Ben Warren
RSSB Emissions Principal, Sustainable Development
Being sustainable costs more, right? It’s a common perception. But not the correct one. There are many ways that our RSSB work has shown that being more sustainable will save the industry money. Consideration of immediate investment and operational requirements is crucial. Energy, emissions, and cost are closely related.
There are some relatively easy wins, where reducing costs also has positive environmental impact. One success, illustrated in the September 2025 edition of Expert Edit, is the reduction of train engine idling. This is a measure that can be taken immediately and relatively simply by engaging with operational teams. The result is a cut in emissions leading to an improvement of air quality, alongside lower energy use with a cost saving on fuel. It also helps us to be a better neighbour by reducing noise.
Other activities have required a bit more initial investment. For instance, current research is identifying battery power as an alternative to diesel. We’re working closely with GWR on a fast-charging battery system. We’re learning a lot about how rail services can operate effectively with this different form of traction. And this research is helping us consider afresh what a resilient rail network actually needs. Battery trains may be cheaper than more extensive electrification, but are they the right solution?
Effective decision-making
Different decisions will be made if the emissions and cost across the whole life of an asset are evaluated as part of the decision-making process. Battery trains will be cheaper in the short-term. Network electrification will be cheaper over the life of the track. Batteries are less energy-efficient than Overhead Line (OLE), and heavier and therefore increase the need for track maintenance. They are also more technically complex and expensive to maintain. On top of this, there are sustainability issues with the supply of raw materials for batteries.
Rail needs a way of identifying what is really the most effective thing to do for the longer term. ‘Whole-life’ thinking, not just immediate or short-term benefits, helps us do that.
Managing carbon
This approach is fundamental to our new Carbon Management Tool. To illustrate, some key design decisions for enhancements have surprising answers.
For example, it may seem better to buy the more expensive low-carbon steel produced in an electric arc furnace from scrap steel. But there may be an even better solution. Creating designs that use less steel. This can both save money and help sustainability.
Similarly, it may seem that a section of track with a lower tension OLE is cheaper and lower cost than a stronger OLE set-up.
But the stronger system needs fewer masts, so the cost and embodied carbon can be lower.
To sum up, there are clear relationships between emissions, energy, and costs. These interactions play out across the life of an asset. This can be as long as hundreds of years. To really progress with sustainability, we need to understand how assets will be used in these timeframes. Our tools and research help the industry to understand these interactions.
This thinking will achieve long-term goals like net zero 2050. More importantly, it will create a railway that makes sure that the money that is invested is being spent most effectively.