A cross-European data investigation by DW and the European Data Journalism Network examined over a decade of data from more than 100 reports, covering 33 cities and 148 sustainability commitments by local authorities and transport operators. The picture that emerges is one of genuine but deeply uneven progress: electric buses now comprise 20% of the fleet in EU capitals and selected cities, up 55% since 2021 — equivalent to 1,234 additional electric vehicles on the road. Yet in 20 out of 31 cities with analyzable data, over 50% of the bus fleet still runs on traditional combustion engines. Copenhagen stands alone as the only EU capital to have nearly fully electrified its bus fleet, with just one vehicle running on biomethane. At the opposite end, Rome, Lisbon, and Nicosia still rely on diesel for more than 90% of their buses, with metros and trams accounting for less than 10% of their public transport fleet. The gap between leaders and laggards is not narrowing fast enough for the EU's target of cutting transport greenhouse gas emissions by 90% from 1990 levels by 2050 — a target the transport sector is uniquely far from meeting, being the only major sector where emissions remain above 1990 levels. EU funding has been the primary accelerant. The jump in electric and alternative fuel buses from 2021 onward tracks directly to EU disbursements, not organic market adoption. Cities like Brussels, an early adopter that initially pivoted to hybrids, are now transitioning again to full electrification — a costly two-step that illustrates how technology uncertainty creates friction. Hydrogen buses, which produce zero tailpipe emissions, remain significantly more expensive to operate than battery-electric alternatives, further complicating procurement decisions. The analysis also surfaces an inconvenient lifecycle truth. Copenhagen's new metro expansion, while fossil-fuel-free in operation, carries enormous construction-phase emissions. As University of Catania transportation researcher Michela Le Pira notes, the long-run CO2 benefits of rail infrastructure outweigh construction emissions — but only over time. Meanwhile, non-exhaust emissions from tire and brake wear have increased 58% over two decades as vehicles have grown heavier, partially offsetting gains from stricter tailpipe standards that cut fine particle emissions from buses by 92% since 1992. The deeper structural problem is modal shift. Private automobiles still account for more than a third of trips in the largest EU capitals. Public transport handles more than a quarter of trips in the 10 largest EU capitals on average, ranging from 49% in Stockholm to just 11% in Ljubljana. Only four cities have explicitly committed to achieving zero emissions across buses or all public transport. The electrification of buses is necessary but insufficient — without getting people out of cars, the emissions math does not close. Road transport contributes about 14% of fine particulate matter concentrations in European urban areas and nearly a quarter of EU transport greenhouse gas emissions come from towns and cities. In 2023, almost 300,000 deaths across the EU were attributable to air pollution exceeding WHO thresholds. The human cost of inaction is not abstract — it is the specific gap between a city like Copenhagen and a city like Rome, measured in diesel particulates and respiratory outcomes. Cheaper group ticket pricing, low-emission zones, and multimodal integration — combining bikes, trains, and buses into seamless networks — represent the complementary policy toolkit. But the analysis reveals a commitment gap: most cities have not formally pledged zero-emission public transport, even as EU-level targets demand it. The infrastructure is being built with public money; the political commitments to use it fully are not keeping pace.
