The Renewable Heat Obligation (RHO) is a new policy measure designed to decarbonise the Irish heat sector by requiring fossil fuel suppliers to include a rising proportion of renewable heat—particularly biomethane—within their energy mix. The scheme forms part of Ireland’s Climate Action Plan and aligns with RED III (Renewable Energy Directive III) principles on sustainability and greenhouse gas reduction.

Biomethane, as the flagship renewable fuel under the RHO, must meet strict GHG and land-use sustainability criteria in order to qualify for compliance and contribute towards an obligated supplier’s renewable heat targets.

RHO Sustainability Criteria

The sustainability criteria under the Renewable Heat Obligation consist of two key elements:

1. Greenhouse Gas (GHG) Emissions Criteria
   Obligated suppliers must ensure that renewable fuels used for compliance—such as biomethane or advanced biofuels—meet strict GHG lifecycle thresholds. These thresholds are designed to ensure a significant net reduction in emissions compared to fossil fuels. Fuels must be calculated according to the RED III methodology, which considers feedstock production, processing, transport, and combustion. While the exact GHG limit under RHO is subject to final regulatory confirmation, it is expected to align with RED III benchmarks and build upon the thresholds used under the UK’s GGSS and RHI.
2. Land Use Criteria
   Feedstocks used in renewable heat must not come from land that:

• Was primary forest at any time since January 2008;
• Was designated for nature protection (unless production of the material did not compromise those designations);
• Is or was highly biodiverse grassland, unless appropriate and sustainable harvesting is in place;
• Is or was peatland, unless no drainage occurred;
• Is a former wetland or continuously forested area converted to crop production since 2008.

Where feedstocks are waste or residues from processing (e.g. slurries, distillery residues, or food industry byproducts), the land criteria is deemed to be met, but full traceability and documentation must still be maintained.

RHO Compliance for Heat Fuel Suppliers

Fuel suppliers who fall under the scope of the RHO will need to demonstrate annually that their renewable heat volumes meet the sustainability criteria in order to be compliant and avoid penalties. Certification of fuels, sustainability statements, and third-party audit documentation are expected to form the basis of compliance monitoring by the scheme administrator, NORA (National Oil Reserves Agency).

Envirosense® Verification & ISAE Assurance

At Envirosense®, we provide independent third-party sustainability audits to meet the compliance requirements of the Renewable Heat Obligation in Ireland. Our clients range from major fuel distributors to small-scale biomethane producers. Drawing on over a decade of experience with RHI, RO, and GGSS assurance work in the UK, we are now applying that expertise to help Irish fuel suppliers prepare for the RHO.

Our RHO audits are conducted in accordance with the International Standard on Assurance Engagements (ISAE 3000), the globally recognised framework for verifying non-financial disclosures such as carbon reporting and sustainability compliance. Envirosense® was among the original pilot auditors with Ofgem and has been a trusted name in RED II/III-based verification since 2012.

We work directly with obligated parties under the RHO to:

• Review your renewable fuel supply chains;
• Verify greenhouse gas lifecycle calculations;
• Assess compliance with land-use sustainability rules;
• Prepare audit-ready documentation in line with NORA and government expectations;
• Deliver robust, regulator-ready ISAE assurance reports.

If you are a fuel supplier preparing for your RHO compliance obligations, contact Envirosense® to ensure your sustainability audit is completed accurately, efficiently, and professionally by a team with deep sector expertise.