JUDGMENT NO. 156

YEAR 2026

ITALIAN REPUBLIC

IN THE NAME OF THE ITALIAN PEOPLE

THE CONSTITUTIONAL COURT

composed of:

President: Giovanni AMOROSO;

Judges: Francesco VIGANÒ, Luca ANTONINI, Stefano PETITTI, Angelo BUSCEMA, Emanuela NAVARRETTA, Maria Rosaria SAN GIORGIO, Filippo PATRONI GRIFFI, Marco D’ALBERTI, Antonella SCIARRONE ALIBRANDI, Maria Alessandra SANDULLI, Roberto Nicola CASSINELLI, Francesco Saverio MARINI,
has pronounced the following

JUDGMENT

in the proceedings concerning the constitutional legitimacy of Articles 1(2), (5), (7), and (8), and Article 3, as well as Annexes A, B, C, D, and E of Regional Law of the Autonomous Region of Sardinia No. 20 of December 5, 2024, entitled "Urgent measures for the identification of suitable and unsuitable areas and surfaces for the installation and promotion of renewable energy source (RES) plants and for the simplification of authorization procedures”; Article 5(1) and (2) of Decree-Law No. 63 of May 15, 2024 (Urgent provisions for agricultural, fishing, and aquaculture enterprises, as well as enterprises of national strategic interest), converted, with amendments, into Law No. 101 of July 12, 2024; and Article 2(2), first sentence, of Legislative Decree No. 190 of November 25, 2024, entitled "Regulation of administrative regimes for the production of energy from renewable sources, in implementation of Article 26(4) and (5), letters b) and d) of Law No. 118 of August 5, 2022”, brought by the Regional Administrative Court for Latium, Third Section, in the proceedings pending between Iberdrola Renovables Italia spa and the Ministry of the Environment and Energy Security and others, by means of the referral order of May 13, 2025, registered under No. 146 of the 2025 register of orders and published in the Official Gazette of the Republic, 1st Special Series, No. 35 of the year 2025.

Having regard to the appearances of Elettricità futura - Union of Italian Electricity Enterprises, Iberdrola Renovables Italia spa, and the Autonomous Region of Sardinia, as well as the intervention brief of the President of the Council of Ministers;

having heard Judge Rapporteur Angelo Buscema at the public hearing on July 7, 2026;

having heard counsel Carlo Comandè for Iberdrola Renovables Italia spa, Daniele Chiatante for Elettricità futura - Union of Italian Electricity Enterprises, Giovanni Parisi for the Autonomous Region of Sardinia, and State Attorney Giammario Rocchitta for the President of the Council of Ministers;

having deliberated in the chambers on July 7, 2026.

The Law in Brief

1.– By order of May 13, 2025, registered under No. 146 of the 2025 register of orders, the Regional Administrative Court for Latium, Third Section, raised questions as to the constitutional legitimacy of Articles 1(2), (5), (7), and (8), and Article 3, as well as Annexes A, B, C, D, and E of Regional Law of Sardinia No. 20 of December 5, 2024, entitled "Urgent measures for the identification of suitable and unsuitable areas and surfaces for the installation and promotion of renewable energy source (RES) plants and for the simplification of authorization procedures”, with reference to Articles 3, 9, 11, 41, 97, and 117(1), (2)(m) and (s), and (3) of the Constitution, also in relation to the principles expressed by Directive (EU) 2018/2001 of the European Parliament and of the Council of December 11, 2018, on the promotion of the use of energy from renewable sources, by Regulation (EU) 2021/1119 of the European Parliament and of the Council of June 30, 2021, establishing the framework for achieving climate neutrality and amending Regulations (EC) No. 401/2009 and (EU) 2018/1999 ("European Climate Law”), as well as with reference to Article 10 of Constitutional Law No. 3 of October 18, 2001 (Amendments to Title V of Part Two of the Constitution) and Articles 3 and 4 of Constitutional Law No. 3 of February 26, 1948 (Special Statute for Sardinia).

By the same order, challenges are also brought against Article 5(1) and (2) of Decree-Law No. 63 of May 15, 2024 (Urgent provisions for agricultural, fishing, and aquaculture enterprises, as well as enterprises of national strategic interest), converted, with amendments, into Law No. 101 of July 12, 2024, and Article 2(2), first sentence, of Legislative Decree No. 190 of November 25, 2024, entitled "Regulation of administrative regimes for the production of energy from renewable sources, in implementation of Article 26(4) and (5), letters b) and d) of Law No. 118 of August 5, 2022”, with reference to Articles 3, 9, 11, and 117(1) of the Constitution, also in relation to the principles expressed by Directive 2018/2001/EU and Regulation (EU) 2018/1999 of the European Parliament and of the Council of December 11, 2018, on the governance of the Energy Union and Climate Action, amending Directives 94/22/EC, 98/70/EC, 2009/31/EC, 2009/73/EC, 2010/31/EU, 2012/27/EU, and 2013/30/EU of the European Parliament and of the Council, Council Directives 2009/119/EC and (EU) 2015/652, and repealing Regulation (EU) No. 525/2013 of the European Parliament and of the Council, as amended by Directive (EU) 2023/2413 of the European Parliament and of the Council of October 18, 2023, amending Directive (EU) 2018/2001, Regulation (EU) 2018/1999, and Directive 98/70/EC as regards the promotion of energy from renewable sources and repealing Council Directive (EU) 2015/652, and by Regulation (EU) 2021/1119.

