Italy lifts MACSE energy storage auction premium cap to €27,000/MWh

Italy's energy regulator, Arera, has raised the maximum premium for MACSE energy storage auctions to €27,000 per qualified MWh per year, up from a previous cap of €22,000. The decision, formalized in Resolution 332/2026 on September 24, reflects higher benchmark investment costs and is effective for the 2029 delivery year.

The benchmark investment cost for energy storage projects has been updated from €125,000 to €150,500 per MWh, a move that acknowledges rising project development and technology expenses. The new cap directly influences the economics of storage projects, potentially making them more attractive to investors but also introducing new considerations for developers.

Developers bidding in the MACSE auction must now adapt their strategies to the higher cap, balancing the security of a fixed premium against potential merchant revenues. According to Arera, the weighted average cost of capital (WACC) has been set at 8.2% as of August 31, providing a new reference for financial modeling and return expectations.

To participate in the upcoming auction, developers are required to provide a pre-auction guarantee equal to 10% of the investment amount, or €2,700 per qualified MWh, by October 20. The price-setting phase for the auction is scheduled for November 24, though the final mechanism remains to be determined by Terna, the Italian grid operator.

The revised premium cap is expected to increase investment attractiveness for energy storage in Italy, aligning incentives with the realities of higher capital costs. However, the adjustment also introduces risks: developers must carefully balance fixed premiums against fluctuating merchant market revenues, and increased thresholds could deter less-capitalized participants.

For the European and Latin American sectors, the Italian move signals a broader trend of rising costs and evolving regulatory frameworks in energy storage, with implications for cross-border investment and technology suppliers. The new premium cap may also influence how other European markets structure their own storage incentive mechanisms, as project economics become increasingly sensitive to regulatory parameters.