Green hydrogen

Green hydrogen is hydrogen produced by the electrolysis of water using electricity from renewable sources. Because the energy comes from clean sources, its production generates near-zero direct emissions, unlike hydrogen made from fossil fuels.

It is seen as one of the most promising levers for the decarbonisation of hard-to-electrify sectors, where other alternatives fall short.

How it is produced and types of hydrogen

Electrolysis splits the water molecule into hydrogen and oxygen using an electrolyser powered by electricity. When that electricity comes from sources such as solar or wind, we call it green hydrogen. It is usually distinguished by colours:

• Green hydrogen: by electrolysis with renewable energy.
• Grey hydrogen: from fossil fuels, usually natural gas, without carbon capture.
• Blue hydrogen: from fossil fuels but with carbon capture and storage.

Regulatory framework in the EU

In the European Union, green hydrogen falls under the concept of RFNBO, the acronym for renewable fuel of non-biological origin. Two delegated acts adopted in 2023, under the Renewable Energy Directive, set the rules:

• The conditions for hydrogen to count as renewable: additionality of the renewable electricity, plus temporal and geographic correlation between electricity production and hydrogen production.
• A life-cycle greenhouse gas emissions methodology, under which emissions must be at least 70% lower than those of a fossil comparator.

To drive production, the EU created the European Hydrogen Bank. Its third auction, called IF25, ran between 4 December 2025 and 19 February 2026 and awarded over EUR 1 billion to 9 projects across 7 European Economic Area countries, with around 1.1 GW of electrolyser capacity and more than 1.3 million tonnes of hydrogen expected over their first ten years. For the first time, this round also covered electrolytic low-carbon hydrogen, and a fourth auction is planned for the end of 2026.

What green hydrogen is used for

Its applications concentrate in sectors that are hard to decarbonise by other means:

• Industry: production of ammonia and fertilisers, steel and refining.
• Heavy transport: long-haul trucks, shipping and other uses where batteries are limited.

In these uses, green hydrogen complements energy efficiency and clean technologies on the path towards net zero emissions. Its rollout also interacts with instruments such as the emissions trading market, since part of the European incentives are funded with revenues from emissions trading.

How Manglai helps you

Integrating green hydrogen into a decarbonisation strategy calls for measuring avoided emissions and the real impact of each project accurately. Manglai helps you quantify your footprint and assess the effect of your energy transition measures. Discover how Manglai can help you plan your decarbonisation.