1.1.– The referring judge premised that they are seized of the decision on the appeal brought by Iberdrola Renovables Italia spa for the annulment of Articles 1, 3, and 7 of the Ministerial Decree of June 21, 2024 (Regulations for the identification of suitable surfaces and areas for the installation of renewable source plants), adopted by the Minister of the Environment and Energy Security in concert with the Ministers of Culture and of Agriculture, Food Sovereignty, and Forests, on the grounds that the aforesaid decree – together with the subsequent state and regional provisions – would cause immediate prejudice to the industrial initiatives of the aforesaid company.

1.2.– Concerning relevance, with reference to Regional Law of Sardinia No. 20 of 2024, the referring judge points out that among the projects submitted, three are located in the territory of Sardinia ("Benetutti Mercuria”, "Carbonia-Iglesias”, and "Prangili”) and that environmental impact assessment procedures have already been initiated for them, as they fall within areas classified as "unsuitable” by the regional map, and that the application of the combined provisions of Articles 1 and 3 of the aforesaid Sardinian law would entail an absolute prohibition on the construction of the plants and the supervening ineffectiveness of the authorization titles.

Still on the point of relevance, regarding Article 5(1) of Decree-Law No. 63 of 2024, as converted, which introduces a generalized and binding prohibition on the installation of photovoltaic plants with ground-mounted modules in zones classified as agricultural by urban planning schemes, the referring judge asserts that the application of the challenged provision would be unavoidable, since the prohibition in question directly affects a further agrivoltaic project of the same company, and the conditions for the applicability of the transitional regime provided for by paragraph 2 of the same article do not subsist.

1.3.– Regarding the non-manifestly unfounded nature of the questions, the Regional Administrative Court for Latium considers that the challenged provisions of Regional Law of Sardinia No. 20 of 2024 conflict with the principles established by the state legislator in Legislative Decree No. 199 of November 8, 2021, entitled "Implementation of Directive (EU) 2018/2001 of the European Parliament and of the Council of December 11, 2018, on the promotion of the use of energy from renewable sources” – now: "Implementation of Directive (EU) 2018/2001 of the European Parliament and of the Council of December 11, 2018, on the promotion of the use of energy from renewable sources, as amended by Directive (EU) 2023/2413 of the European Parliament and of the Council of October 18, 2023, amending Directive (EU) 2018/2001, Regulation (EU) 2018/1999, and Directive 98/70/EC as regards the promotion of energy from renewable sources and repealing Council Directive (EU) 2015/652” – in the exercise of legislative competence in the matter of "national production, transport, and distribution of energy” referred to in Article 117(3) of the Constitution and by fundamental rules of economic and social reform which are binding even upon regions with special autonomy, as well as with the provisions of the aforementioned Ministerial Decree of June 21, 2024.

Decarbonization objectives and the principle of the maximum dissemination of renewable energies expressed by Directive 2018/2001/EU and Regulation (EU) 2018/1999, as amended by Directive 2023/2413/EU and Regulation (EU) 2021/1119, would also be infringed, thereby violating Articles 11 and 117(1) of the Constitution.

The referring judge further states that the challenged regional regulation, by establishing the retroactive ineffectiveness of authorization titles already issued in the absence of safeguards for the legitimate expectations of operators, would violate the principles of reasonableness, proportionality, and sound administration referred to in Articles 3 and 97 of the Constitution.

Finally, conflict with Article 9 of the Constitution is alleged, since the unconditional sacrifice of energy supply from eco-friendly sources would infringe the very principle of sustainable development established for the protection of future generations, imposing the "tyranny” of the value of landscape conservation over the competing interest in ecological transition.

According to the referring judge, moreover, Article 1(8) of Regional Law of Sardinia No. 20 of 2024, where it establishes that "[r]efurbishment, complete reconstruction, and upgrading interventions [...] shall be permitted only if they do not entail an increase in the gross occupied surface area, nor, in the case of wind power plants, an increase in the total height of the plant”, would violate the principles of equality, legal certainty, and legitimate expectations, as well as the right to freedom of economic initiative referred to in Article 41 of the Constitution.

Article 3 of Regional Law of Sardinia No. 20 of 2024, by introducing an alternative procedure to overcome the prohibition on installing renewable energy source (RES) plants, which deviates from the ordinary functioning of the conference of services and significant silence provided for by state legislation on administrative proceedings (Article 29(2-ter) of Law No. 241 of August 7, 1990, entitled "New rules on administrative proceedings and the right of access to administrative documents”), would conflict with Article 117(2)(m) of the Constitution, which assigns exclusive legislative power to the State in the determination of the essential levels of performance concerning civil and social rights to be guaranteed throughout the national territory. Furthermore, by establishing a procedure different from that provided by the State even in areas subject to cultural or landscape protection (Articles 21 and 146 of Legislative Decree No. 42 of January 22, 2004, entitled "Code of Cultural Heritage and Landscape, pursuant to Article 10 of Law No. 137 of July 6, 2002”), this provision would also conflict with Article 117(2)(s) of the Constitution, which assigns the matter of "protection of the environment, ecosystem, and cultural heritage” to the exclusive legislative competence of the State.

1.4.– As to the non-manifestly unfounded nature of the questions concerning Article 5(1) of Decree-Law No. 63 of 2024, as converted, Articles 3, 9, and 117(1) of the Constitution would be violated, since, by providing for a generalized, abstract, and absolute prohibition on a purely urban planning basis – without any distinction regarding the actual productivity of the land (including degraded or abandoned agricultural areas) or the specific technologies employed (such as advanced agrivoltaic systems ensuring crop continuity) – the provision inflicts an intolerable blow upon the principles of proportionality and reasonableness.

