This section addresses common questions about EnExGroup: the Hellenic Energy Exchange (HEnEx) and the EnΕx Clearing House Single Member (EnExClear). It explains our role, operations, and contributions to the energy ecosystem. For press and general inquiries, please contact our team at communication.team@enexgroup.gr.
1. About HEnEx and EnExClear
HEnEx (Hellenic Energy Exchange) is an organized marketplace where wholesale energy and energy related products, such as electricity and natural gas, are offered in Greece. It provides a safe and reliable environment for companies to trade energy. HEnEx enables the formation of fair prices and connects Greece’s energy market with the rest of Europe.
EnExClear (EnEx Clearing House) acts as the safety net for all energy trades on HEnEx. It ensures the payment and completion of every energy transaction, so that market participants do not need to worry about others failing to meet their obligations. EnExClear does this by being the intermediary between buyers and sellers, handling payments and securities, and keeping emergency funds ready to protect the market, if problems arise.
The two companies are compensated by charging fees that are proportional to the volume of energy traded and cleared in HEnEx markets. They also generate revenue from annual membership fees paid by trading and clearing members. It is important to note that their revenues are not affected by the prices at which energy is traded in HEnEx markets.
HEnEx and EnExClear operate under strict regulatory oversight. Their fees are cost-reflective and cover the operation of secure and transparent markets. These fees are benchmarked against other European energy exchanges and applied under regulatory supervision to guarantee fairness, proportionality, and financial sustainability. For more information, please visit our website: Fees - EnExGroup.
2. Market Operations & Participants
HEnEx operates power, gas, and environmental markets. In the power sector, traders buy and sell electricity close to delivery in the Spot Markets, while in the Derivatives Market participants can lock in prices for future delivery periods, protecting themselves against sudden price fluctuations. For gas, HEnEx currently offers spot products with near-term delivery, while assessing the potential introduction of futures products.
All Spot Market trades are securely managed and finalized by EnExClear, whereas ATHEXClear is responsible for clearing and settling transactions in the Derivatives Market.
In addition, HEnEx operates the PPA Platform and continuously explores the further expansion of its activities into the Environmental Markets, such as the Guarantees of Origin (GOs).
All Spot Market trades are securely managed and finalized by EnExClear, whereas ATHEXClear is responsible for clearing and settling transactions in the Derivatives Market.
In addition, HEnEx operates the PPA Platform and continuously explores the further expansion of its activities into the Environmental Markets, such as the Guarantees of Origin (GOs).
Eligibility depends on the market or platform. In the Spot Markets, participation is limited to licensed energy companies and self-supplied consumers. In the Derivatives Market, eligible participants include licensed energy companies, investment firms, and banks. Access to the PPA Platform is open to a broader group, including energy companies, investment firms, banks, and final consumers.
To become active in the Spot and Derivatives Markets, participants must register with us, certify their traders, and either work with a clearing member or act as one themselves. For more information, please visit our website: Become a Member - EnExGroup.
To become active in the Spot and Derivatives Markets, participants must register with us, certify their traders, and either work with a clearing member or act as one themselves. For more information, please visit our website: Become a Member - EnExGroup.
3. Price Formation & Transparency
In HEnEx markets, prices are formed through the interaction of supply and demand. In the Electricity Day-Ahead Market, sellers and buyers submit their offers for electricity for the following day. Using the European algorithm called EUPHEMIA, these offers are matched across different countries to ensure the best economic outcome. The EUPHEMIA algorithm sets the Market Clearing Prices (MCPs) per region, the prices at which supply meets demand, and schedules optimal cross‑border electricity flows.
This process is transparent and adheres to European market rules, promoting a level playing field and reflecting market conditions.
This process is transparent and adheres to European market rules, promoting a level playing field and reflecting market conditions.
Key drivers include demand patterns (such as weather conditions and economic activity), the availability of generation units and interconnectors, renewable output, fuel and carbon costs, and market competition. For example, during temperature extremes, electricity prices tend to be higher than when temperatures are close to the average. Also, gas-fired plants often determine the marginal electricity price, and consequently, spikes in gas prices can influence electricity prices. This link remains strong even as the grid increasingly relies on renewable energy, because gas-fired plants are still essential for providing backup power when renewable sources are weak.
