Wärtsilä runs world’s first large‑scale 100% hydrogen engine on Spain’s grid

Finnish energy firm Wärtsilä demonstrated its 31H2 engine running on 100% hydrogen, delivering power to the national electricity grid in the town of Bermeo, northern Spain. The company says the test is the world’s first large‑scale pure‑hydrogen fuel engine operating under real grid conditions, moving beyond earlier hydrogen‑ready or mixed‑fuel systems. The demonstration shows that excess wind and solar power can be stored as hydrogen via electrolysis and later used for carbon‑free electricity generation, offering a flexible backup for intermittent renewables. Wärtsilä highlighted Spain’s high renewable capacity and goal to cut fossil‑fuel imports, and noted potential uses in grid balancing, remote locations, heavy‑industry sites and AI data centres.