Interconnector capacity is becoming a compliance consideration for electricity traders seeking to apply actual-emissions treatment under the EU Carbon Border Adjustment Mechanism (CBAM). Transmission rights and associated scheduling records can support whether imported volumes correspond to generation from a specifically identified eligible installation. The documentation focus extends beyond enabling cross-border commercial transactions between electricity markets.
Owning cross-border capacity does not, by itself, establish eligibility for actual-emissions treatment. Traders are required to maintain an auditable link between electricity produced, capacity allocated, and volumes nominated for import into the EU. This linkage is intended to connect the imported quantity to the eligible installation used for the claim.
Annex IV requirements for cross-border deliveries
Annex IV(5) includes requirements tied to connection to the EU transmission system or evidence that physical network congestion did not occur along the relevant route at the time of export. Firm nominations must also be made against allocated interconnection capacity by responsible transmission system operators (TSOs) in the country of origin, destination and any transit countries. These nomination obligations apply across the relevant cross-border path.
The nominations must correspond to the installation’s generation over intervals of no longer than one hour. The requirements apply cumulatively, meaning that purchasing a cross-border capacity right cannot replace other evidence needed to support an actual-emissions claim. Recordkeeping therefore needs to cover both capacity allocation and nomination-related proof.
Preparing records begins before electricity is delivered. Depending on the border and applicable market rules, transmission capacity may be obtained through daily, monthly or longer-term auctions. Traders need to identify the capacity holder, delivery period, relevant nominations, accepted amendments and final schedules.
The independent power producer’s generation records should be linked to accepted schedules using consistent timestamps and quantity units. Where capacity rights are resold or transferred, documentation must reflect the actual transaction and comply with applicable capacity-allocation rules. The aim is to align generation data with the schedule position used for import.
Serbia–Hungary: multiple parties in the evidence chain
The Serbia–Hungary border illustrates how many parties can contribute to the evidence chain. A Serbian electricity producer, a local balancing party, an EMS-related scheduling process, an EU import trader and an interface with MAVIR may all be involved even though they operate as separate entities.
Contracts need to define responsibility for collecting confirmations from each relevant system. They also need to specify how rejected, amended or otherwise changed nominations will be handled. A generation forecast provided to a trader does not constitute the same evidence as a final nomination accepted by the relevant TSO.
Responsibility allocation affects whether records can demonstrate a relationship between actual plant generation and the electricity schedule used for import. Missing or inconsistent confirmations can undermine documentation needed to support claimed emissions treatment. This requirement places emphasis on confirmation flows across systems involved in scheduling.
Montenegro–Italy: CGES–Terna interconnector conditions
The Montenegro–Italy corridor operates under different network conditions because electricity can be transmitted through the undersea CGES–Terna interconnection. Traders need to establish how market zones, allocated transmission rights and nomination requirements interact with dispatch at the generating installation in Montenegro.
The physical interconnector provides an export route, but its existence does not mean every element of the route between the generating plant and the EU border satisfies CBAM requirements. Cable availability and absence of congestion across the relevant network route are treated as separate considerations for compliance evidence.
As a result, evidence of interconnector access alone may not establish compliance. Traders are expected to retain relevant allocation and scheduling records and assess them against conditions applicable to the specific electricity delivery. The documentation requirement therefore extends beyond confirming access to a transmission path.
Portfolio aggregation and installation-level attribution
Portfolio aggregation creates additional documentation challenges for traders. Trading desks may offset purchases from several generating installations against a single physical import position to improve commercial netting efficiency.
The importer still needs to demonstrate which portion of final imported volume is attributable to each installation for which actual-emissions treatment is claimed. Portfolio-level reconciliation cannot replace installation-specific attribution required by applicable rules.
Information systems should prevent assigning the same nominated megawatt-hour to multiple claims. They should also distinguish between cancelled, amended and superseded schedules so that compliance records reflect the final accepted position rather than an earlier version.
Status of proposed EU changes on physical-network constraints
An EU legislative proposal would remove or revise some existing physical-network constraints related to evidence collection. As of October 2026, this reform remains a proposal rather than an enacted change allowing traders to discontinue congestion and nomination evidence collection.
Until legal requirements change, maintaining records at the current standard remains necessary. Contracts can include provisions allowing administrative requirements to be adjusted if future legislation changes what evidence is needed to qualify imported electricity for actual-emissions treatment.
Transmission-capacity teams and CBAM compliance teams are expected to work from shared records covering commercial positions, allocations, nominations and generation volumes. The economic assessment of an interconnector involves more than auction fees and congestion rents because missing nomination confirmations can create carbon-cost exposure exceeding the original capacity fee.