The European Union has established a new classification for the different types of hydrogen to replace the traditional colour system, focusing on technical and regulatory criteria. The aim is to guarantee clear traceability and prevent confusion regarding the true environmental impact of each form of production.
In this article we review the five recognised types of hydrogen, together with their characteristics, legal requirements and significance for the future of energy.
Until recently, it was common to use a colour-based system to distinguish between the different types of hydrogen: “green” for renewable, “grey” for fossil, “blue” for any produced with CO₂ capture, etc.
While it was useful as a simplified explanation, the system posed three challenges:
The new classification is therefore based on regulated typologies that are linked to measurable parameters, such as the origin of the energy, the feedstock used and the cuts in emissions that are achieved.
The current European regulation stipulates five broad categories of hydrogen. They are each in keeping with a different production model and they have different implications for the market and sustainability.
This is the strictest category and it sets the standard for sustainability within the European Union. Its main feature is its production by means of water electrolysis, using electricity taken from renewable sources such as solar and wind.
Furthermore, it is regulated by Delegated Regulations (EU) 2023/1184 and 2023/1185, two highly important standards when it comes to clarifying what can be regarded as truly renewable hydrogen.
The first is Delegated Regulation (EU) 2023/1184. This standard lists the conditions the electricity used in hydrogen production must meet in order for it to be considered renewable. It isn’t enough for it to come from solar panels or windmills: it has to be electricity produced by new plants (what’s known as additionality) in the same place and at the same time as it is used in the electrolysis (temporal and geographical correlation), and it has to be reliably demonstrated and documented that the energy is renewable.
The second regulation is Delegated Regulation (EU) 2023/1185, which goes a step further. It establishes that, for it to be accepted as renewable hydrogen or recycled carbon fuel, the production process must reduce the greenhouse gas emissions by at least 70% with respect to a fossil fuel. To verify the above, the standard includes a calculation methodology based on the hydrogen’s entire life cycle, from the feedstock to the end use.
Bio-based hydrogen is produced using biomass or biogenic waste by means of sustainable processes, in other words, ones that meet the sustainability and greenhouse gas emission reduction criteria set out in Directive (EU) 2018/2001 (RED II) and its updates. This includes hydrogen from biogas reforming or biomass gasification, provided that the feedstocks are sustainable.
Its main benefit is its capacity to recover organic waste and by-products of agricultural, forestry and industrial origin, reducing the environmental impact associated with waste management, particularly methane emissions resulting from its decomposition.
This refers to hydrogen produced using non-renewable sources which nevertheless leads to significant emission reductions. The main condition is that it must guarantee at least 70% lower GHG emissions than conventional fossil hydrogen.
For example, this kind of hydrogen is produced by means of nuclear-powered electrolysis or natural gas reforming accompanied by CO₂ capture and storage systems.
It may be a transitional option in countries with access to nuclear or natural gas, provided that the emission reduction threshold is met.
This category includes hydrogen produced using renewable sources without meeting one or more of the RFNBO requirements.
Differences with respect to RFNBO:
One example is hydrogen produced by means of electrolysis connected to the existing renewable electricity grid without demonstrating any additionality.
Although its conditions are less stringent, this type of hydrogen remains relevant as a transitional pathway, and it can contribute to decarbonisation in countries in which the regulatory conditions are still under development.
As for fossil hydrogen, it is produced using non-renewable fuels such as natural gas, coal and oil. The most common process is the steam reforming of natural gas, during which the methane reacts with water to generate hydrogen and CO₂.
Fossil hydrogen therefore fails to meet the rule for a 70% emission reduction compared to traditional fuels, which is the criterion for it to be regarded as “clean”. Although there exist carbon capturevariants, most of the production continues to be emission-intensive, unlike green hydrogen, which is produced with water using renewable energy, without generating any CO₂.
Classification alone is not enough. For hydrogen to be officially recognised as RFNBO, renewable, low-carbon or in any other category, certification and traceability systems must be in place.
Certification is essential because:
This classification of types of hydrogen constitutes a decisive step towards building a sustainable and credible energy market. The European Union will thus ensure that hydrogen investments are geared towards solutions that actually cut emissions and add value to the energy transition.
Within this context, certification will be the key tool that determines which projects prosper and which ones are excluded. Understanding and applying this classification will be a prerequisite for companies, investors and consumers wishing to form part of Europe’s energy future.
