Slovenia has opened its wholesale electricity trading market to Nord Pool and Croatia’s CROPEX, creating new competition for incumbent BSP SouthPool. The change could affect trading services, market-access costs and operational risk management across Southeast Europe. The Multi-NEMO Arrangement has been operational since October 21, allowing three nominated electricity-market operators to provide day-ahead trading in the same Slovenian bidding zone under Europe’s integrated market-coupling framework. It adds competition between service providers without splitting wholesale price formation: all three take part in the common European day-ahead coupling process.
Traders, suppliers, industrial consumers and power generators can reassess their exchange memberships, clearing arrangements, collateral requirements and trading infrastructure. The operators will compete for customers through their platforms, membership terms, fees and related services. Market access is therefore becoming a competitive service rather than an activity tied exclusively to a national electricity exchange.
Three exchanges serve one bidding zone
Slovenia’s transmission system operator, ELES, confirmed on October 23 that the arrangement had been implemented after extensive regulatory, technical and contractual coordination. The work involved the Slovenian Energy Agency, BSP SouthPool, CROPEX, Nord Pool and participants in European market coupling. Nord Pool, owned by pan-European exchange operator Euronext, began trading Slovenian day-ahead electricity on October 21 for delivery on October 22, extending its reach to 17 European markets.
CROPEX, which has operated in Croatia for more than a decade, entered Slovenia at the same time. Its services give existing and new members access to both Croatian and Slovenian bidding zones. Before the reform, BSP SouthPool was the established provider for Slovenia’s organised day-ahead market, and participants seeking access to auction liquidity principally relied on its infrastructure and membership arrangements.
The new arrangement gives participants a choice of service providers while preserving access to the European Single Day-Ahead Coupling (SDAC) mechanism. Under SDAC, bids submitted through different nominated exchanges are brought together in a common market-coupling calculation. Participants can use competing exchange operators without creating separate national wholesale price-setting systems.
Competition between exchanges does not automatically reduce the wholesale electricity price paid by Slovenian consumers. It may, however, affect the cost and quality of trading services, operational arrangements and access to multiple national markets. The commercial consequences therefore extend beyond the addition of two trading platforms.
Fees, collateral and services become areas of competition
Participation in organised electricity markets involves costs beyond the purchase price of power. Companies need exchange memberships, trading accounts, collateral arrangements, information-technology interfaces and systems for managing physical and financial settlement. They also incur costs for compliance, market reporting, risk controls and links between exchange transactions and internal trading systems.
The reform gives the exchanges scope to compete over these services. A trader already using CROPEX in Croatia could assess whether accessing Slovenia through the same provider reduces additional administrative or technical requirements. Companies active across several European markets could likewise consider Nord Pool’s broader geographical coverage and technology infrastructure.
BSP SouthPool retains its established position in Slovenia and is connected to wider regional electricity-market cooperation through ADEX, involving Slovenia, Hungary and Serbia. The market now offers several models for regional access, but savings are not assured. Traders need to compare membership fees, transaction charges, clearing relationships, collateral treatment and operational requirements to determine whether consolidating activity with one provider would reduce costs.
Collateral can be particularly significant because electricity-trading companies often need substantial financial resources to support their exchange positions. More efficient collateral management through clearing arrangements may reduce the liquidity tied up in market participation. However, Slovenia’s Multi-NEMO reform does not create a common collateral pool across all three exchanges, so any savings depend on each participant’s clearing and contractual structures. Such differences can have commercial importance for companies with constrained working capital.
Euronext develops its energy-market business
Nord Pool’s entry into Slovenia is part of Euronext’s Innovate for Growth 2027 strategy, which aims to expand the group’s energy-market activities and geographical reach. The strategy combines physical electricity trading with the development of derivatives and clearing services. Euronext introduced Euronext Nord Pool Power Futures earlier in 2026 and plans to extend its derivatives offering to further European markets, starting with Germany in April 2027.
