-carbon credentials of rail travel. We cannot risk this as Scotland and the rest of the world continues to face the impacts of climate change.

We also have a responsibility to tackle the rail sector’s own emissions. The only way to achieve this is through the phased removal of ScotRail’s diesel trains which is the central focus of this plan.

Introducing zero-emission trains will eliminate greenhouse gas emissions from the network and support the drive to improve air quality. Outdoor air pollution is one of the greatest risks to public health, particularly in our industrialised and urban areas. While we recognise that rail emissions are considerably lower than other modes of transport it is important we avoid exacerbating the issue, by providing a resilient rail service that can attract people away from their cars.

Supporting Scotland’s journey to Net Zero by 2045 requires a just transition—an imperative that holds particular significance for our railway. As we modernise the network and introduce new trains, the rail industry will increasingly depend on a skilled workforce, particularly in electrification. To meet this demand, we must collaborate with industry partners to champion skills development and training initiatives that both attract new talent and support our existing workforce.

We support the Rail Skills Academy, which is engaging young people in transformative projects such as the East Kilbride electrification and the Levenmouth rail link. This initiative seeks to addresses current skills gaps and promotes greater diversity within the sector, but also plays its part in delivering the ambitions set out in Scotland’s Just Transition Plan for Transport.

Lastly, we are beginning to see the impacts of a changing climate on our railway with extreme weather events becoming more common. This threatens the resilience of our rail services, and therefore, we have a responsibility to create a more climate resilient railway for our passengers and freight customers. The actions our rail delivery partners are taking to address this can be found in Scotland's Railway Climate Ready Plan. Beyond this, Scotland’s Railway Climate Action Plan outlines the actions our delivery partners are taking to reduce emissions from other sources and create a greener and more climate responsible railway.