As of April 30th, 2025, the capacity of pending requests for the interconnection to the National Transmission Grid (“RTN”) for renewable energy plants was approximately 354.35 GW, of which almost half related to solar energy (152.98 GW), a significant percentage dedicated to the development of onshore (109.09 GW) and offshore (89.16 GW) wind projects, and the remaining share (3.12 GW) allocated to other less conventional sources[1].
The regions with the highest number of applications are those in central and southern Italy, particularly Puglia, Sicily, Sardinia, Basilicata, and Lazio.
We are well beyond the decarbonization targets set by the PNIEC, according to which Italy is required to install “just” 65 GW of new renewable capacity by 2030, which is only one-fifth of the capacity currently reserved on the grid.
However, a significant percentage of connection applications are still in an embryonic or almost embryonic stage. In fact:
for 59.47 GW, the relevant STMGs are still to be accepted;
for 153.07 GW, the STMGs have been accepted (but the network works project is not yet under evaluation);
for 72.63 GW, the network works projects are still being evaluated by the operator;
for 57.96 GW, the relevant projects have received clearance (i.e., they have been “validated” or “approved”);
for 8.11 GW, the STMD has been issued.
If the addends are changed and only projects that have been approved and for which the STMD has been issued are taken into account, the above figure falls to 66.07 GW, in line with the PNIEC targets but well below the capacity currently reserved.
Given their early stage, it is likely that many of the initiatives for which network capacity has been reserved (and the related project has not yet been validated) will not be successful; as a result, there is a potential oversizing of network infrastructure.
In this context, in recent months, MASE and Terna have been working to develop strategies to avert potential risks of virtual grid congestion linked to the considerable number of connection requests related to these embryonic projects.
In order:
on March 14, Terna published its 2025 network development plan, dedicating a specific chapter to efficient territorial planning and connection measures;
as part of the conversion into law of the so-called Bollette Decree, which took place on April 24, MASE presented an amendment (later withdrawn) aimed at making significant changes to the rules governing connection procedures through the introduction of new methods for reserving network capacity and specific priority criteria;
on April 28, a rapid consultation process was launched for trade associations on the new rules proposed by MASE;
at the beginning of this month, the Minister stated that the regulations in question – which should have the same features as those (almost) introduced by the DL Bollette – will soon be regulated by an amendment or an ad hoc decree (based on recent statements by the Director General for Energy Markets and Infrastructure of the MASE, this measure should enter into force by the end of 2025).
Well, from a joint analysis of the above documentation and the information available to date, it would appear – except for offshore plants, which should be excluded from the objective scope of application of the regulation – that the regulatory framework governing connection to the RTN has been almost completely revolutionized compared to the current one.
The main features of this new framework that are relevant for current and future investments in the renewable energy sector are summarized here below.
Microzones
For defining connection solutions, there will be a transition from the current “individual case” management system to a system based on the design of “comprehensive” solutions.
In this context, the concept of “micro-zone” is being introduced, i.e., a sub-regional (and therefore sub-zonal) portion of the RTN, which, according to an initial mapping carried out by Terna, sees the emergence of 76 different micro-zones.
The new connection process therefore involves an analysis: (i) inter-microzone, assessing the capacity that can be accommodated in each microzone, taking into account the exchange constraints between micro.zones and the degree of congestion in that particular micro-zone; and (ii) intra-microzone, designing an overall connection solution for each microzone that can accommodate the capacity estimated on the basis of the inter-microzone analysis.
The data relating to each micro-zone will be available to operators via the TE.R.R.A. telematic portal managed by Terna and subject to quarterly updates depending on the progress of the projects that have been allocated network capacity.
The portal will therefore provide a snapshot of the maximum additional capacity from renewable sources and storage – apart from offshore plants – that can be allocated in each microzone.
Capacity allocation procedures
Based on the previous amendment, which was subsequently withdrawn:
the allocation of available network capacity and the related connection solutions should be issued through transparent and non-discriminatory procedures to be established by ARERA within 180 days of the entry into force of the new regulations;
for operators who, following competitive procedures, have been allocated network capacity and have already obtained the relevant permitting titles (PAS or Single Authorization), the relevant network capacity should be allocated on a definitive basis.
The current method of analyzing connection requests involves a sequential criterion for allocating connection solutions with one-to-one assessments conducted with operators for each request.
On the contrary, with the new provisions being introduced, it would appear that the operator will carry out an upstream assessment, defining an overall solution applicable to the relevant microzone, and will proceed with the allocation of network capacity not through individual procedures initiated at the request of the operators concerned, but through actual public procedures (which, in line with the obligation to connect third parties to the RTN, at least in theory, should not be “competitive”).
A significant advantage will be reserved for projects that have obtained authorization, for which the relevant capacity will be allocated definitively.
Projects in progress and STMGs already issued
As mentioned above, the principles, functional criteria, and operating procedures for allocating network capacity through the above-mentioned transparent procedures should be detailed by ARERA in an ad hoc measure to be issued within 180 days from the entry into force of the new legislative framework.
In this regard, one of the most significant changes, especially for initiatives that have already been launched or are in the start-up phase, is the provision whereby, as of the date of publication of the measure adopted by ARERA, connection solutions relating to renewable projects or storage facilities that are not authorized and are already issued but not validated by the network operator, will cease to be effective.
In a nutshell, looking at the current situation, if this rule were already in force and the ARERA measure already adopted, the procedures relating to approximately 202 GW of power would be null and void, forcing operators to take part in the above-mentioned transparent procedures to reserve the capacity necessary to carry out their development initiatives.
The innovations that MASE is about to introduce are clearly of considerable importance for current and future renewable project development initiatives.
In fact, if the provisions previously included and then withdrawn from the Bollette Decree were to be confirmed in their entirety:
it will become even more crucial to speed up and streamline the authorization procedures related to the development of renewables, given that, in essence, the projects that obtain the authorization title more quickly will be those that will be the first to obtain definitive network capacity, to the detriment of projects that are slow to get off the ground, which will see an increased risk of losing the capacity allocated in the context of the procedure launched by Terna in the event of definitive saturation of the relevant micro-zone;
it is likely that, in the coming months, there will be a real rush for approval for initiatives at a more advanced stage in order to try to prevent the risk of forfeiture of the STMG obtained;
it is equally likely that, if the absence of any safeguard clause for projects for which the STMG has already been accepted or the related network works project is currently being evaluated by the operator is confirmed, there will be multiple disputes by the operators concerned due to the sudden loss of their acquired right to the previously reserved network capacity. In this regard, it should be noted that the possible termination of the STMG should not be immediately consequent upon the entry into force of the regulation. It will be necessary to wait for the subsequent ARERA regulation (assuming that the regulation enters into force by the end of June, the subsequent ARERA regulation should be available by December 2025 – i.e., within 180 days).
It should be noted that these are merely preliminary considerations. In fact, to have a clear, complete, and comprehensive picture of the future new regulations, it will be necessary to wait for the entry into force of the legislation and the subsequent implementing measures of ARERA.
The practical implications of the new legislation will also need to be observed to assess whether it is actually suitable for ensuring efficient planning of the RTN infrastructure while protecting market players by preventing and not creating new bottlenecks.
[1] Data taken from Terna's econnextion platform.
