Technology group Wärtsilä has begun validation of the world’s first large-scale 100% hydrogen engine in Bermeo, northern Spain, marking a significant milestone in the global transition toward fully renewable power systems. The trial, using the Wärtsilä 31H2 engine — the world’s largest pure hydrogen engine — is being conducted to power Spain’s national electricity grid and demonstrates that large-scale engine technology can operate entirely on sustainable fuels such as hydrogen.
The Wärtsilä 31H2 is part of the Wärtsilä 31 platform, one of the world’s most efficient multi-fuel four-stroke engines. It builds on the company’s earlier launch of the world’s first large-scale 100% hydrogen-ready engine power plant and on a 2022 demonstration in which Wärtsilä and WEC Energy Group successfully ran an unmodified Wärtsilä 50SG engine on a 25% hydrogen blend at a 55 MW power plant in Michigan, USA. Wärtsilä’s engines today can already operate on natural gas blended with up to 25% hydrogen by volume, a capability increasingly reflected in power generation tenders globally.
The milestone carries particular significance for India, which is targeting 500 GW of non-fossil fuel electricity capacity by 2030 and advancing its National Green Hydrogen Mission to establish itself as a global hub for the production, utilisation, and export of green hydrogen. As renewable energy penetration increases, hydrogen-capable engine technologies can provide the flexible, dispatchable power needed to maintain grid stability and enable greater integration of renewables at scale.
India is also witnessing rapid growth in data centres, advanced manufacturing, and industrial production — all driving higher demand for reliable, flexible, and sustainable electricity. As AI-led data centre investments accelerate across the country, technologies capable of delivering dispatchable low-carbon power will become increasingly valuable.
Mr. R. Venkatesh, Managing Director of Wärtsilä India, said: “India is entering a defining decade in its energy transition. With the government’s strong focus on renewable energy expansion and the National Green Hydrogen Mission, technologies that complement renewable generation while strengthening grid reliability will become increasingly important. Wärtsilä’s demonstration of a large-scale engine operating on 100% hydrogen reinforces our commitment to supporting India’s transition towards a cleaner, more resilient, and future-ready, low-carbon energy ecosystem.”
While the validation is being conducted in Spain, the learnings from the demonstration are expected to advance Wärtsilä’s hydrogen roadmap globally, including in India, where expanding renewable energy capacity and growing green hydrogen investments are creating new opportunities for flexible, low-carbon power generation.