The strategy seeks to build a broader electricity-market infrastructure business linking physical transactions, risk management and financial trading. It could eventually give market participants opportunities to simplify access to related physical and financial products. The Slovenian launch does not, by itself, provide integrated futures contracts, shared collateral or new hedging instruments for Slovenian electricity.
Nord Pool can expand its physical-market customer relationships as Euronext develops complementary financial services. CROPEX is pursuing a different approach by extending an established regional exchange into a neighbouring national market. The contrast reflects a shift in exchange competition beyond domestic market operation towards regional customer acquisition and a wider range of trading services.
Trading resilience is also a financial risk issue
ELES also intends the reform to strengthen the resilience of electricity-market operations. The transmission operator said that having several exchanges in one bidding zone could reduce operational risks linked to market disruptions and decoupling events, which can have significant financial consequences for system operators. Interruptions to organised trading can expose suppliers and traders to unexpected procurement costs, settlement complications and short-term financial losses.
A company unable to execute planned transactions may have to adjust its positions through alternative arrangements, potentially at less favourable prices. Multiple exchange operators add trading-service options and may lessen dependence on a single provider, but they do not remove risks in shared infrastructure. A failure affecting the common European market-coupling algorithm could still disrupt trading across several exchanges at once.
The issue is therefore not only how many exchanges are available, but also the resilience of their trading interfaces, technical connections, clearing arrangements and contingency procedures. For larger energy-trading companies, exchange choice could increasingly form part of formal operational-risk management, alongside exposure to market prices, credit risk and liquidity requirements.
Slovenian reform follows regional infrastructure changes
The change came immediately after another restructuring of regional electricity-trading infrastructure. On October 20, ADEX Group launched a shared continuous intraday trading environment connecting the Slovenian, Hungarian and Serbian electricity markets. Under the arrangement, BSP took on operational responsibilities for ADEX’s continuous intraday markets, bringing activities associated with BSP SouthPool, HUPX and SEEPEX into a common technical environment.
The two initiatives take different approaches to market infrastructure. ADEX is consolidating operational processes across several national exchanges, while Slovenia’s Multi-NEMO Arrangement allows several competing operators to serve a single national bidding zone. Together, they point to a more complex electricity-trading landscape in Central and Southeast Europe, where exchanges can cooperate on technology and operations while competing for customers and revenues.
The changes are relevant to regional trading companies active in Serbia, Hungary, Croatia, Slovenia, Romania and the Western Balkans, particularly those managing portfolios across several wholesale markets. For Serbia, the immediate effect is increased competitive pressure on regional exchange services, rather than a direct change to SEEPEX’s domestic market rules. The Slovenian arrangement could nevertheless serve as a reference for assessing the longer-term economics of exchange membership, trading infrastructure and cross-border market access.
Intraday coupling is the next stage
The next step is to extend Slovenia’s Multi-NEMO Arrangement into the Single Intraday Coupling (SIDC) market, with implementation planned by the end of 2026. ELES and CROPEX have both confirmed that preparations are under way. Intraday access brings further operational considerations because companies must manage changing positions closer to physical delivery.
Technical connectivity, order execution, available trading limits and the reliability of market systems can become increasingly important to operational performance. The expansion would give exchange operators another area in which to compete for regional customers. Traders, in turn, will be able to assess whether a wider choice of exchanges justifies the additional technical and contractual complexity.
The longer-term effects will depend on how participants distribute transactions among providers, whether fee competition develops and whether clearing and collateral arrangements become more efficient. No verified post-launch data yet show a measurable redistribution of Slovenian trading volumes between BSP, CROPEX and Nord Pool. The coming months will therefore be important in assessing changes in market shares, trading costs and customer behaviour.
Slovenia’s experience could influence how other Southeast European markets assess the commercial organisation of their electricity exchanges. Competition is shifting from electricity transactions to the infrastructure used to execute, clear and manage them. For energy-trading companies, any advantage may come not from obtaining a different wholesale electricity price, but from reducing the financial and operational costs of accessing the same market.