The Regional Administrative Court for Latium points out that with the aforementioned provision the legislator carried out a rigid and aprioristic balancing in favor of the protection of agricultural land, precluding any concrete assessment by the administration and resulting in the total and unjustified sacrifice of private economic initiative, thereby violating Article 41 of the Constitution, and of global environmental protection linked to the reduction of greenhouse gases, thus also infringing Articles 9 and 117(1) of the Constitution.

The same challenges are also directed against paragraph 2 of Article 5, which lays down a safeguarding regulation presupposing the prohibition referred to in paragraph 1, as well as against Article 2(2), first sentence, of Legislative Decree No. 190 of 2024, where, in recalling compliance with the provisions of Article 20(1-bis) of Legislative Decree No. 199 of 2021, it reproduces the same prohibition referred to in the aforementioned Article 5(1) of Decree-Law No. 63 of 2024, as converted.

2.– The Autonomous Region of Sardinia entered an appearance in the proceedings, requesting that the questions of constitutional legitimacy raised by the Regional Administrative Court for Latium be declared inadmissible or, in any event, unfounded.

2.1.– As a preliminary matter, the regional defense objects to the inadmissibility of the questions due to a lack of relevance under various and concurrent profiles.

First of all, the questions would be inadmissible since no measure of the Autonomous Region of Sardinia was challenged in the main proceedings, nor any implementing act of the challenged Regional Law of Sardinia No. 20 of 2024, given that the subject matter of the introductory appeal brought by Iberdrola Renovables Italia spa is solely the Ministerial Decree of June 21, 2024. Consequently, the relevance of the questions raised regarding the regional law was framed in purely hypothetical terms.

2.2.– The questions would, in any event, be inadmissible due to their absolute generality and indeterminacy, since the Regional Administrative Court for Latium challenged an entire and complex web of provisions of Regional Law of Sardinia No. 20 of 2024, without clarifying which specific provision finds effective and concrete application in the main dispute.

The Autonomous Region of Sardinia adds that the projects of Iberdrola Renovables Italia spa exclusively concern wind and agrivoltaic plants, and this fact would render irrelevant the challenges directed against Annexes A, D, and E (relating to traditional, thermodynamic, or other types of photovoltaic plants), as well as those directed against Article 3 (concerning municipalities' applications) and Article 1(8) (relating solely to repowering or revamping interventions) of Regional Law of Sardinia No. 20 of 2024.

According to the regional defense, the referring judge limited themselves to formulating a vague assessment, omitting to indicate which criteria of unsuitability, among the many identified by the regional law, concretely affect the territories concerned by the industrial initiatives of the aforesaid company.

2.3.– On the merits, the Autonomous Region of Sardinia argues that all the questions raised are unfounded.

As to the violation of Articles 3, 9, 11, 41, 97, and 117 of the Constitution, as well as of EU and state interposed parameters regarding the maximum dissemination of renewable energies, the regional defense points out that the concept of an "unsuitable area”, outlined by Article 1(2)(b) of the Ministerial Decree of June 21, 2024, expressly defines such surfaces as "incompatible” with the installation of specific types of plants. Therefore, far from introducing an arbitrary prohibition, the Sardinian legislator faithfully conformed to the dictates of the interposed rule.

The challenged regional law qualifies – according to the regional defense – as a territorial governance and urban planning law, adopted in the exercise of the primary legislative power recognized to the Region by Article 3, letter f) of the special statute, the prerogatives of which are expressly safeguarded both by Article 49 of Legislative Decree No. 199 of 2021 and by Article 9 of the aforementioned Ministerial Decree of June 21, 2024.

Finally, regarding the challenges directed against the alleged retroactive effect of Regional Law of Sardinia No. 20 of 2024 on pending proceedings and on titles already issued (with feared harm to legitimate expectations and legal certainty), the questions would be unfounded by virtue of the general principle *tempus regit actum* which, in complex proceedings, translates into the principle *tempus regit actionem*, for which reason the *jus superveniens* is fully authorized to shape authorization proceedings not yet concluded.

3.– Iberdrola Renovables Italia spa, appellant party in the main proceedings, entered an appearance, insisting on the acceptance of the questions raised by the Regional Administrative Court for Latium.

4.– The President of the Council of Ministers, represented and defended by the State Attorney General's Office, also entered an appearance, arguing the inadmissibility and, in the alternative, the lack of foundation of the challenges.

4.1.– Regarding inadmissibility, the President of the Council of Ministers maintains that the challenges are formulated in a purely dubitative form and based on unproven factual elements. Indeed, no documentation was provided on how the prohibition on installing photovoltaic plants with ground-mounted modules concretely compromises the possibility of achieving the decarbonization targets agreed upon at the European level.

4.2.– On the merits, the questions would in any event be unfounded.

The State Attorney General maintains that the same reasons put forward in support of inadmissibility would, in any event, serve as the basis for dismissing the questions on the merits.

Indeed, there is no element suitable for demonstrating that the remaining modalities of utilizing agricultural land for solar energy production – through the use, for example, of advanced agrivoltaic systems – are such as to compromise the achievement of EU environmental protection and energy efficiency objectives. On the contrary, the regulations under examination would constitute the expression of a legitimate legislative choice aimed at balancing the needs of energy production with the protection of the agricultural destination of the land, also in light of the safeguarding mechanisms provided for by the European legal order.

