Decarbonizing Aviation Ground Operations 2025

Airport bus solutions: Technology overview and developments2 Ground transport – particularly bus fleets – has become a key focus for airports seeking to reduce operational emissions and advance sustainability goals. Rapid technology developments are driving a reassessment of fleet strategies and the adoption of innovative solutions. This chapter provides an overview of the main technological pathways considered for the TCO analysis that are shaping the future of airport bus operations, including battery-electric, hydrogen fuel cell and retrofitted diesel vehicles with battery- electric powertrain. Renewable biofuel (hydrotreated vegetable oil, or HVO) and biomethane buses, although not considered in the TCO model, have also been assessed. By examining the operational characteristics, infrastructure requirements and decarbonization potential of each option, this chapter aims to equip decision-makers with the insights needed to navigate the complex landscape of technology options and align investments with both immediate needs and long-term climate objectives. The decarbonization of airport bus fleets is increasingly shaped by three primary technologies: battery-electric, hydrogen fuel cell and retrofitted diesel. Each option offers distinct operational characteristics and infrastructure requirements, making its suitability dependent on the specific operational context of the airport. While their shared objective is the reduction of greenhouse gas emissions and local pollutants, the underlying technologies differ significantly in energy storage, refuelling or recharging methods, and performance profiles. Understanding the core features of each technology and weighing it with financial considerations can enable decision-makers to achieve a full techno- economic picture guiding strategic investment. Electric buses Battery-electric buses draw propulsion energy from high-capacity lithium-ion or, in emerging cases, solid-state batteries, offering zero tailpipe emissions and high energy efficiency. Their primary advantage is the relative maturity of the technology thanks to the rise of EVs in the automotive industry, and the rapidly expanding supply chain, which has driven down procurement costs and improved performance. Electric buses are particularly well-suited to airports with compact layouts, predictable routes and scheduled breaks that align with charging opportunities. Overnight depot charging is often sufficient for landside shuttle services, while high-power opportunity charging can support airside operations with higher duty cycles. However, battery-electric technology is not without limitations. Range and battery lifetime can be affected by ambient temperature, heavy passenger loads and continuous use of auxiliary systems, with performance degradation more pronounced in extreme cold or heat. Charging infrastructure requires careful integration with airport power systems to avoid grid strain, potentially necessitating upgrades to accommodate the rising energy demands, or the deployment of energy storage solutions at airports. In addition, strategies for end-of-life battery management and disposal remain a critical consideration; some airports are already adopting “second-life” applications,6 repurposing retired batteries for stationary storage, which can help mitigate environmental and logistical challenges if properly implemented. Airports implementing electric buses must consider the operational fit, route length, fleet size and the ability to coordinate charging with operational peaks. Electric buses have seen rapid adoption, especially in European airports such as Aeroporti di Roma, where renewable energy powers 11 fully-electric shuttle buses,7 or London Gatwick,8 which will entirely replace its 14-bus fleet with fully electric buses. 2.1 Technology options Decarbonizing Aviation Ground Operations: Alternative Bus Technologies 9