Slovenia has opened its wholesale electricity market to competing exchange operators, with Nord Pool and Croatia’s CROPEX now challenging incumbent BSP SouthPool. The Multi-NEMO Arrangement, operational since October 21, allows three nominated electricity-market operators to offer day-ahead trading in the same Slovenian bidding zone. The change introduces competition among service providers while keeping Slovenia within the integrated European market-coupling framework.
All three operators take part in the common European day-ahead coupling process and compete for customers through their trading platforms, membership arrangements, fees and related services. The reform does not split Slovenia’s wholesale electricity price formation. For traders, suppliers, industrial consumers and generators, it creates an opportunity to reassess exchange membership, clearing, collateral and trading infrastructure.
Three exchange operators serve Slovenia’s 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. The change also marks a broader commercial shift, as access to the market is no longer tied exclusively to a national electricity exchange.
Nord Pool, owned by pan-European exchange operator Euronext, began trading Slovenian day-ahead electricity on October 21 for delivery on October 22. The launch expanded Nord Pool’s 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 principally relied on its infrastructure and membership arrangements. The new system offers 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 a common market-coupling calculation, rather than being used to create separate national wholesale price-setting systems.
Competition between exchanges does not automatically reduce the wholesale electricity price paid by Slovenian consumers. It may affect the cost and quality of trading services, operational arrangements and access to several national markets. For exchange operators, the competition is therefore over the services surrounding market participation as well as the trading platforms themselves.
Fees, collateral and customer services become competitive factors
Participation in organised electricity markets carries costs beyond the purchase price of electricity. Companies must maintain exchange memberships, trading accounts, collateral arrangements and information-technology interfaces, as well as systems to manage physical and financial settlement. Compliance, market reporting, risk controls and integration between exchange transactions and internal trading systems also add to the cost of market access.
The Slovenian change gives exchange operators scope to compete over those services. A trader already using CROPEX in Croatia could assess whether accessing Slovenia through the same exchange reduces additional administrative or technical requirements. Companies active in several European markets could likewise assess Nord Pool’s wider geographical coverage and technology infrastructure.
BSP SouthPool retains an established position in Slovenia and is linked to wider regional electricity-market cooperation through ADEX, involving Slovenia, Hungary and Serbia. Traders therefore face several models for regional market access. Any economic benefit must be assessed against membership fees, transaction charges, clearing relationships, collateral treatment and operational requirements, including whether consolidating activity with one provider would produce savings.
Collateral is a particularly relevant consideration because electricity-trading companies often need substantial financial resources to support exchange positions. If clearing arrangements allow collateral to be managed more efficiently, a company may reduce the liquidity tied up in market participation. However, the Slovenian Multi-NEMO reform does not itself create a common collateral pool across all three exchanges; potential savings depend on each participant’s clearing and contractual structures. These differences can be commercially significant for companies with constrained working capital.
Euronext and CROPEX pursue different expansion models
Nord Pool’s Slovenian entry 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 expand its derivatives offering to additional European markets, starting with Germany in April 2027.
The strategic objective is to build a broader electricity-market infrastructure business linking physical transactions, risk management and financial trading. For market participants, this could eventually create opportunities to simplify access to related physical and financial products. The Slovenian launch does not, by itself, provide integrated futures contracts, common collateral or new hedging instruments for Slovenian electricity.
Nord Pool’s physical-market customer relationships can expand while Euronext develops complementary financial services. CROPEX is pursuing a different model by extending an established regional exchange into a neighbouring national market. The contrast reflects competition moving beyond domestic exchange operations towards regional customer acquisition and a wider range of trading services.
Operational resilience is also a financial risk concern
ELES has said that the reform is intended in part to strengthen the resilience of electricity-market operations. In its view, allowing several exchanges to operate in one bidding zone could reduce operational risks associated with market disruptions and decoupling events, which may have significant financial consequences for system operators. Interruptions to organised trading can also expose suppliers and traders to unexpected procurement costs, settlement complications and short-term financial losses.
A company unable to execute planned transactions may need to adjust its positions through alternative arrangements, potentially at less favourable prices. Multiple exchange operators provide additional trading-service options and may reduce dependence on one provider. They do not remove risks tied to shared infrastructure: a failure affecting the common European market-coupling algorithm could still disrupt trading across several exchanges at once.
The operational question is therefore not only how many exchanges are available, but also how resilient their trading interfaces, technical connections, clearing arrangements and contingency procedures are. For larger energy-trading companies, exchange selection could increasingly form part of formal operational-risk management, alongside market-price exposure, credit risk and liquidity requirements.
Slovenia’s model follows a regional infrastructure change
The reform followed another change to regional electricity-trading infrastructure. On October 20, the 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 multiple competing exchange operators to serve one national bidding zone. Together, they reflect a regional trading landscape in which exchanges may 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 significance is competitive pressure on regional exchange services, rather than a direct change to SEEPEX’s domestic market rules. Slovenia’s arrangement may nevertheless serve as a reference for assessing the longer-term economics of exchange membership, trading infrastructure and cross-border market access.
Intraday access is the next planned expansion
The next stage 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 preparations for the expansion. Intraday trading brings additional 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. For exchange operators, the expansion would provide another area in which to compete for regional customers. Traders will be able to compare whether a wider choice of exchanges justifies additional technical and contractual complexity.
The longer-term effects will depend on how participants allocate 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 among BSP, CROPEX and Nord Pool. The coming months will be important for assessing any material 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 extending from electricity transactions to the infrastructure used to execute, clear and manage them. For trading companies, any resulting advantage may come from reducing the financial and operational costs of accessing the same market, rather than obtaining a different wholesale electricity price.