The state defense thus recalls European Union principles on sustainable development, highlighting how the European Union itself pursues a balance between energy transition and the safeguarding of agricultural territory.

Such an objective implies the adoption of accurate territorial planning, accompanied by rigorous environmental assessments, as well as the use of compatible technologies, such as latest-generation agrivoltaics.

According to the State Attorney General, the referring judge omitted to consider that the maximum dissemination of renewable sources does not constitute an absolute value, as it can be balanced with other constitutionally relevant interests, according to a systemic approach already affirmed by the jurisprudence of this Court (reference is made to Judgment No. 85 of 2013).

In this perspective, Article 5(1) of Decree-Law No. 63 of 2024, as converted, would represent a legitimate legislative choice aimed at preventing the irreversible consumption of agricultural land and ensuring balanced territorial governance, without absolutely precluding the energy exploitation of agricultural areas.

Moreover, according to the State Attorney General, the prohibition introduced by Article 5(1) of Decree-Law No. 63 of 2024, as converted, does not constitute an absolute preclusion to the construction of energy production plants from renewable sources over a large part of the national territory, since it allows the use of advanced agrivoltaic systems suitable for preserving the continuity of agricultural and pastoral activities.

From a systemic perspective, the prohibition would not constitute an absolute and unreasonable preclusion, but rather implements the principle of proportionality, aimed at avoiding the irreversible and generalized sacrifice of agricultural land in the presence of less impactful technical alternatives, thus representing an essential constraint for policies of renewable energy source development characterized by balance and sustainability.

5.– Association Elettricità futura - Union of Italian Electricity Enterprises entered an appearance, pursuant to Article 3 of the Supplementary Norms for Proceedings before the Constitutional Court, as representative of the interests of enterprises operating in the national electricity supply chain, requesting the acceptance of the questions raised by the referring judge and the consequent declaration of constitutional illegitimacy of all the challenged provisions.

6.– The State Attorney General's Office, in the brief filed near the public hearing, maintains that the *jus superveniens* introduced by Article 2 of Decree-Law No. 175 of November 21, 2025 (Urgent measures concerning the Transition 5.0 Plan and the production of energy from renewable sources), converted, with amendments, into Law No. 15 of January 15, 2026, significantly modified the regulation of suitable areas for plants fueled by renewable energy sources (RES) by inserting Article 11-bis within Legislative Decree No. 190 of 2024. Therefore, the automatic transfer of judicial review to the new provision is to be excluded, given that the supervening norm introduces changes compared to the previous discipline: on the one hand, it establishes the full admissibility of agrivoltaic plants with elevated modules; on the other hand, it introduces entirely unprecedented elements, such as verified assessment requirements and the 80 percent threshold of sellable gross production.

The State Attorney concludes by insisting that the questions be declared unfounded and, in the alternative, that the case files be remitted to the referring judge in light of the changed legislative framework.

7.– The Autonomous Region of Sardinia also filed a brief insisting on the declaration of inadmissibility of the questions. On the merits and in the alternative, the regional defense notes that this Court's Judgment No. 184 of 2025 has already declared the constitutional illegitimacy of numerous provisions of the same Regional Law of Sardinia No. 20 of 2024. The state regulatory framework regarding RES has also radically changed as a result of the entry into force of Decree-Law No. 175 of 2025, as converted. This reform repealed Article 20 of Legislative Decree No. 199 of 2021, which governed the regions' power in identifying suitable areas and upon which the very Ministerial Decree of June 21, 2024, challenged in the main proceedings, rested.

The Region's defense concludes by recalling the consistent case law of this Court according to which, whenever the reference regulatory framework or the interposed parameters have undergone considerable modifications, the remittance of the case files to the judge a quo should be ordered.

The Law Considered

8.– The Regional Administrative Court for Latium, Third Section, by the order in the heading (reg. ord. No. 146 of 2025), questions the constitutional legitimacy of Articles 1(2), (5), (7), and (8), and Article 3, as well as the related Annexes A, B, C, D, and E of Regional Law of Sardinia No. 20 of 2024, with reference to Articles 3, 9, 11, 41, 97, and 117(1), (2)(m) and (s), and (3) of the Constitution, also in relation to the principles expressed by Directive 2018/2001/EU, Regulation (EU) 2021/1119, as well as with reference to Article 10 of Constitutional Law No. 3 of 2001 and Articles 3 and 4 of the Special Statute. The challenged regional provisions place limits and preclusions on the installation of RES plants.

The referring judge also questions the constitutional legitimacy of Article 5(1) and (2) of Decree-Law No. 63 of 2024, as converted, and Article 2(2), first sentence, of Legislative Decree No. 190 of 2024, with reference to Articles 3, 9, 11, and 117(1) of the Constitution, also in relation to the principles expressed by Directive 2018/2001/EU and Regulation (EU) 2018/1999, as amended by Directive 2023/2413/EU and Regulation (EU) 2021/1119.