No, HEnEx provides the marketplace. Prices are determined by market forces such as supply, demand, and competition, in a fully transparent and regulated environment.
All participants trade anonymously under the same rules and standardized procedures that are publicly available here to maintain consistency. HEnEx records and monitors every transaction to keep the market running smoothly. EnExClear acts as the central counterparty, clearing and settling all spot market transactions, and removing counterparty risk.
HEnEx and EnExClear are supervised by national and European authorities. To further support transparency, HEnEx publishes detailed market data online, giving all stakeholders, including the general public, access to important market information. Το access market data, please visit our website: Publications - EnExGroup.
HEnEx and EnExClear are supervised by national and European authorities. To further support transparency, HEnEx publishes detailed market data online, giving all stakeholders, including the general public, access to important market information. Το access market data, please visit our website: Publications - EnExGroup.
4. Risk Management & Derivatives
Derivatives are financial instruments that allow market participants to lock in electricity prices for future delivery periods. They allow buyers and sellers to protect themselves against significant price fluctuations, making it easier to plan ahead.
In the Spot Market, energy is traded for short-term delivery (up to three days ahead), and prices reflect the near-real-time balance of supply and demand. The Derivatives Market includes financial contracts for future delivery periods, helping participants hedge against the risk of sudden price fluctuations. At the same time, it enables them to plan their business activities more effectively, along with the costs and revenues arising from energy transactions. For more information about our Derivatives Market, please visit our website: Derivatives - EnExGroup.
5. Strategic Role & Energy Transition
EnExGroup supports Greece’s shift to cleaner energy and Europe’s climate goals by providing market tools that integrate renewable energy, support flexibility, and enable clean power contracting.
● The continuous intraday market (XBID) and Intraday Auctions (IDAs) are designed to accommodate the intermittent and unpredictable nature of renewable energy, providing opportunities to adjust their positions closer to real time and thus ensuring a smoother integration into the market.
● By breaking down electricity trading into 15-minute intervals, the alignment of production and consumption improves, enhancing market flexibility. In turn, this makes it easier to accommodate fluctuating renewable generation.
● The Demand Response mechanism allows consumers to adjust their electricity usage, for instance during peak demand times. This helps reduce strain on the grid and manage demand more efficiently.
● EnExGroup runs the dedicated PPA Platform, launched in 2024, that provides a marketplace to facilitate bilateral renewable power purchase agreements.
● The continuous intraday market (XBID) and Intraday Auctions (IDAs) are designed to accommodate the intermittent and unpredictable nature of renewable energy, providing opportunities to adjust their positions closer to real time and thus ensuring a smoother integration into the market.
● By breaking down electricity trading into 15-minute intervals, the alignment of production and consumption improves, enhancing market flexibility. In turn, this makes it easier to accommodate fluctuating renewable generation.
● The Demand Response mechanism allows consumers to adjust their electricity usage, for instance during peak demand times. This helps reduce strain on the grid and manage demand more efficiently.
● EnExGroup runs the dedicated PPA Platform, launched in 2024, that provides a marketplace to facilitate bilateral renewable power purchase agreements.
The PPA Platform is an online marketplace created by HEnEx that connects renewable energy sellers and buyers. By providing a standard contract that simplifies negotiations, it helps businesses sign long-term clean power agreements and invest in green energy. You can find more information about the PPA Platform on our website: PPA Platform - EnExGroup.
By ensuring liquid and competitive markets, promoting cross-border electricity trading, and helping balance supply and demand efficiently.
6. Public Interest & Access
HEnEx provides transparent and non-discriminatory energy trading under a single set of rules and procedures, while EnExClear acts as the central counterparty that guarantees and settles those trades and manages counterparty risk. Together they deliver reliable price discovery and market integrity, foster competition and liquidity, and give suppliers the tools to hedge price risk. This supports the integration of renewable generation, strengthens system resilience, and aligns Greece with European market frameworks. For consumers and society, the result is more competitive pricing over time, a more reliable and cleaner energy system, and a stronger foundation for long-term investment and sustainability.
All key data is published on the EnExGroup website: Homepage - EnExGroup.
Please email at communication.team@enexgroup.gr or visit our media center.
Hellenic Energy Exchange S.A.
E-mail : info@enexgroup.gr
Tel : (+30) 210 33 66 400
Fax : (+30) 210 33 66 875