Red Eléctrica de España (REE)

Hydrogen produced from renewable electricity sources, considered a critical component for hydrogen's long-term credibility as a clean fuel.

A hydrogen-fuelled reciprocating engine is an internal combustion engine adapted to burn hydrogen instead of—or in combination with—conventional gaseous fuels to produce mechanical power that drives an electrical generator.[2][9] In the Spanish project, a large multicylinder engine unit built by a supplier such as Wärtsilä is configured to use hydrogen-rich fuel to generate electricity that is then fed into the national grid, demonstrating utility-scale hydrogen engine operation.[1][2] These engines can be based on modified gas-engine designs, incorporating changes to fuel injection, combustion chamber geometry, and control systems to handle hydrogen’s different combustion characteristics.[2][9]

Iberian Peninsula (specific project location within Spain reported as part of an industrial or former thermal power plant site, but not consistently named across accessible public sources)

Large reciprocating engines designed or adapted to run on natural gas today and on hydrogen or hydrogen blends in the future, intended for use in flexible power plants that support high-renewable electricity systems.