European Union – October 31, 2026 -- The EU Agency for the Cooperation of Energy Regulators (ACER) has approved amended implementation frameworks for the PICASSO and MARI electricity balancing platforms. It adopted Decisions 12/2026 and 13/2026 and added three prequalification options for balancing service providers (BSPs).
ACER received both proposals from all electricity transmission system operators (TSOs) on 18 December 2025. PICASSO coordinates cross-border exchanges of automatically activated balancing energy. MARI coordinates manually activated balancing energy. Both platforms draw on frequency restoration reserves.
ACER adds three prequalification routes for balancing providers
ACER introduced activation testing, ex-post verification and a fast-track process. Ex-post verification and the fast-track process give faster and easier market access than activation testing, because services are monitored during operation instead of tested upfront. TSOs may choose any or all three options, subject to approval by their national regulatory authority.
Harmonised requirements cover switching, termination and data exchange
ACER added requirements for switching, re-prequalification, termination of prequalification and data exchange. Some requirements remain at national level because experience with harmonised prequalification is limited. Further harmonisation is expected as TSOs gain experience.
TSOs must run stakeholder surveys every two years
Every two years, TSOs will survey stakeholders to identify where BSP terms and conditions still differ between countries. They will then draft a common proposal for further harmonisation and consult on it publicly.
Smaller participants get a simplified entry process
ACER simplified prequalification for smaller participants. Existing processes were designed around large conventional generators. The change aims to create a level playing field and improve liquidity.
TSOs have six months to file national proposals
TSOs must submit a proposal to their national regulatory authority within six months to align national terms and conditions with the new requirements. Once approved, they will have 24 months to implement the harmonised prequalification process.