"Decarbonising Buses" by Jude Balfour, Decarbonisation Delivery Programme Manager at First Group: Monday 10 July 2023

FirstGroup is publicly committed to operate a zero emissions bus fleet from carbon-neutral depots and facilities by 2035. No new diesel vehicles have been purchased since December 2022, and FirstBus has an ambitious decarbonisation roadmap to grow its business, capability and employment opportunities.

FirstGroup was ranked third out of the world's ninety most influential transport companies in the World Benchmarking Alliance's 2022 Transport Benchmark, making it the top performing UK transport company. As part of its strategy development, it has tested a wide range of technologies: hydrogen buses in Aberdeen, biogas in Bristol, turnkey Battery Electric Vehicles in Leeds, AC BEVs in York, DC BEVs in Glasgow.

FirstGroup's modern purpose-built Caledonia Depot occupying 16 acres either side of the M74 on the south side of Glasgow is the UK's largest, with a capacity of 430 internal combustion or electric vehicles. Overnight charging is by Heliox CCS dual-headed 120/150 volt DC chargers that support fleets of ADL Enviro 200 and Enviro 400 electric vehicles.

Transport Scotland drove ambitions for Zero emissions, enabling all civil engineering for the first phase to be completed in September 2021. A second phase requiring 69 more chargers was completed in advance of vehicle delivery completed in February 2023, taking the total to 150. Partnership working with DNO and Hitachi has prepared for a trial of Business to Business charging this autumn for parcels delivery giant DPD and for Police Scotland.

Preparations for Zero Emission Buses comprised infrastructure provision, with power brought to site plus charger commissioning, and vehicle procurement for which options included purchase or lease of the complete vehicle or its battery. Telematics configuration could embrace staff monitoring and Smart charging.

With the above-noted options for power sources, considerations of vehicle suitability might embrace network geography, battery size, journey quality and additional software requirements. Stakeholders to be brought on board comprised engineering and driver colleagues, local and central government, private organisations, investors and local communities. The charging model could provide for on or off-site options with opportunities to charge other people's vehicles and the choice between AC and DC. The charging infrastructure must take account of power availability, plugs, sockets, charger types, provision for sub stations, the lifespan and maintenance of chargers and management systems for them. Depot location may have to reflect geographical range of operation, the structure of routes, energy availability, space and planning requirements.

Smart charging is an opportunity to take advantage of grid balancing, grid shaving, variable energy tariffs, fault management and maintenance possibilities, which must take account of skills ratios, training and warranties. The financial model should consider the costs of the vehicle and of electricity, infrastructure, maintenance, energy and operations. Safety considerations must apply to use of HV batteries and hydrogen. Partnership opportunities may arise in turnkey solutions and business to business trading. Battery storage and generation require careful provision.

The impact that buses can have goes far beyond just commercial value : consider the environmental benefits of the recent 14% increase in passenger numbers, which equates to over 1689 tonnes of carbon dioxide removed from the planet each year and to 34136 hours saved for car-users who can work, read or relax instead of having to drive.

For FirstGroup across the UK, over 600 electric vehicles have been delivered at nine locations representing 15% of the fleet. Lessons from the Caledonia experience are being implemented elsewhere, and full depot decarbonisation can be looked at through spending time with the ambulance service and looking at full depot decarbonisation through renewable solutions with knowledge-sharing and partnership working.

Report by John Yellowlees. Photograph by John Fender