Renfe and Repsol have completed an initial operational trial using hydrotreated vegetable oil (HVO) to power the Costa Verde Express, advancing efforts to cut emissions on Spain’s non‑electrified rail routes.
A Series 619 locomotive was fully drained of conventional diesel before being refuelled at El Berrón depot in Asturias with 1,000 litres of Repsol’s ‘Nexa’ renewable HVO‑blended diesel.
The locomotive then hauled the Costa Verde Express, part of Renfe’s Luxury Trains portfolio, which operates a six‑day, five‑night itinerary between Santiago de Compostela and Bilbao.
Renfe said the test run confirmed the technical viability of HVO in live passenger operations. The operator and Repsol have now signed a protocol to promote HVO as an alternative to fossil diesel across Spain’s remaining diesel‑worked routes.
While 94% of Renfe’s passenger demand in 2025 was met using carbon‑neutral electric traction, around 6% of services — typically on rural or remote lines — continue to rely on diesel. The HVO trial forms part of Renfe’s 2024 Sustainability Master Plan, which includes targeted measures to reduce emissions on unwired sections of the network.
Renfe and Repsol validate HVO use on Costa Verde tourist trains
