Relevant for ship owners and managers.

Fuel allocation and certification

Two guidelines have recently been completed by the European Sustainable Shipping Forum (ESSF) and are now published. The two guidelines are:

1. Report on calculation methodologies under Regulation (EU) 2023/1805 (FuelEU)
First, a recently published report on calculation methodologies under FuelEU provides guidance and best practices to understand and implement the calculation as set out under the regulations. The guideline provides crucial information to those calculating the actual vessel performance. We recommend that our customers familiarize themselves with the report, in particular with the principles of fuel allocation under FuelEU, as illustrated below.

Illustration of the most beneficial fuel allocation within the FuelEU energy scope (source: DNV white paper on FuelEU Maritime)

While the illustration has been taken from the DNV white paper on FuelEU Maritime, its content is consistent with the one provided in the report of calculation methodologies under FuelEU (note: DNV has actively contributed to the development of the ESSF report). The ESSF report additionally provides guidance on the regulation’s technical requirements, including the use of renewable and low-carbon fuels, voyage specific exemptions, and flexibility mechanisms such as banking, borrowing and pooling. See the “Resources” section below featuring a link to the report. More guidance from the European Commission is expected in the second half of 2025.

2. Report on Marine Fuels Certification Procedures to support implementation of FuelEU Maritime
The second key guideline is relevant both to FuelEU Maritime and the EU ETS. One of the key topics covered in this report is fuel sustainability certification. The document provides a template for Proof of Compliance (PoC), which can be used instead of Proof of Sustainability (PoS) in the event that the fuel in question is also used by the fuel supplier for compliance towards the requirements under the Renewable Energy Directive. If the PoS is not available, it is recommended to always follow this PoC template to avoid issues with fuel eligibility under FuelEU and the EU ETS.

Illustration of certification flow and how PoC (brown document) can substitute the need for PoS (blue document) (source: Report on Marine Fuels Certification Procedures to support implementation of FuelEU Maritime)

Additionally, this report outlines procedures for certifying renewable and low-carbon marine fuels in line with FuelEU Maritime and the EU ETS. Overall, it provides practical instructions for fuel suppliers and shipping companies regarding the required documentation, sustainability certification, and traceability.

Certification of actual methane slip values
Until international standards are available, the FuelEU and EU ETS regulations currently only allow for the use of default methane slip values by engine type. Although the IMO guidelines for measuring methane slip from LNG engines were adopted at MEPC 83 in April, the guidelines lack:

• procedures for on-board monitoring of emissions (performance of after-treatment systems),
• methods to ensure that values remain stable over time (due to engine modifications), and
• standardized test cycles.

Following the above, the European Commission is working on interim guidelines to allow certification of actual values based on the IMO protocol. The guidelines are expected to be available in the second half of 2025.

FuelEU report submission enabled in Thetis – DNV is ready to receive FuelEU partial reports
When there is a change in company (e.g. due to sale of the vessel), a verified FuelEU report shall be recorded in the FuelEU database within one month after the change of company.

As of 18 June, the FuelEU database, which is part of the Thetis platform, has been updated to support FuelEU Maritime partial reports. Consequently, the FuelEU Maritime service under Fleet Status on Veracity has been adjusted to receive and process FuelEU partial reports from customers. Companies may now request the FuelEU partial report verification from our customer portal.

On 24 June 2025, EMSA and DG MOVE hosted a webinar on FuelEU, presenting a high-level overview of the FuelEU report and compliance balance modules in Thetis. We encourage our customers to view the recording for further insights.

Clarifications on implementation

Use of flexibility mechanisms
It is important to note that the use of pooling will not always result in a ship compliance balance of zero. A compliance surplus available after pooling can be banked for future use, while a deficit will trigger a penalty payment. Both borrowing and pooling come with limitations however – for example, borrowing is not permitted after pooling has been applied. The figure on the next page focuses on illustrating the key limitations and options available.