Serbia’s electricity market is entering a more volatile and increasingly investable phase, as renewable-energy growth, negative prices, battery storage and CBAM requirements begin to interact rather than develop as separate policy and market trends.
SEEPEX introduced negative electricity prices in May 2026, bringing its minimum price limits closer to European market practice and providing generators, suppliers and storage developers with a clearer signal during periods of excess supply. Market liquidity has also increased, with SEEPEX reporting record monthly day-ahead trading volumes in May and June. At the same time, preparations continued for a common ADEX intraday continuous trading environment covering Serbia, Hungary and Slovenia.
These developments are changing the way renewable projects need to be evaluated. The key question is no longer simply whether the average wholesale electricity price is high enough to support a project. A solar plant can encounter very low or negative prices during midday hours, while evening scarcity increases the value of flexible capacity. Similarly, a wind project can generate substantial volumes during periods of congestion or weak market prices.
Battery storage can improve the commercial profile of renewable generation, but its interaction with CBAM introduces an additional layer of complexity. Current rules do not automatically treat renewable electricity shifted through storage as though it had been generated during the later discharge hour.
This creates two distinct optimisation challenges. The first is familiar to power-market participants: maximising generation value through accurate forecasting, balancing, intraday trading and storage. The second is increasingly important for EU-facing projects: preserving the evidence required to support an installation-specific export claim.
The optimal hour for wholesale electricity arbitrage may therefore not be the optimal hour for a low-carbon export product if the required contract structure, nomination or network evidence cannot be established for that particular transaction.
Serbia’s auction-backed renewable pipeline makes the issue increasingly relevant. Ten projects with a combined capacity of 645 MW were selected in the second renewable auction round, while the government has said that more than 1 GW of battery capacity is under development.
As larger volumes of intermittent generation enter the system, the commercial infrastructure will need to evolve toward more granular forecasting, improved settlement data and source-specific allocation. These capabilities will become particularly important when large amounts of solar and wind generation enter the market simultaneously.
CBAM adds another distinction between electricity sold domestically and electricity imported into the EU under the mechanism. A Serbian generator selling electricity on the domestic market can monetise energy, balancing services and environmental attributes through domestic contracts. A generator targeting EU import value must additionally consider the identity of the authorised CBAM declarant, the structure of the physical PPA, the evidence supporting cross-border delivery and the treatment of volumes that do not satisfy the actual-emissions requirements.
For this reason, batteries should initially be financed on the basis of revenues that can already be demonstrated, including arbitrage, imbalance reduction, reserve or flexibility services where available, and improved PPA shaping. Any CBAM-related value attributed to storage-mediated electricity should be treated as a separate legal and methodological workstream.
Lenders and investors should avoid incorporating unproven carbon-related upside into the fixed revenue case simply because a battery is charged from a renewable-energy facility.
The emergence of negative prices reinforces this approach. Negative pricing increases the commercial value of flexible demand, storage and sophisticated curtailment strategies, but it also makes annual renewable-energy balances less representative of actual commercial performance.
A project may generate sufficient renewable electricity over an entire year while selling, purchasing or replacing electricity during the specific hours that matter for a particular cross-border transaction. As the electricity market becomes increasingly hourly, the evidence architecture must become hourly as well.
For EPS, independent power producers, aggregators and trading companies, these developments point toward a more segmented electricity-product market. One product is conventional electricity priced against the relevant market hub and delivered under standard wholesale terms. A second can incorporate Guarantees of Origin or other environmental attributes. A third is an installation-specific transaction structured to support a particular CBAM emissions methodology.
The same generator may participate in all three markets, but these products should not be combined into a single, undefined promise of green electricity.
Serbia’s energy transition will therefore be determined by more than the number of renewable megawatts installed. Increasingly, competitive advantage will depend on flexibility, market access and data quality. Projects capable of accurately forecasting, nominating, reconciling and proving their electricity deliveries will be better positioned to capture value from both domestic market volatility and growing EU demand for low-carbon electricity.
Supported by CBAM.Clarion.Engineer