Article 5(1) of Decree-Law No. 63 of 2024, as converted, inserted paragraph 1-bis into Article 20 of Legislative Decree No. 199 of 2021, which, in the text in force at the time of bringing the main proceedings, provided as follows: "[t]he installation of photovoltaic plants with ground-mounted modules in zones classified as agricultural by current urban planning schemes shall be permitted exclusively in the areas referred to in letters a), limited to interventions for the modification, refurbishment, upgrading, or complete reconstruction of plants already installed, provided they do not entail an increase in the occupied area, c), including quarries already subject to environmental restoration and those with a completed cultivation plan not yet restored, as well as closed or restored landfills or landfill lots, c-bis), c-bis.1), and c-ter), numbers 2) and 3) of paragraph 8 of this article. The first sentence shall not apply in the case of projects providing for photovoltaic plants with ground-mounted modules aimed at establishing a renewable energy community pursuant to Article 31 of this decree, nor in the case of projects implementing other investment measures of the National Recovery and Resilience Plan (NRRP), approved by ECOFIN Council Decision of July 13, 2021, as amended by ECOFIN Council Decision of December 8, 2023, and of the National Plan for Investments Complementary to the NRRP (PNC) referred to in Article 1 of Decree-Law No. 59 of May 6, 2021, converted, with amendments, into Law No. 101 of July 1, 2021, or of projects necessary for achieving the objectives of the NRRP”.

The subsequent paragraph 2 further establishes that "[a]rticle 20(1-bis), first sentence, of Legislative Decree No. 8 of November 2021, No. 199, introduced by paragraph 1 of this article, shall not apply to projects for which, as of the date of entry into force of this decree, at least one of the administrative procedures, including environmental assessment procedures, necessary to obtain the titles for the construction and operation of the plants and related connected works has been initiated, or at least one of the titles itself has been issued”.

Finally, the challenged Article 2(2), first sentence, of Legislative Decree No. 190 of 2024, prior to being amended by Decree-Law No. 175 of 2025, as converted, provided as follows: "[t]he interventions referred to in Article 1(1) shall be considered of public utility, urgent, and non-deferrable and may be located also in zones classified as agricultural by current urban planning schemes, in compliance with what is provided in Article 20(1-bis) of Legislative Decree No. 8 of November 2021, No. 199”.

9.– Prior to examining the challenges brought by the referral order, the inadmissibility of the questions concerning Annexes A, B, C, D, and E must be raised *ex officio*, brought with reference to Articles 3, 9, 11, 41, 97, and 117(1) and (3) of the Constitution, also in relation to the principles expressed by Directive 2018/2001/EU, Regulation (EU) 2021/1119, as well as Article 10 of Constitutional Law No. 3 of 2001 and Articles 3 and 4 of the Special Statute.

The referring judge challenges the entire set of Annexes, concerning the lists of unsuitable areas in relation to the various plants (photovoltaic and thermodynamic "A”, agrivoltaic "B”, wind "C”, biomass, landfill gas and biogas "D”, geothermal "E”), without formulating autonomous challenges for each of them and also omitting to identify – as would have been their burden in light of the consistent jurisprudence of this Court (ex plurimis, Judgment No. 218 of 2014, orders No. 227 of 2016 and No. 101 of 2015) – the individual norms, or parts thereof, the presence of which in the legal order would determine the alleged violation of the invoked constitutional parameters.

The set of challenged Annexes, in fact, comprises heterogeneous provisions, part of which has no bearing whatsoever on the grievances formulated – which are focused on the prohibition of installing RES plants on areas classified as unsuitable – and none of which addresses the discretionary choice of the Autonomous Region of Sardinia to identify the areas indicated in the aforesaid Annexes as "unsuitable”.

10.– Conversely, the exceptions of inadmissibility for lack of relevance formulated by the regional defense with reference to the further challenged regional and state statutory provisions must be dismissed.

As regards Regional Law of Sardinia No. 20 of 2024, it can be inferred from reading the referral order that three of the projects owned by Iberdrola Renovables Italia spa ("Benetutti Mercuria”, "Carbonia-Iglesias”, and "Prangili”) – located in the territory of Sardinia and for which environmental impact assessment procedures have already been initiated – fall within areas classified as "unsuitable” by the aforementioned regional law, and that the application of the combined provisions of Articles 1 and 3 thereof would entail an absolute prohibition on constructing the plants and the supervening ineffectiveness of the authorization titles. Therefore, the relevance of the questions concerning the provisions of Regional Law of Sardinia No. 20 of 2024 is sufficiently demonstrated.

As for Article 5(1) of Decree-Law No. 63 of 2024, as converted, which introduces throughout the national territory the prohibition on installing photovoltaic plants with ground-mounted modules in zones classified as agricultural by urban planning schemes, the relevance of the questions clearly emerges because the referring judge plausibly represents that the challenged prohibition would directly affect further agrivoltaic projects of the company, and the conditions for the applicability of the transitional regime provided for by paragraph 2 of the same article do not subsist.

11.– Likewise unfounded are the exceptions of inadmissibility, based on the generality of the challenges, formulated by the regional defense and the State Attorney General's Office.

The Regional Administrative Court for Latium, in fact, provides sufficient reasoning both for the questions concerning regional legislation and for the questions concerning state legislation regarding the installation of photovoltaic plants with ground-mounted modules in agricultural areas.

12.– Still as a preliminary matter, the *thema decidendum* of the questions raised regarding Regional Law of Sardinia No. 20 of 2024 must be circumscribed.

Indeed, although the order challenges – *ex aliis* – Articles 1(5) and 3 of Regional Law of Sardinia No. 20 of 2024, the challenges must be understood as referring solely to the first sentence of Article 1(5), where it provides that in areas qualified as unsuitable there is a prohibition on installing RES plants; and – as regards Article 3, solely to paragraphs 1, 2, 4, 5, and 6, where the specific procedure of application to the municipality to overcome the prohibition on installation in unsuitable areas is regulated.

