Italy’s energy storage needs could reach 170 GWh by 2035

How much storage does Italy actually need?

The starting point is the country’s grid operator, Terna. In its most recent document on new storage capacity requirements to 2029, the scenarios vary significantly. Conservatively, the efficient sizing for 2030 is 42 ± 2 GWh, broadly in line with the national energy and climate plan (PNIEC) target. In the base case, Terna indicates around 104 GWh of storage by 2030, rising to approximately 134 GWh by 2035, including the 10 GWh already procured in the first auction.

The 42 GWh figure that many operators cite represents a cautious baseline focused primarily on system adequacy. The 104 GWh scenario shows what could happen when the benefits of avoided overgeneration, gas costs, the value of uncurtailed renewable energy, falling battery costs and the flexibility needs of an increasingly renewable electricity system are more fully accounted for.

If we look at storage only as reserve capacity, the market looks smaller. If we look at it as renewable integration infrastructure, the scale changes entirely.

A battery does not only serve to guarantee adequacy in critical hours. It absorbs renewable energy that would otherwise be wasted, reduces congestion, limits price cannibalization in solar hours, improves the profile of renewable assets, reduces gas use during evening ramp-ups, and makes new merchant investments more bankable.

So why does Terna also reference 42 GWh for 2030? Because Terna is probably proceeding in stages. The first MACSE auction, with delivery in 2028, allocated 10 GWh of capacity. For 2029, the Ministry of the Environment and Energy Security (MASE) and Terna approved a further 16 GWh. But if Terna’s base case already points to 104 GWh by 2030, the 26 GWh total across 2028 and 2029 is not the destination. It is the start of the cycle.

The central question is not whether storage will have room after the second MACSE. The question is how quickly that room will be recognized by regulatory mechanisms. When solar truly starts to accelerate, the risk will not be having too many batteries. The risk will be arriving short.

Terna’s 2025 “Italy Adequacy Report” confirms that installed wind and solar capacity reached 57 GW at end-2025, against a 2030 PNIEC target of 107 GW. In five years the system must make an enormous leap. The greater the share of non-programmable renewables, the more necessary it becomes to shift energy in time, reduce waste and stabilize the market.

FER X, finally approved, can transform a significant share of stalled projects into bankable investments, stabilizing revenues and improving financeability. But it does not eliminate the physical challenges of renewable integration – it makes them more urgent. If large volumes of solar capacity enter service simultaneously, the energy produced in solar hours will need to be absorbed, transported, valorized or curtailed. FER X is not an alternative to storage. It is one of the reasons storage will become increasingly necessary.

Cost dynamics point in the same direction. Batteries are becoming more competitive, bankable and scalable. If gas remains relevant in setting the marginal price and battery costs continue to fall, the economic value of uncurtailed renewable energy increases – and so does the efficient quantity of storage the system can absorb.

This is where the scenario of more than 100 GWh by 2030 becomes comprehensible: not because anyone wants to fill Italy with batteries, but because a system with more solar, more volatility, more potential congestion and more electrification will need far more capacity to shift energy from hours when it is worth little to hours when it is genuinely needed.

The race for storage in Italy has only just begun.

From pv magazine Italia