Wärtsilä tests world’s first large-scale 100 per cent hydrogen engine

• a day ago (2026-06-11)
• David Flin

Europe 1170 Gas engine plant 93 Hydrogen 76

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Wärtsilä has announced that it has started validation of a new 100 per cent hydrogen engine intended to power Spain’s national electricity grid in Bermeo, northern Spain. This will be the world’s first demonstration of a large-scale 100 per cent hydrogen engine.

The Wärtsilä 31H2 four-stroke engine is currently being verified in Bermeo, and is the world’s largest pure hydrogen engine.

Rasmus Teir, Director of Technology Strategy and Decarbonisation at Wärtsilä said: One of the biggest challenges facing the energy transition is how to maintain reliable electricity supplies sustainably during periods of low renewable generation or spikes in demand. Our Wärtsilä 31H2 hydrogen engine is operating on 100 per cent hydrogen and supplying power to Spain’s national grid. We have proven the technology is ready.”