Zemo Partnership Launches RFAS Aviation to Verify UK SAF Traceability

The Zemo Partnership has launched a new voluntary assurance program, RFAS Aviation, to provide independent verification for Sustainable Aviation Fuel (SAF) supplied in the United Kingdom. The scheme, announced on March 30, 2026, is designed to enhance the credibility and traceability of sustainability claims as the UK's SAF mandate comes into effect.

The initiative extends the established Renewable Fuels Assurance Scheme (RFAS), which has a history in the road transport sector, to the aviation industry. Its primary function is to create a robust, auditable chain of custody for SAF. This verification is critical for airline operators, fuel suppliers, and regulators who must comply with the requirements of the UK Emissions Trading Scheme (UK ETS). By providing a standardized SAF Declaration, the RFAS Aviation scheme aims to prevent issues such as double-counting of emissions reductions and ensure that sustainability data is consistent and reliable.

According to the Zemo Partnership, the first fuel supplier to receive approval under the new framework is Valero Energy Limited. This approval marks a key step in building a verified supply chain ahead of escalating regulatory requirements.

Regulatory Framework

The launch of RFAS Aviation is directly linked to the UK's ambitious aviation decarbonization policy. The UK Department for Transport (DfT) has implemented a SAF mandate that legally requires an increasing percentage of SAF to be blended with conventional jet fuel. According to the DfT's SAF Mandate, the requirement begins at 2% of total fuel supply in 2025, rising linearly to 10% by 2030 and 22% by 2040.

This mandate creates a guaranteed market for SAF but also necessitates a rigorous system for tracking and verifying its sustainability credentials. RFAS Aviation is designed to meet this need by aligning with the sustainability and chain-of-custody criteria of the UK ETS. Verified SAF Declarations issued under the scheme will allow airlines to confidently claim Greenhouse Gas (GHG) reductions and meet their compliance obligations.

Gloria Esposito, Director of Sustainable Business at Zemo Partnership, stated that RFAS Aviation provides the independent verification needed to give airlines, suppliers, and regulators confidence in SAF traceability and sustainability. She highlighted that collaboration with the Environment Agency ensures SAF Declarations align with UK ETS requirements.

Industry Impact

The introduction of RFAS Aviation will have a significant impact on several key stakeholders. For UK airline operators, the scheme provides a clear mechanism to demonstrate GHG emissions reductions under the UK ETS, potentially lowering compliance costs and reputational risk. It standardizes the evidence needed to prove the use of qualifying SAF.

SAF suppliers like Valero Energy Limited benefit from a standardized process to evidence the sustainability of their products to customers. This facilitates market access and ensures compliance with the national mandate, which is crucial for securing offtake agreements. For conventional jet fuel distributors, the scheme necessitates the integration of new traceability and tracking systems from the point of blending all the way to the airport wing-tip.

The UK Environment Agency, which oversees the UK ETS, benefits from a harmonized and auditable record-keeping system. This simplifies regulatory oversight and helps prevent the misattribution of sustainable fuel across different markets or the double-counting of emissions benefits.

Technical Analysis

The establishment of the RFAS Aviation scheme is a foundational step in the operationalization of the UK's aviation decarbonization strategy. While mandates create demand, assurance schemes create the market's trust and functional integrity. This development follows a pattern seen in other jurisdictions, such as the EU's ReFuelEU Aviation mandate, where regulatory targets are paired with verification mechanisms. The UK's extension of its existing RFAS from road to air transport is an efficient use of established frameworks, potentially accelerating adoption.

However, industry analysts note that the success of the UK SAF mandate hinges on the ability of the supply chain to scale. While the mandate targets 10% SAF by 2030, some critics warn that supply of sustainable feedstocks may not keep pace, leading to high buy-out costs for airlines. Furthermore, environmental groups continue to stress the importance of strict feedstock verification to avoid issues like indirect land-use change, a concern that schemes like RFAS Aviation are designed to address directly through auditable chain-of-custody requirements.

What Comes Next

The UK's SAF policy includes several key future milestones that will drive further demand for verified fuel. The government has confirmed the introduction of a specific sub-obligation for Power-to-Liquid (PtL) SAF, a type of synthetic e-fuel. This sub-mandate will begin at 0.2% in 2028 and increase to 3.5% by 2040.

The broader SAF mandate will continue its linear progression, reaching the critical 10% blending requirement by 2030. As these targets approach, the role of RFAS Aviation in verifying a growing and diversifying pool of SAF types will become increasingly important for the entire UK aviation sector.

Why This Matters

The RFAS Aviation scheme is more than an administrative process; it is a critical piece of market infrastructure for the UK's aviation industry. It provides the foundational layer of trust and accountability necessary for airlines to invest in SAF offtake agreements and for suppliers to invest in production. For the UK government, it ensures its flagship decarbonization policy is credible and its emissions reduction targets are met with verified, sustainable fuels.