Blog The Twin Transition: Code, Carbon and Compliance

The green and digital transitions are increasingly navigating shared waters. The twin transition captures the interdependence between decarbonisation and digitalisation: digital technologies enable the green transition, while sustainability objectives increasingly reshape the development and deployment of digital technologies. In regulation, this relationship goes beyond replacing analogue reporting with digital systems. Data is increasingly fueling compliance itself, the information through which environmental obligations are monitored, verified and translated into regulatory consequences.

By Kelsey Pailman, PhD researcher and MSCA Fellow at the Groningen Centre of Energy Law and Sustainability.

Maritime decarbonisation brings this relationship into sharp focus. Shipping accounts for approximately 3% of global greenhouse gas (GHG) emissions (International Maritime Organization [IMO], 2020), while ship traffic to and from European Economic Area ports accounts for approximately 11% of transport-related CO₂ emissions and 3–4% of total EU CO₂ emissions (European Parliament & Council of the European Union, 2023). In response, the European Union (EU) and IMO have developed decarbonisation measures supported by distinct digital compliance systems.

At international level, the IMO’s Data Collection System (DCS) collects ships’ fuel-consumption data. At EU level, the Monitoring, Reporting and Verification (MRV) System supports the EU Emissions Trading System (EU ETS), while the FuelEU Maritime Regulation establishes the FuelEU Database for monitoring and reporting. As these systems collect and process related information for different regulatory purposes, what role can digitalisation play in fostering regulatory cohesiveness across maritime decarbonisation frameworks?

Against this background, this blog examines the implications of digital compliance systems for regulatory cohesiveness in maritime decarbonisation, tracing the issue from the FuelEU Database and procedural overlap within the EU, to questions of data quality and, ultimately, EU-IMO coordination.

From emissions data to legal compliance

The FuelEU Maritime Regulation illustrates the legal significance of digital compliance infrastructure. Companies monitor information on energy used on board and relevant emission factors, which is subsequently reported and independently verified (European Parliament & Council of the European Union, 2023, arts. 7, 15).

Central to this process is the FuelEU Database, which records verification activities, compliance balances, penalties and documents of compliance (art. 19). Commission Implementing Regulation (EU) 2026/394 further specifies its operation, including reporting, verification and the recording of compliance information. The database is therefore more than a repository: its data form part of the process through which compliance is established and regulatory consequences follow. As digital technologies increasingly support emissions monitoring and compliance (Khabir et al., 2025), the accuracy, verification and use of data across regulatory processes become legal compliance concerns.

Digitalisation and regulatory cohesiveness

The significance of digitalisation becomes clearer where regulatory regimes rely upon overlapping compliance processes. Guo and Wang (2026) describe “procedural overlap” arising from separate reporting, verification and registry systems, even where regimes rely upon related operational information.

The FuelEU Maritime Regulation does not operate in a digital vacuum. Ships already report emissions information under the EU MRV framework, which supports the EU ETS. Furthermore, for example, information on fuel consumption already reported under the EU MRV framework may also be relevant to FuelEU Maritime compliance calculations. Recitals 50 and 55 of the FuelEU Maritime Regulation envisage building on existing MRV arrangements, illustrating how shared reporting infrastructure can reduce duplication without merging the distinct obligations under FuelEU Maritime and the EU ETS (European Parliament & Council of the European Union, 2023, recitals 50, 55).

This provides an example of regulatory cohesiveness at the compliance level. Previous work examined cohesiveness between EU legislative instruments, including reporting arrangements supporting compliance (Pailman, 2025). The interaction between the FuelEU Database and EU MRV system demonstrates how aligning reporting requirements can reduce duplication and streamline compliance.

Khabir et al. (2025) similarly identify incompatible technologies and data-management systems as obstacles to coordination, emphasising interoperability and standardisation. Although FuelEU Maritime and the EU ETS perform different functions, they can rely on overlapping information, creating opportunities to reduce procedural overlap through shared data and infrastructure.

When data quality becomes a legal question

Reducing procedural overlap is not simply a technical exercise. It depends on the quality of the data used for compliance, including their accuracy, completeness, consistency and reliability. Freiter and Pache (2025) identify these concerns, alongside integration and standardisation, as challenges for digital emissions reporting, particularly where information originates from different systems or is affected by measurement or manual errors.

These issues acquire legal significance when data are used to determine compliance balances or financial liabilities. For example, an error in reported fuel consumption could affect the calculation of a ship’s FuelEU compliance balance. Where the same underlying data support multiple regulatory processes, such errors may have wider consequences. Although reliance on common data can reduce reporting duplication, it may also amplify the effects of inaccuracies across compliance determinations.

Nor does technical compatibility mean that data generated under one regime satisfy the methodology or verification requirements of another. Regulatory cohesiveness therefore requires more than technical interoperability: data must also be sufficiently reliable and appropriately verified to satisfy the requirements of the regulatory framework in which they are used.

From EU to global cohesiveness

Cohesiveness becomes more complex internationally. The IMO DCS operates alongside EU reporting systems, creating potential overlap where schemes require different data or methodologies.

This brings digitalisation into the broader question of regulatory cohesiveness between regional and international measures (Pailman, 2025). Guo and Wang (2026) identify differences in reporting objects, accounting boundaries and verification arrangements, while pointing towards alignment of data fields and recognition of verification results as possible coordination mechanisms.

This exposes an important distinction between technical interoperability and legal recognition. Data capable of moving between systems do not automatically satisfy the legal requirements of the receiving regime. Digitalisation can therefore facilitate regulatory cohesiveness, but cannot establish legal recognition by itself. Law must determine what information is recognised, how it must be verified and what regulatory consequences may follow.

Code, carbon and compliance

Digital systems are becoming embedded in the legal processes through which maritime emissions are monitored, verified and translated into regulatory consequences. The FuelEU Database, EU MRV System and IMO DCS show how digitalisation can support regulatory cohesiveness by reducing procedural overlap and enabling greater coordination. Yet this depends on the quality and verification of the underlying data and whether the same information can appropriately support different regulatory processes. Digitalisation can facilitate regulatory cohesiveness, but cannot create it alone. Code can connect the systems; law must determine what the connected data mean for compliance.