The manager of the Italian electricity system, Terna, has officially confirmed the date for the holding of the second auction of the long-term electricity storage capacity procurement mechanism (MACSE), following months of expectations in the sector. The tender, which had already been anticipated in regulatory terms by the authority ARERA at the end of March 2026, will take place on November 24, 2026, at 10:00 a.m. and will involve a total volume of 16 GWh.

The call for tenders is part of the development of MACSE, the Italian storage capacity scheme designed to facilitate the integration of renewable energy sources, strengthen the security of the electricity system, and improve grid efficiency.

A consolidated regulatory framework

The MACSE mechanism is based on Legislative Decree 210/21, which transposes the European electricity market package, as well as national energy system development regulations. Within this context, the regulatory authority ARERA issues opinions on the evolution of the system’s storage capacity needs, which serve as the basis for planning by the Ministry of Environment and Energy Security and for the operational design carried out by Terna.

In its March 2026 opinion, ARERA endorsed the proposed phased progression of storage capacity needs developed by Terna, a key step in planning through 2029.

16 GWh auction with delivery in 2029

The MACSE auction will allocate new storage capacity with a delivery horizon of 2029, mainly based on lithium-ion batteries and other non-reference technologies.

The total volume of 16 GWh will be distributed geographically within the following ranges:

• Central-South: 1–3 GWh
• South and Calabria: 3–11.5 GWh
• Sicily: 1–6 GWh
• Sardinia: 0.5–3 GWh

Source: MACSE.it- Linkedin

This distribution reflects the need to reinforce the grid in areas with high renewable energy penetration and structural constraints.

Timeline of the process

Terna has also detailed the full participation schedule for the auction:

• Admission applications: July 7 to July 27, 2026 (until 4:00 p.m.)
• Upload of documentation to the MACSE portal: until September 10, 2026
• Pre-auction guarantee deposit and formal declarations: until October 20, 2026
• Auction date: November 24, 2026, at 10:00 a.m.

Applications must be submitted exclusively through the official MACSE portal. For companies based outside the European Union, additional documentation will be required, including an affidavit in accordance with official templates.

The announcement confirms the operational rollout of the Italian electricity storage market, one of the first national schemes of its kind in Europe. Following the regulatory validation by ARERA and the regulatory framework approved by the Ministry, the publication of the auction date marks the effective start of the second competitive process under MACSE.