Decarbonising railway stations: the challenges of retrofitting iconic buildings to achieve net zero emissions

Introduction

Trains have long captured the public imagination as symbols of mobility and progress. Rail transport has evolved over generations to drive social and economic growth, from classic steam locomotives belching smoke to sleek electric bullet trains. In recent decades, electrifying mainline routes has started decarbonising rail infrastructure – but the journey is far from complete. Approximately 15% of the rail operational emissions can be associated with non-traction activities, with about 40-50% associated with stations and other buildings. Railway stations remain primarily rooted in the past, relying on carbon-intensive power. With over 2,500 stations in the UK, transforming these public hubs represents a monumental task on the road to net-zero carbon emissions.

Yet, the slow progress made on decarbonising stations threatens rail’s sustainability goals. As major energy consumers, these buildings account for a significant portion of the sector’s overall emissions. From powering lights, signals, and displays to heating cavernous spaces, stations exert colossal power demands around the clock. Taking the Bristol Temple Meads as an example, the electricity demand was at 5.8 TWh and 6.0 TWh, resulting in approximately 1,370 tCO2 and 1,280 tCO2e emitted in 2021 and 2022. It is worth mentioning that such figures seem to be independent of the number of passengers using that station, estimated by the Office of Rail and Road to be approximately 2.0m in 2021 and 6.6m in 2022.

Modifications are necessary to reduce the stations’ footprint now. Yet, upgrading ageing electrical, heating, and cooling systems requires overcoming daunting challenges. Many stations date back over a century, and balancing preservation with needed upgrades is complex. Considering that the UK government plans to fully decarbonise the electricity supply by 2035, the question remains whether the stations should now invest in low-carbon energy supply, such as PV panels and heat pumps, or offset their emissions while waiting for the grid to become decarbonised.

Moreover, rail stations are often considered important commercial and community hubs. Any disruptive renovation can pose a threat to their role as economic and social centres. However, solutions are available to ensure these stations remain sustainable and functional. Notably, the public-facing nature of these spaces makes them an ideal setting to showcase carbon-reduction technologies in action.

Reducing scope 1 and 2 emissions

Transitioning stations to renewable energy is a massive yet crucial undertaking. Solar panels can be mounted on station rooftops or over platforms to generate clean electricity. Converting heating and cooling systems from boilers and furnaces to electric heat pumps slashes fossil fuel usage. Moreover, intelligent energy management platforms are critical for optimising power consumption minute-by-minute and avoiding waste from excessive heating or lighting.

Smaller rural stations can pursue completely net-zero operations through 100% renewable energy sources. This can be achieved by meeting their energy demands through on-site solar PVs on the station and platform roofs. This is also, to some extent, applicable to larger stations. For example, London Blackfriars underwent extensive revamping to integrate solar and heat pumps into a strikingly modern station design. The array of 4,400 PV panels currently generates approximately 0.9 TWh of green electricity each year, accounting for about 50% of the station's electricity consumption. This reduces the station’s Scope 2 emissions by nearly 0.5 tCO2 per year. The prominent sustainability upgrades match the forward-looking redevelopment transforming the surrounding district.

Decarbonising larger stations may be more challenging, especially when historic appearance needs to be preserved, as in the case of the Bristol Temple Meads. Rather than waiting, such stations with heavier demands can purchase verified carbon credits to offset any lingering fossil fuel reliance as the energy infrastructure is decarbonised.

Mitigating scope 3 emissions are critical to net zero

Alongside decarbonising stations themselves, through the reduction of scope 1 and Scope 2 emissions, encouraging and enabling low-carbon transport options for passengers and staff to access stations is critical to reducing Scope 3 emissions. This behavioural shift eases congestion while making station surroundings more liveable.

Incentivising public transit use through discounted fares and transition to low-carbon fuels reduces reliance on polluting cars. For example, for a single person travelling from home to the train station, the average car would result in 170 gCO2e/km, whereas the average local bus would result in 102 gCO2/km. Therefore, prioritising bus lanes, implementing e-scooter routes (with appropriate certification), and secure bike parking would facilitate the reduction of the station's Scope 3 emissions. Promoting e-scooters, cycling, and walking for historic city-centre stations offers carbon-free accessibility.

Commuting to work can also have a significant impact on the environment. Railway employees have a unique opportunity to contribute to decarbonising the workforce, leading others by example. For example, train station crews could reduce their carbon footprint while commuting by using crew buses or participating in car-sharing schemes. These options will also help reduce the number of vehicles on the road, reduce traffic congestion, and lower overall emissions.

Stations could also consider investing in electric vehicle (EV) charging stations at their facilities to support the further adoption of eco-friendly transportation methods. This would make it easier for employees to transition to EVs and reduce their reliance on traditional vehicles. Additionally, railway companies could encourage their employees to switch to more sustainable transportation options by offering salary-sacrifice schemes that provide tax incentives for using EVs.

By implementing these measures, railway companies can demonstrate their commitment to reducing environmental impact and encourage employees to do the same. Together, these efforts can help to create a cleaner, more sustainable future for everyone.

Sustainable materials for new stations and extensions

Stations’ sustainability relies on operational energy use and the carbon footprint of maintenance, renovation, and construction. Materials science innovations allow increased use of greener components like recycled metals or lower carbon concrete blends. This has been proven to be a viable approach to new developments and retrofits of existing buildings.

Thoughtful design maximises the reuse of existing materials while minimising waste. Sourcing raw materials locally further shrinks supply chain emissions. For example, the new building for the Net Zero Industry Innovation Centre has achieved the BREEAM “outstanding” certification, is net zero in operation, and only 650 kgCO2e needs to be offset per m2. Robertson, the building developer, achieved this by using a low cement concrete mix, 100% recycled steel, and ensuring that the materials are locally sourced. Moreover, the builder used hydrotreated vegetable oil, which is synthesised from renewable raw materials, that allowed for the reduction of the greenhouse gas emissions associated with energy demand during the construction by 90%

Adopting low-carbon methods showcases sustainability, reduces waste, and cuts costs. Research indicates holistic approaches considering emissions from start to finish could reduce infrastructure projects’ carbon by at least 20-50%.

Conclusion

Railway stations have the opportunity to lead the way in delivering net zero transition, despite their challenges. These iconic landmarks, which are an integral part of our communities, can demonstrate innovative approaches to climate change. The shift towards net-zero emissions is not just good for the environment, it also enhances passenger experiences, drives economic growth, and preserves historic sites.

The rail sector has a history of driving progress during times of change. By embracing sustainable practices, the sector can lead towards a brighter future. The journey ahead may be extended and challenging, but each step brings us closer to a more sustainable future in transportation.

This article is based on research conducted within a project funded by the Innovation Launchpad Network+. illuminem Voices is a democratic space presenting the thoughts and opinions of leading Sustainability & Energy writers, their opinions do not necessarily represent those of illuminem.