PMB: European Power Exchanges (PCR)
Since 2012, Unicorn Systems has been a long-term technology partner of European Nominated Electricity Market Operators (NEMOs) within the Price Coupling of Regions (PCR) initiative. The cooperation focuses on the development, operation, and continuous evolution of the PMB application, one of the core components enabling the integrated European day-ahead electricity market and intraday auction market.
With production go-live in February 2014, PMB has been supporting market coupling across Europe for more than a decade — more than 4,500 completed market coupling sessions. In 2025, SDAC recorded no incidents of partial or full decoupling at all, and across the whole history of the coupling, no decoupling incident has ever been attributed to PMB.
Client's motivation and goals
The Price Coupling of Regions (PCR) initiative was established to enable an efficient, harmonised European day-ahead electricity market — calculating electricity prices and allocating cross-border capacities uniformly and simultaneously across all participating regions.
NEMOs needed a reliable, distributed integration layer that would let market operators, the price coupling algorithm, and surrounding IT systems work together seamlessly, while the market itself kept growing in scale and complexity. Key goals of the cooperation:
- Enable simultaneous, harmonised price calculation and capacity allocation across all participating regions
- Provide a reliable, distributed integration layer connecting NEMOs and their Local Trading Systems, the EUPHEMIA algorithm and surrounding systems
- Improve market liquidity and enable efficient cross-border electricity trade
- Optimise overall economic welfare across the coupled market
- Increase transparency of prices and power flows across Europe
Our solution
Behind every kilowatt-hour traded on Europe’s day-ahead market (SDAC) is a simple chain: market participants want to sell tomorrow’s output; another market participant wants to buy it. Neither trade directly — orders go through traders, producers and suppliers to a nominated electricity market operator (NEMO) in each country.
Every day at noon, all order books close simultaneously across Europe in NEMOs´ local trading systems. PMB then takes over: it collects the anonymised order books from all NEMOs together with the cross-border transmission capacities provided by TSOs and feeds them into the EUPHEMIA algorithm.
What looks like a single central computation is in fact multiple parallel ones — currently eight. An independent PMB instance runs at each power exchange that co-owns the PCR solution, each running its own EUPHEMIA calculation of the same pan-European optimisation problem. The solutions are compared, the best one becomes the common European result, and every NEMO verifies and confirms it.
Within minutes, results travel back the same way — from PMB to the NEMOs, and from the NEMOs to market participants — so market participants immediately know which of their orders were accepted and at what price. The result: one coordinated European price instead of dozens of isolated national auctions, and electricity flowing from where it’s cheapest to where it’s needed most.
Technology and architecture
PMB is a distributed application deployed across multiple NEMO locations and interconnected into a single operational ecosystem. The application is based on web technologies, with secure communication implemented via web services over HTTPS. PMB supports both day-ahead and intraday market processes and has been continuously extended to reflect regulatory, operational, and market-driven changes.
PMB’s technology roadmap reflects Unicorn’s commitment to continuous modernisation. In recent years, Unicorn Systems has focused on improving security, performance, maintainability, and user experience. Starting with PMB 13, a major GUI modernisation was initiated: the original server-side interface was gradually replaced with a modern single-page application built on REST APIs, improving usability, scalability, and performance while enabling faster future development.
Additional initiatives include extended performance and business monitoring, improved message processing, and preparation for future upgrades of core technologies such as Java, Spring Framework and application servers — alongside enhanced security measures, including penetration testing and data protection mechanisms.
Project timeline
Project results
More than a decade after go-live, PMB remains one of the most reliable pillars of Europe’s electricity market infrastructure — and it continues to scale as the market itself grows and evolves.
Looking ahead, PMB’s roadmap continues to track the market’s evolution: geographical extension of coupling to new regions (including the prospective inclusion of Energy Community countries in SDAC and SIDC), and the transition from ATC/NTC to Flow-Based capacity calculation in intraday markets.
Market coupling sessions completed since February 2014
Average time to first solution after the 2025 move to 15-minute market products (within a 30-minute window)
Traded on the European day-ahead market (SDAC) in 2025
Added value
Proven reliability
More than 4,500 completed market coupling sessions since 2014, with zero decoupling incidents ever attributed to PMB — including a perfect record across all of 2025.
Efficient cross-border trade
Implicit capacity allocation and coordinated, simultaneous price formation improve market liquidity and optimise welfare across the whole coupled region.
Price transparency
A single, coordinated European price replaces dozens of isolated national auctions, increasing transparency of prices and power flows.
Continuous modernisation
A modern single-page, REST-API based GUI (from PMB 13 onward) plus ongoing security hardening and performance monitoring keep PMB technically current.
Ready for what's next
Already supporting 15-minute market products (live since September 2025) and built on a modular architecture ready for further market coupling expansion.
About Client
The PCR initiative is driven by eight European power exchanges — EPEX SPOT, GME, HEnEx, Nord Pool EMCO, OMIE, OPCOM, OTE and TGE — in cooperation with Nominated Electricity Market Operators (NEMOs). NEMOs, together, are responsible for organising electricity markets and enabling efficient cross-border trading in line with European regulations under Commission Regulation (EU) 2015/1222 of 24 July 2015 establishing a guideline on capacity allocation and congestion management.
Through coordinated governance structures and close cooperation with TSOs and European institutions, NEMOs play a key role in the Single Day-Ahead Coupling (SDAC) and Single Intraday Coupling (SIDC) processes.
Acting as PCR SC Chairman
Vice-Chairman of the Board
OTE, a.s.
