Gross scheduled electricity exchanges between the Western Balkans Six and neighbouring EU markets fell 17.8% in January–September 2026, while regional day-ahead trading expanded, the Energy Community Secretariat said in its third-quarter assessment. The figures show organised-market activity growing even as scheduled flows remained below 2025 levels, amid carbon-related costs for electricity transactions with the European Union.
Exchanges were 14.3% lower year on year in the third quarter, although they recovered 8.6% from the previous quarter. The assessment covers electricity trading in the quarter and compares the first nine months of 2026 with the corresponding period in 2025.
Day-ahead volumes on SEEPEX, MEPX, ALPEX and MEMO reached approximately 2.97 TWh in the third quarter, up 26.7% year on year. The increase across the four organised markets contrasted with lower scheduled exchanges between the region and neighbouring EU markets.
Carbon costs reshape trading margins
Across eight Western Balkan–EU electricity price pairs, absolute hourly price differences exceeded €20/MWh in 53.9% of third-quarter hours, compared with 21.7% a year earlier, the assessment found. Wider spreads may not translate into profitable cross-border trades when carbon obligations and delivery costs reduce the available commercial margin.
The European Commission set the third-quarter 2026 CBAM certificate price at €82.32 per tonne of CO₂, up from €75.28 in the second quarter. The actual cost of electricity imports also depends on the applicable emissions methodology, eligible deductions and other regulatory conditions.
Traders need to compare EU wholesale revenues with procurement costs, transmission charges, losses, balancing exposure and CBAM-related liabilities, according to the assessment. A price spread that previously supported cross-border arbitrage may no longer provide an attractive margin after those costs and obligations are included.
The report describes growing carbon-related costs as an additional consideration in electricity transactions between the Western Balkans and the EU. It also points to a potential structural discount for exporting markets with carbon-intensive generation mixes, or where low-carbon output does not meet requirements for recognition of actual emissions.
Export flows diverge by route
Scheduled electricity exports from Serbia to Hungary declined 21.6% despite a wider wholesale price spread between the two markets. Scheduled exports from Montenegro to Italy moved in the opposite direction, increasing approximately 80%.
The contrasting routes show that CBAM exposure does not determine commercial flows independently of other factors, the assessment said. Generation, demand, hydrology, trading positions, transmission capacity and contractual arrangements also influence exchanges.
Wholesale prices, transmission access and verified carbon characteristics are increasingly interconnected commercial variables. The assessment says Western Balkan generators may face a growing distinction between electricity that can be sold domestically or regionally and output that can economically reach EU customers.
For Serbia, Montenegro and the wider Western Balkans, the report identifies the challenge as preserving efficient electricity trade while adapting to carbon rules that can determine whether cross-border transactions are profitable. It cautions that the observed changes cannot be attributed exclusively to CBAM, since generation, demand, hydrology and available interconnection capacity also affect trading patterns.