13.– In order to examine the questions of constitutional legitimacy raised by the order indicated in the heading, it is first necessary to reconstruct the complex regulatory and jurisprudential framework concerning renewable energy source plants.

The recognition by the state legislator, in implementation of European Directive 2018/2001, of regional competence to identify by law suitable and unsuitable areas for the installation of RES plants (Article 20(4) of Legislative Decree No. 199 of 2021) has created "a functional arrangement to give prominence to regional autonomy” also in view of better landscape protection, with the clarification, however, that "unsuitability can never equate to an absolute and aprioristic prohibition” (Judgment No. 134 of 2025).

Legislative Decree No. 190 of 2024, the so-called consolidated text on RES administrative regimes, intervened to reorganize the complex regulation of the matter, reducing the number of administrative models to three (free activity, simplified authorization procedure, single authorization), for each of which a specific annex containing the description of the interventions determining its application has been prepared.

Lastly, Article 20 of Legislative Decree No. 199 of 2021 was repealed by Decree-Law No. 175 of 2025, as converted, which, in Article 2(1)(h), introduced a new regulation for identifying suitable areas by inserting Article 11-bis (Suitable areas on land) into Legislative Decree No. 190 of 2024.

Regions are therefore required to identify, by law, suitable areas for the installation of renewable source plants additional to those referred to in Article 11-bis(1) of Legislative Decree No. 190 of 2024, on the basis of the new regulation and, in particular, in compliance with the principles and criteria established by paragraph 4 and the objectives set by paragraph 5 of the same article (as provided by Article 11-bis(3)), and no longer in implementation of Article 20 of Legislative Decree No. 199 of 2021 and the Ministerial Decree of June 21, 2024.

14.– Still *in limine*, it must be noted that the entry into force of Decree-Law No. 175 of 2025, as converted, and the repeal of the challenged norm produce no effects on these constitutional legitimacy proceedings.

On this point, this Court has repeatedly highlighted that when the main proceedings concern the challenge of an act, the "repeal has no effects on the [...] constitutional proceedings, since, pursuant to the principle *tempus regit actum*, the referring judge is required to carry out the assessment [of the act they are called upon to review] in light of the discipline [...] in force at the time of its issuance” (Judgment No. 127 of 2026 and, in the same sense, Judgment No. 257 of 2017).

Moreover, "to render incidental questions admissible, it is sufficient that the challenged norm is applicable in the *judicium a quo*” (Judgment No. 46 of 2014).

Indeed, the present referring judge in the main proceedings is called upon to review the legitimacy of the Ministerial Decree of June 21, 2024, adopted in application of Article 20(1-bis) of Legislative Decree No. 199 of 2021, introduced by the challenged Article 5(1), so there is no doubt as to the persistence of the requirement of relevance.

Consequently, the conditions for a remittance of the case files do not arise on this profile, since "the review of the legitimacy of administrative acts is subject to the principle of *tempus regit actum* and must therefore be conducted on the basis of the rules in force at the time of their adoption” (Order No. 30 of 2024; in the same sense, among many, Judgments No. 172 of 2024, No. 180 of 2022, No. 227 of 2021, No. 170, No. 109, and No. 7 of 2019, No. 240 of 2018, No. 281, No. 245, No. 203, No. 49, and No. 30 of 2016).

15.– Within the described evolution of the regulatory framework, this Court has been repeatedly called upon to rule on the constitutional legitimacy of various legislative provisions adopted by the Autonomous Region of Sardinia regarding RES plants, over a considerably short span of time.

More precisely, by Judgment No. 28 of 2025 this Court declared constitutionally illegitimate Article 3 of Regional Law of Sardinia No. 5 of July 3, 2024 (Urgent measures for the safeguarding of the landscape and of landscape and environmental heritage), which had ordered the suspension of all applications and authorized projects pending the adoption of the regional law identifying suitable areas.

By subsequent Judgment No. 184 of 2025, constitutional illegitimacy was declared, insofar as relevant here, against Articles 1(2), first sentence, limited to the words ", or authorized which have not caused an irreversible modification of the state of places”, (5), first, second, third, and fourth sentences, (8), (9), and Article 3(1), (2), (4), and (5) of Regional Law of Sardinia No. 20 of 2024.

As regards Article 1(5), the aforementioned judgment stated that, "in the new context of the fundamental principles of the matter, the power, provided for by Article 20(4) of Legislative Decree No. 199 of 2021, to identify suitable areas by regional law, was granted to the regions also with regard to unsuitable areas, with the clarification, however, that unsuitability can never equate to an absolute and aprioristic prohibition (Judgment No. 134 of 2025)”.

The same judgment also declared the constitutional illegitimacy of Article 3(1), (2), (4), (5), and (6) of Regional Law of Sardinia No. 20 of 2024, clarifying that regional legislation cannot provide for a landscape authorization procedure different from that dictated by state legislation, "because regions are not permitted to introduce derogations from state environmental protection institutions, which dictate a uniform regulation, valid throughout the national territory, within which landscape authorization must be included (ex multis, Judgments No. 22 of 2025 and No. 160 of 2021)”.

Finally, by Judgment No. 144 of 2026, paragraph 7-bis of Article 1 of Regional Law of Sardinia No. 20 of 2024 was declared constitutionally illegitimate, as it had provided for the suspension of authorization applications already submitted and the prohibition on submitting new applications for the installation of RES plants in areas not included among suitable ones, pending the adoption of a regional regulation containing the definition of directives concerning the correct application of the discipline of RES plants falling therein.

