Italy's transmission system operator Terna has confirmed that the main capacity market auction for the 2028 delivery period will be held on 21 December 2026, starting at 10:00. Applications opened on 20 October 2026 with a deadline of 3 November 2026 at 12:00; technical documentation and specific guarantees are due by 23 November, and participation deposits by 14 December.
BESS capacity recognised cut by up to 47.5%
The most significant parameter for storage developers is that the call includes cuts of up to 47.5% in the capacity recognised for new battery energy storage systems. Italy's scheme remunerates available capacity to guarantee security of supply, so the de-rating factor directly determines how much revenue a battery can lock in per megawatt of installed power for the delivery period.
A de-rating of that magnitude changes project economics: developers must size revenue stacks around a smaller firm-capacity payment and rely more heavily on wholesale, ancillary and tolling revenues. It also raises the bar for battery duration and availability guarantees, since the recognised capacity reflects what the system can be counted on to deliver during stressed hours rather than its nameplate rating.
Spain's framework is in place, the auctions are not
Spain approved its capacity market framework through Order TED/966/2026, published on 17 September 2026 in the Boletín Oficial del Estado. The norm establishes the regulatory architecture, but it still must be translated into the auctions that will define contracting conditions for sector companies. Spain continues to await the first calls of its capacity mechanism, lagging Portugal and Italy in converting framework into bankable revenue.
Diverging instruments, shared driver
The three markets illustrate how differently member states are pursuing the same objective. Portugal awards grid access rights for storage projects; Italy remunerates available capacity; Spain has legislated a mechanism but has not yet opened it. All are responding to the growing need for flexibility, firmness and renewable energy integration in European power systems.
What developers should watch
For Italy, the decisive variables are the final de-rating curves applied to new BESS, the auction clearing price and how much capacity is contested. For Spain, the timing of the first auction call and the eligibility conditions for storage will determine whether 2027 project timelines hold. For Portugal, the outcome of the 1,050 MVA grid reservation procedure will show whether access rights alone can attract investment without a capacity payment.
Source: Energía Estratégica
This article was assisted by AI analysis. Please refer to the original source for official information.