MACSE is back: Italy lines up 16 GWh storage auction for 2029

Italy’s energy regulator ARERA has issued a favorable opinion to the Ministry of the Environment and Energy Security (MASE) on grid operator Terna’s proposal to set a 16 GWh target for the MACSE storage capacity auction for 2029.

While endorsing the overall approach taken by the transmission system operator, ARERA has nonetheless stressed the importance of a prudent approach when defining the volumes actually put to auction, in order to account for the evolving market dynamics, in particular, any storage capacity that could come online or already be procured through the Capacity Market between the publication of the proposed timeline for storage capacity needs and the publication of the auction volumes.

The additional 16 GWh requirement is distributed across the relevant grid zones as follows, with minimum and maximum requirements in play:

• North and Central-North: 0 GWh
• Central-South: minimum 1 GWh – maximum 3 GWh
• South and Calabria: min. 3 GWh – max. 11.5 GWh
• Sicily: min. 1 GWh – max. 6 GWh
• Sardinia: min. 0.5 GWh – max. 3 GWh

ARERA explains that the minimum requirement represents the share of storage capacity that must be procured in each zone to guarantee a minimum level of renewable energy integration, while the maximum requirement represents the highest volume of storage the electricity system is prepared to procure in each zone.

Terna has modelled several trajectories for the rollout of storage capacity, based on different analyses of natural gas costs and storage development costs. For the next MACSE auctions, Italy’s TSO is working from an expected total requirement of 42 GWh by 2030.

“Given the 10 GWh already procured for the 2028 MACSE auction, this would imply an additional requirement of 32 GWh by 2030. Terna suggests procuring 50% of that additional requirement for 2029 — i.e. 16 GWh — deferring the precise determination of requirements for subsequent years to further assessments that can take into account the expected evolution of natural gas costs and storage development costs, as well as a precise estimate of the adequacy contribution in line with the derating coefficients that will be introduced for battery storage in the upcoming capacity market auctions,” states the document published by Arera [seven page PDF in Italian].

From pv magazine Italy.