The turquoise hydrogen will be used at Repsol’s 100% renewable fuel plant in Castile-La Mancha, set to launch in 2026 with a capacity of 200,000 tonnes per year.

Integrating biohydrogen is expected to cut the CO₂ footprint of its renewable diesel by up to 98% compared to fossil-based fuel.

Repsol said developing biohydrogen is a step forward in producing renewable hydrogen through diverse technologies, “adapted to the needs” of its Puertollano complex.

The announcement comes shortly after the oil and gas giant shelved plans for a 130MW hydrogen project at the complex that was set to supply its Puertollano plant.

Despite the cancellation, a Repsol spokesperson previously told H2 View that the company “remains committed” to the development of hydrogen projects in Puertollano.

“In Puertollano, the intention to invest in this area remains, with ongoing studies to determine the most suitable hydrogen generation technologies for this complex.”

Repsol began producing biohydrogen in 2021, having already demonstrated the technology successfully.

In May 2025, the company announced it had produced 6.5 tonnes of biomethane-based hydrogen at its Cartagena plant.

Here, Repsol used biomethane derived via anaerobic digestion of organic waste to produce hydrogen via existing reformers. The biomethane was purified for use as a natural gas substitute.

Earlier this year, Maribel Rodriguez Olmo, Repsol’s director of Hydrogen, said, “The production of renewable hydrogen from biomethane is a clear example of how we are transforming our industrial complexes into multi-energy hubs.”