16.– The first group of challenges raised by the present referring judge, concerning Articles 1(2), (5), and (8), and Article 3 of Regional Law of Sardinia No. 20 of 2024, therefore has as its object provisions already declared constitutionally illegitimate by this Court.

16.1.– According to the consistent jurisprudence of this Court, questions regarding which a declaration of constitutional illegitimacy has intervened are manifestly inadmissible due to the supervening lack of object, from which follows the lapse of the norm which – according to the referring judge – determined the denounced conflict with the invoked constitutional parameters (ex multis, Orders No. 129 of 2022, No. 47 of 2021, No. 203 of 2020).

In light of what was decided in Judgment No. 184 of 2025, the questions concerning Articles 1(2), (5), first sentence, and (8), and Article 3(1), (2), (4), (5), and (6) of Regional Law of Sardinia No. 20 of 2024, raised by the Regional Administrative Court for Latium with reference to Articles 3, 9, 11, 41, 97, and 117(1), (2)(m) and (s), and (3) of the Constitution, also in relation to the principles expressed by Directive 2018/2001/EU, Regulation (EU) 2021/1119, as well as Article 10 of Constitutional Law No. 3 of 2001 and Articles 3 and 4 of the Special Statute, must therefore be declared manifestly inadmissible.

16.2.– Conversely, the questions raised with regard to Article 1(7) of Regional Law of Sardinia No. 20 of 2024 with reference to Articles 3, 9, 11, 41, 97, and 117(1) and (3) of the Constitution, also in relation to the principles expressed by Directive 2018/2001/EU, Regulation (EU) 2021/1119, as well as Article 10 of Constitutional Law No. 3 of 2001 and Articles 3 and 4 of the Special Statute, must be declared unfounded.

Pursuant to the challenged Article 1(7) of Regional Law of Sardinia No. 20 of 2024, in the event that a project falls partly in suitable areas and partly in unsuitable areas, unsuitability prevails. In particular, the referring judge challenges this provision considering it to be in conflict with the European Union principle of the prevailing public interest in the maximum dissemination of energy from renewable sources.

By the aforementioned Judgment No. 184 of 2025, this Court clarified that Article 1(7) of Regional Law of Sardinia No. 20 of 2024 must be understood in the sense that the circumstance that a plant for producing energy from renewable sources is also located on an area declared unsuitable does not represent so much an absolute impediment to its construction, as rather the impossibility of accessing the simplified authorization procedure. Indeed, the final decision regarding the construction of RES plants must be adopted at the conclusion of the individual authorization procedure concerning the specific plant project, and it is in that setting that due consideration must be given to the needs for maximum landscape protection and protected naturalistic areas that justify the non-simplified authorization procedure. Such a system makes it possible to assess concretely the relationship between the two areas and to properly balance nature protection and environmental protection through the reduction of polluting energy sources.

Thus interpreted, the challenged provision has therefore passed the test of constitutional legitimacy. In light of this interpretation, and no new arguments having been proposed in the present proceedings compared to those already examined, the questions are declared unfounded.

17.– The second group of challenges as well, concerning Article 5(1) and (2) of Decree-Law No. 63 of 2024, as converted, and Article 2(2), first sentence, of Legislative Decree No. 190 of 2024, must be examined in light of subsequent case law.

Indeed, subsequently to the filing of the referral order, this Court, with Judgment No. 127 of 2026, declared unfounded questions of constitutional legitimacy concerning the exact same provisions and entirely analogous to the present ones, raised by the same Regional Administrative Court for Latium.

By the aforesaid pronouncement, it was affirmed that Article 5(1) of Decree-Law No. 63 of 2024, as converted, does not preclude, in zones classified as agricultural by current urban planning schemes, the installation of all solar energy production plants, but only that of photovoltaic plants with ground-mounted modules. It follows that the construction of agrivoltaic plants "with modules not mounted on the ground”, i.e., placed in a suitably elevated position so as to preserve the continuity of crop and pastoral activities on the installation site, is permitted.

According to the aforesaid judgment, Article 5 of Decree-Law No. 63 of 2024, as converted, was introduced with the purpose of containing, also for landscape and environmental reasons, the expansion of ground-mounted photovoltaic plants on agricultural soils which could determine significant effects, such as the loss of cultivable soil, the fragmentation of the agrarian landscape, the reduction of biodiversity, and the potential emergence of conflicts with regional and local agricultural and environmental planning instruments.

18.– The arguments put forward in support of the challenges in these proceedings are substantially analogous to those adduced in the order that prompted the aforementioned judgment of unfoundedness, No. 127 of 2026.

The referring judge – as in the cited precedent – omits to consider that the challenged provision does not preclude, in zones classified as agricultural by current urban planning schemes, the installation of all solar energy production plants, but only that of photovoltaic plants with ground-mounted modules.

This Court has repeatedly recognized the overriding relevance of environmental protection under the amended Article 9 of the Constitution (ex multis, Judgments No. 134 and No. 125 of 2025 and No. 105 of 2024), charging public administrations with the task of acting for its effective defense.

It is necessary to reaffirm in these proceedings, furthermore, that Article 9 of the Constitution, even in its current formulation, grants protection not only to the "environment, biodiversity, and ecosystems”, but also to the landscape, of which the agricultural landscape is a fundamental component.

