Slovenia has opened its wholesale electricity trading market to competing exchange operators, allowing Nord Pool and Croatia’s CROPEX to compete with incumbent BSP SouthPool. The Multi-NEMO Arrangement has been operational since October 21, giving three nominated electricity-market operators the right to offer day-ahead trading services in the same Slovenian bidding zone. The change introduces competition in exchange services while keeping Slovenia within Europe’s integrated market-coupling framework.
For traders, suppliers, industrial consumers and generators, the arrangement brings new options for organising exchange memberships, clearing, collateral and trading infrastructure. The operators compete over platforms, membership terms, fees and associated services, rather than through separate national wholesale price-setting systems. Market access itself is therefore becoming a competitive service rather than an activity tied exclusively to a national exchange.
Three operators serve Slovenia’s single bidding zone
Slovenian 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. All three operators participate in the common European day-ahead coupling process.
Nord Pool, owned by pan-European exchange operator Euronext, started trading Slovenian day-ahead electricity on October 21 for delivery on October 22. Its entry expanded its geographical presence to 17 European markets. CROPEX, which has operated in Croatia for more than a decade, entered Slovenia at the same time, allowing existing and new members to access both Croatian and Slovenian bidding zones through its services.
Before the reform, BSP SouthPool was the established provider for Slovenia’s organised day-ahead market, and participants seeking access to Slovenian auction liquidity primarily relied on its infrastructure and membership arrangements. The new system gives market participants a choice of service providers while retaining access to the European Single Day-Ahead Coupling (SDAC) mechanism. Under SDAC, bids submitted through different nominated exchanges are combined in the shared market-coupling calculation.
Competition among exchange operators does not automatically reduce the wholesale electricity price paid by Slovenian consumers. It can affect the cost and quality of trading services, operational arrangements and access to multiple national markets. The reform concerns the services through which participants enter the market, not the creation of separate Slovenian price-setting systems.
Fees, collateral and service arrangements become competitive factors
Participation in organised electricity markets involves costs beyond the electricity purchase price. Companies must maintain exchange memberships and trading accounts, arrange collateral, connect information-technology interfaces and manage physical and financial settlement. They also face costs for compliance, market reporting, risk controls and integration between exchange transactions and internal trading systems.
The new arrangement gives exchange operators scope to compete over these services. A trader already active on CROPEX in Croatia could assess whether accessing Slovenia through the same exchange reduces additional administrative or technical requirements. A company active in several European markets could similarly assess 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 resulting market offers several models for regional access. Traders must compare membership fees, transaction charges, clearing relationships, collateral treatment and operational requirements to determine whether consolidating activity with one provider produces savings.
Collateral is particularly relevant because electricity-trading companies often need substantial financial resources to support exchange positions. Clearing arrangements that allow collateral to be managed more efficiently may reduce the liquidity tied up in market participation. However, the Slovenian Multi-NEMO reform does not itself create a common collateral pool across the three exchanges; any potential savings depend on each participant’s clearing and contractual structures. Those differences can have commercial significance for companies with constrained working capital.
Euronext combines physical trading with financial-market development
Nord Pool’s Slovenian entry is part of Euronext’s Innovate for Growth 2027 strategy, which aims to expand the exchange group’s energy-market activities and geographical reach. The strategy brings together 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 other European markets, starting with Germany in April 2027.
The strategy aims to build a broader electricity-market infrastructure business spanning physical transactions, risk management and financial trading. For market participants, it could eventually offer opportunities to simplify access to related physical and financial products. The Slovenian launch does not itself provide integrated futures contracts, common collateral or new hedging instruments for Slovenian electricity.
Nord Pool’s physical-market entry extends its customer relationships as Euronext develops complementary financial services. CROPEX is pursuing a different expansion model by extending an established regional exchange into a neighbouring national market. The two approaches reflect competition for regional customers and a wider range of trading services, beyond the operation of domestic markets alone.
Operational resilience and regional market structures
ELES has also said the reform is intended to strengthen the resilience of electricity-market operations. The transmission operator said that allowing multiple exchanges in one bidding zone could reduce operational risks associated with market disruptions and decoupling events, which can carry significant financial consequences for system operators. Interruptions to organised electricity trading can expose suppliers and traders to unexpected procurement costs, settlement complications and short-term financial losses.
If a company cannot execute planned transactions, it may need to adjust its positions through other arrangements, potentially at less favourable prices. Multiple exchange operators provide additional trading-service options and may reduce reliance on a single provider. 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 operational issue therefore includes the resilience of trading interfaces, technical connections, clearing arrangements and contingency procedures, as well as the number of available exchanges. Larger energy-trading companies may increasingly include exchange selection in formal operational-risk management alongside price exposure, credit risk and liquidity requirements.
The Slovenian change followed another reorganisation of regional electricity-trading infrastructure. On October 20, the ADEX Group launched a shared continuous intraday trading environment linking the Slovenian, Hungarian and Serbian electricity markets. Under that 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 changes use different approaches: ADEX is consolidating operational processes across national exchanges, while Slovenia’s Multi-NEMO Arrangement allows competing operators to serve one national bidding zone. Together, they show exchanges cooperating on technology and operations while competing for customers and revenue. The changes are relevant to regional trading companies operating in Serbia, Hungary, Croatia, Slovenia, Romania and the Western Balkans, especially those managing portfolios across several wholesale markets.
For Serbia, the immediate effect is competitive pressure on regional exchange services, not a direct change to SEEPEX’s domestic market rules. The Slovenian arrangement may provide a reference point for assessing the longer-term economics of exchange membership, trading infrastructure and cross-border market access. Competition is extending beyond electricity transactions to the infrastructure used to execute, clear and manage them, with potential advantages for trading companies in the financial and operational costs of accessing the same market.
Intraday market access planned by the end of 2026
The next step is planned to extend Slovenia’s Multi-NEMO Arrangement to the Single Intraday Coupling (SIDC) market by the end of 2026. ELES and CROPEX have both confirmed that preparations for the expansion are under way. Intraday access adds 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 will be able to assess whether a wider choice of exchanges justifies additional technical and contractual complexity.
The longer-term effects will depend on how participants allocate transactions between 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 provide information on changes in market shares, trading costs and customer behaviour, while Slovenia’s experience could influence how other Southeast European markets assess the commercial organisation of their electricity exchanges.