The legal framework
The Renewable Energy Directive (RED II, amended by RED III, Directive (EU) 2023/2413) sets the targets. Two delegated regulations set the method: Delegated Regulation (EU) 2023/1184 defines when the electricity used is renewable, and Delegated Regulation (EU) 2023/1185 sets how to calculate the greenhouse-gas savings.
Only hydrogen that meets both acts counts towards the EU renewable targets for industry and transport. Hydrogen that does not meet them can still be sold, but not as RFNBO.
Three ways to source the electricity
Direct connection
The electrolyser is connected to a renewable plant that came into operation no earlier than 36 months before it, and that plant is not connected to the grid, or it is and a smart meter shows no grid power was used. The transitional exemption described below does not apply to this route.
Grid with a high renewable share
If the bidding zone had more than 90% renewable electricity in the previous calendar year, grid power counts as renewable for a limited number of full-load hours.
Grid with a renewable PPA
The producer buys renewable power through power purchase agreements and meets the additionality, temporal and geographic correlation rules. A further option applies in low-carbon zones where the grid emission intensity is below 18 gCO2e/MJ.
Additionality: new renewable capacity
The renewable plant behind the PPA must have come into operation no earlier than 36 months before the electrolyser, and must not have received operating or investment aid.
There is a transitional exemption for this grid route: electrolysers that come into operation before 1 January 2028 do not have to meet these two conditions until 1 January 2038. Capacity added after 1 January 2028 is not covered, and neither is a direct connection, which always needs the 36-month window.
Temporal correlation: monthly, then hourly
Until 31 December 2029, renewable generation and hydrogen production must match within the same calendar month. From 1 January 2030 the match becomes hourly.
Member States may apply hourly matching earlier, from 1 July 2027. Power stored in a battery behind the same meter can also count if it was charged in the same period.
Geographic correlation: the bidding zone
The renewable plant must be in the same bidding zone as the electrolyser, in an interconnected zone with an equal or higher day-ahead price, or in a connected offshore zone.
Many countries are a single bidding zone, which makes this rule easier to meet inside the country than across borders.
The 70% emissions test
RFNBO must emit at least 70% less than the fossil fuel comparator of 94 gCO2e/MJ. In practice the life-cycle emissions must be at or below 28.2 gCO2e/MJ, about 3.4 kgCO2e per kg of hydrogen.
The calculation covers the electricity, inputs, processing, transport and distribution. Grid electricity that does not meet the renewable rules is counted with the grid emission factor, so a small share of grid power can push a project over the threshold.
gCO2e/MJRFNBO threshold (70% saving): 28.2
Why it matters: the RED III targets
By 2030, at least 42% of the hydrogen used in industry must be RFNBO, rising to 60% by 2035. In transport, advanced biofuels and RFNBO together must reach 5.5% by 2030, with at least 1% from RFNBO.
These targets create the demand for certified hydrogen, and offtake contracts and subsidies such as the European Hydrogen Bank usually require RFNBO compliance.
How compliance is certified
Compliance is shown through voluntary certification schemes recognised by the European Commission, such as ISCC EU or CertifHy. An auditor checks the PPAs, metering data and the emissions calculation.
Importers to the EU must meet the same rules, so projects outside the EU that plan to export need certification too.
Key dates
1 July 2027
Member States may require hourly temporal correlation
1 January 2028
Electrolysers in operation from this date must meet additionality from the start
1 January 2030
Hourly temporal correlation becomes mandatory
2030
Targets: 42% RFNBO in industrial hydrogen; at least 1% RFNBO in transport
2035
Industry target rises to 60%
1 January 2038
End of the additionality exemption for early electrolysers
Worked example
A 10 MW electrolyser comes into operation in 2027. It buys power through a PPA with a solar plant that came into operation 20 months earlier in the same bidding zone, without public aid. The 36-month rule is met, and in any case the project is exempt from additionality until 2038.
Production and solar generation are matched each month. With life-cycle emissions of 12 gCO2e/MJ, the saving is 87% and the hydrogen is RFNBO. If grid power raised emissions to 30 gCO2e/MJ, the saving would be 68%, below 70%, and the hydrogen would not count as RFNBO.
Frequently asked questions
What does RFNBO stand for?
Renewable fuel of non-biological origin: hydrogen and hydrogen-based fuels such as ammonia or e-methanol, made with renewable electricity and not from biomass.
Is RFNBO the same as green hydrogen?
Not exactly. Green hydrogen is a market term with no single definition. RFNBO is the EU legal definition, with specific electricity and emissions rules.
What is the emissions threshold for RFNBO?
At least a 70% saving against 94 gCO2e/MJ, which means no more than 28.2 gCO2e/MJ over the life cycle.
When does hourly matching start?
On 1 January 2030. Member States may apply it from 1 July 2027.
Until when are early projects exempt from additionality?
Electrolysers in operation before 1 January 2028 are exempt until 1 January 2038.
Does hydrogen imported into the EU have to be RFNBO?
To count towards EU targets, yes. Imported hydrogen must meet the same rules and be certified under a recognised scheme.