The Energy Agency of the Republic of Serbia, AERS, is consulting until Sept. 30 on new rules covering supplier switching, collective supplier switching and aggregator switching for electricity customers with full-supply contracts. The changes are procedural, but they affect how customers can change the company responsible for monetising flexible consumption or distributed energy assets.
Serbia’s electricity Market Code already recognises aggregators within the market framework. Under the market setup, EMS allows an aggregator to submit a single balancing bid for its aggregation group, while eligible balancing-service providers can include generators, aggregators, storage operators and final customers, subject to technical qualification.
Aggregator switching as a separate service relationship
An aggregator’s product is not electricity supply itself. It combines flexible demand, generation or other controllable resources from multiple customers and offers the resulting portfolio into electricity markets.
Creating a defined mechanism for changing aggregator arrangements begins to separate aggregation from the traditional supplier relationship. For industrial consumers, the framework could create competition over who manages their flexibility.
In practice, a factory can continue buying power from one supplier while another specialist company manages flexible loads such as pumps, compressors, heating and cooling equipment capable of temporarily altering consumption. The commercial question shifts from who supplies electricity to who can obtain the highest value from flexibility inside the facility.
If multiple aggregators compete for customer portfolios, customers can compare revenue-sharing arrangements, optimisation services and contractual terms. The same approach also supports a model where aggregation does not require owning generation assets.
Portfolio building and conditions for exit
An aggregator can build a portfolio by contracting with electricity consumers and controlling agreed parts of their demand. Hundreds of smaller resources can then be combined into one market-facing asset.
For Serbian industry, unused operational flexibility could become an additional revenue stream. For energy companies, aggregation can create a customer-acquisition route in which existing suppliers add aggregation to electricity contracts and independent firms specialise in demand response, industrial optimisation or virtual power plants.
Technology companies can also participate by supplying forecasting, telemetry and automated control systems that support aggregation operations. In this context, switching rules become commercially significant because customers need the ability to leave an aggregator if flexibility contracts otherwise become difficult to exit.
Industrial consumers may be reluctant to grant third parties operational access to equipment unless contractual exit procedures, data responsibilities and switching arrangements are clearly defined. Standardised switching is intended to reduce some of that friction and potentially increase competition between aggregators for customer portfolios.
ADEX integration targets common intraday trading limits
Power traders active across Serbia, Hungary and Slovenia are preparing for a common intraday trading environment under ADEX. Under the integration plan, continuous intraday markets operated through SEEPEX, HUPX and BSP SouthPool are due to move into a common M7 trading environment with launch planned for October 2026.
European Commodity Clearing (ECC) plans to replace existing market-specific trading limits with a single ADEX trading limit covering participating markets. Market participants will still need admission to each market they want to trade, while physical settlement, financial settlement, margining, products and reporting remain market-specific.
The reform therefore does not create one fully pooled clearing system, but it makes trading-limit management common across markets. A regional trading desk could manage available limit across Serbia, Hungary and Slovenia through one ADEX framework instead of maintaining separate market-specific limits.
The development also highlights collateral and treasury management as constraints on trading execution. ECC has told participants to coordinate with their clearing banks before migration because existing limits will not transfer automatically.
Romania increases financial guarantees for grid capacity allocation
Romania is turning access to scarce electricity-grid capacity into a more capital-intensive part of energy development as connection capacity becomes a balance-sheet issue. Transmission operator Transelectrica has launched infrastructure for allocating available grid capacity through competitive procedures, while regulator ANRE has increased financial guarantees required from developers.
For the 2026 allocation process, applicants must provide a guarantee of €20,000 per MW of requested capacity. A project requesting 100 MW would therefore need a participation guarantee of €2 million to enter the allocation process.
The platform accepts capacity applications, validates financial guarantees and prepares eligible projects for auction processing. The first 2026 application round ran from July 1 to July 14, with the objective of allocating scarce network capacity to projects with sufficient financial commitment rather than allowing speculative applications to occupy the connection queue.
ANRE has also tightened other parts of the connection regime. For qualifying projects, the financial guarantee associated with securing a connection approval increased from 5% to 20% of the connection tariff excluding VAT.
Developers seeking establishment authorisations face an additional guarantee of €30/kW of installed capacity subject to applicable regulatory conditions. The changes affect project financing timing because developers may need additional bank guarantees, credit lines or equity commitments earlier in the development cycle.
Croatia shortens balancing reserve products into four-hour blocks
Croatia has shortened the time commitment required to sell balancing capacity as transmission operator HOPS launched a new balancing platform on Sept. 15. The launch came with revised procurement rules for aFRR and mFRR balancing capacity and energy.
The main procurement change moves from offering reserve capacity for an entire day to allowing providers to bid into six four-hour blocks through day-ahead procurement. This structure is intended to make balancing capacity more compatible with flexible electricity demand patterns.
An industrial site may be able to guarantee flexibility from midday to 1600 hours but not throughout an entire day. An EV fleet may have controllable charging demand overnight but limited availability during daytime operations, while commercial buildings may have flexibility during occupancy periods.
The resource still needs HOPS qualification and contractual requirements before it can target specific periods when flexibility is available. HOPS has also changed balancing-energy bidding so bids can be submitted for individual Market Time Units and modified until 25 minutes before the relevant MTU begins.
Bids can be submitted via a graphical interface or machine-to-machine connectivity. As gate closure approaches real time and products become more granular, HOPS’ platform design requires aggregators and balancing-service providers to use software capable of forecasting asset availability and updating positions automatically.
Croatia prepares for European balancing system connections in 2027
The new platform is also part of Croatia’s preparation for connection to European balancing systems. HOPS expects connections for aFRR via PICASSO and mFRR via MARI during 2027.
The immediate market impact remains domestic through easier slicing of balancing capacity into periods matching availability from new flexibility providers. That creates potential opportunities for aggregators, industrial consumers, EV fleets and automated trading platforms as balancing supply expands beyond conventional reserve commitments.
The European Commission proposes data-centre performance standards affecting flexibility participation
The European Commission on Sept. 21 proposed a common EU rating system for data centres and opened consultation on possible minimum performance standards with legislation planned for 2027. The policy is being developed alongside efforts to expand computing infrastructure while managing its effect on electricity networks as the EU aims to roughly triple data-centre capacity by 2035.
The policy focus includes whether data centres should receive large firm grid connections or become more active participants in power-system flexibility. Data centres have traditionally been treated as highly reliable baseload consumers because computing services cannot simply shut down when grid constraints occur.
The Commission notes that not all data-centre electricity consumption is necessarily equally inflexible. Some computing workloads can potentially be shifted in time or geographically, cooling systems contain thermal flexibility, backup electricity infrastructure can provide additional controllability under carefully managed conditions, and facilities can coordinate on-site generation and electricity procurement with other energy systems.
The Commission also emphasises reuse of waste heat from data-centre cooling systems where suitable district-heating or industrial demand exists nearby. This links digital infrastructure with power-to-heat and sector coupling trends in which site selection depends not only on fibre connectivity and electricity supply but also on whether nearby energy systems can use waste heat.
The Commission argues that sustainable and flexible data centres able to adjust consumption to grid conditions can lower system costs, improve grid stability and help integrate renewable electricity. It also states that future data-centre electricity contracts may price both megawatt-hours consumed and megawatts agreed not to consume when the power system needs them most.