The interest in constructing RES plants cannot therefore be considered as always automatically prevailing over that of landscape protection. And the agricultural landscape is, typically, also "landscape”. As stated in Judgment No. 127 of 2026, the solution provided by the national legislator represents the outcome of a non-unreasonable balancing between different interests, aimed at reconciling agricultural activity with solar energy production.

The challenged provisions are aimed at achieving a non-manifestly unreasonable balancing between interests of equal constitutional significance, all of which are moreover attributable, albeit through different profiles, also to the asset of the environment (the protection of the agricultural landscape, crops, soil, biodiversity, and ecological transition).

Since the referring judge has not put forward new arguments compared to those already examined in Judgment No. 127 of 2026, the questions of constitutional legitimacy concerning Article 5(1) and (2) of Decree-Law No. 63 of 2024, as converted, and Article 2(2), first sentence, of Legislative Decree No. 190 of 2024, raised with reference to Articles 3, 9, 11, and 117(1) of the Constitution, also in relation to the principles expressed by Directive 2018/2001/EU and Regulation (EU) 2018/1999, as amended by Directive 2023/2413/EU and Regulation (EU) 2021/1119, must be declared unfounded.

on those grounds

THE CONSTITUTIONAL COURT

1) declares manifestly inadmissible the questions concerning the constitutional legitimacy of Articles 1(2), (5), first sentence, and (8), and Article 3(1), (2), (4), (5), and (6) of Regional Law of Sardinia No. 20 of December 5, 2024, entitled "Urgent measures for the identification of suitable and unsuitable areas and surfaces for the installation and promotion of renewable energy source (RES) plants and for the simplification of authorization procedures”, raised, with reference to Articles 3, 9, 11, 41, 97, and 117(1), (2)(m) and (s), and (3) of the Constitution, also in relation to the principles expressed by Directive (EU) 2018/2001 of the European Parliament and of the Council of December 11, 2018, on the promotion of the use of energy from renewable sources, by Regulation (EU) 2021/1119 of the European Parliament and of the Council of June 30, 2021, establishing the framework for achieving climate neutrality and amending Regulations (EC) No. 401/2009 and (EU) 2018/1999 ("European Climate Law”), as well as with reference to Article 10 of Constitutional Law No. 3 of October 18, 2001 (Amendments to Title V of Part Two of the Constitution) and Articles 3 and 4 of Constitutional Law No. 3 of February 26, 1948 (Special Statute for Sardinia), by the Regional Administrative Court for Latium, Third Section, by the order indicated in the heading;

2) declares inadmissible the questions concerning the constitutional legitimacy of Annexes A, B, C, D, and E to Regional Law of Sardinia No. 20 of 2024, raised, with reference to Articles 3, 9, 11, 41, 97, and 117(1) and (3) of the Constitution, also in relation to the principles expressed by Directive 2018/2001/EU, Regulation (EU) 2021/1119, as well as Article 10 of Constitutional Law No. 3 of 2001 and Articles 3 and 4 of the Special Statute, by the Regional Administrative Court for Latium, Third Section, by the order indicated in the heading;

3) declares unfounded the questions concerning the constitutional legitimacy of Article 1(7) of Regional Law of Sardinia No. 20 of 2024, raised, with reference to Articles 3, 9, 11, 41, 97, and 117(1) and (3) of the Constitution, also in relation to the principles expressed by Directive 2018/2001/EU, Regulation (EU) 2021/1119, as well as Article 10 of Constitutional Law No. 3 of 2001 and Articles 3 and 4 of the Special Statute, by the Regional Administrative Court for Latium, Third Section, by the order indicated in the heading;

4) declares unfounded the questions concerning the constitutional legitimacy of Article 5(1) and (2) of Decree-Law No. 63 of May 15, 2024 (Urgent provisions for agricultural, fishing, and aquaculture enterprises, as well as enterprises of national strategic interest), converted, with amendments, into Law No. 101 of July 12, 2024, and Article 2(2), first sentence, of Legislative Decree No. 190 of November 25, 2024, entitled "Regulation of administrative regimes for the production of energy from renewable sources, in implementation of Article 26(4) and (5), letters b) and d) of Law No. 118 of August 5, 2022”, raised, with reference to Articles 3, 9, 11, and 117(1) of the Constitution, also in relation to the principles expressed by Directive 2018/2001/EU and Regulation (EU) 2018/1999 of the European Parliament and of the Council of December 11, 2018, on the governance of the Energy Union and Climate Action, amending Directives 94/22/EC, 98/70/EC, 2009/31/EC, 2009/73/EC, 2010/31/EU, 2012/27/EU, and 2013/30/EU of the European Parliament and of the Council, Council Directives 2009/119/EC and (EU) 2015/652, and repealing Regulation (EU) No. 525/2013 of the European Parliament and of the Council, as amended by Directive (EU) 2023/2413 of the European Parliament and of the Council of October 18, 2023, amending Directive (EU) 2018/2001, Regulation (EU) 2018/1999, and Directive 98/70/EC as regards the promotion of energy from renewable sources and repealing Council Directive (EU) 2015/652, and by Regulation (EU) 2021/1119, by the Regional Administrative Court for Latium, Third Section, by the order indicated in the heading.

Decided in Rome, at the seat of the Constitutional Court, Palazzo della Consulta, on July 7, 2026.

Signed:

Giovanni AMOROSO, President

Angelo BUSCEMA, Rapporteur

Roberto MILANA, Director of the Chancery

Filed in the Chancery on October 1, 2026