–

Solvay Chimica Italia SpA, Solvay Specialty Polymers Italy SpA, Solvay Chimica Bussi SpA, Whirlpool Europe Srl, Fenice — Qualità Per L’ambiente SpA, FCA Italy SpA, FCA Group Purchasing Srl, FCA Melfi SpA, Sol Gas Primari Srl, Nuova Solmine SpA, American Husky III, Inovyn Produzione Italia SpA, Sasol Italy SpA, Zignago Power Srl, Radici Chimica SpA, La Vecchia Soc. cons. arl, Santa Margherita e Kettmeir e Cantine Torresella SpA, Zignago Vetro SpA, Chemisol Italia Srl, Vinavil SpA, Italgen SpA, Arkema Srl, Yara Italia SpA and Ineos Manufacturing Italia SpA, by F. Angelini, L. Parola, G. La Rosa, M. Monaco, A. Salzano, G. Berruti and T. Arnoni, avvocati,

–

Erg Power Srl and Erg Power Generation SpA, by L. Acquarone, A. Ricci, M. Saladino and G. Acquarone, avvocati,

–

Eni SpA, Enipower SpA and Versalis SpA, by O. Torrani and P.G. Torrani, avvocati,

–

the Italian Government, by G. Palmieri, acting as Agent, and by F. Sclafani, avvocato dello Stato,

–

the Greek Government, by M. Tassopoulou and D. Tsagkaraki, acting as Agents,

–

the Netherlands Government, by M.K. Bulterman and C.S. Schillemans, acting as Agents,

–

the European Commission, by O. Beynet and G. Gattinara, acting as Agents,

1

These requests for a preliminary ruling concern the interpretation of Article 2(5) and (6), Article 15(7), Article 26(4), Article 28 and Article 37(6)(b) of Directive 2009/72/EC of the European Parliament and of the Council of 13 July 2009 concerning common rules for the internal market in electricity and repealing Directive 2003/54/EC (OJ 2009 L 211, p. 55).

2

The requests have been made in proceedings between Solvay Chimica Italia SpA and a number of other undertakings which own or operate private networks for the distribution of electricity and the Autorità per l’energia elettrica, il gas e il sistema idrico (Authority for Electricity, Gas and Water, Italy) (‘the AEEGSI’), concerning the decision taken by that authority to impose various obligations on those undertakings in respect of, inter alia, third-party access and dispatching.

3

Recitals 3, 29, 30 and 35 of Directive 2009/72 are worded as follows:

…

…

4

Article 1 of Directive 2009/72, entitled ‘Subject matter and scope’, provides:

‘This Directive establishes common rules for the generation, transmission, distribution and supply of electricity, together with consumer protection provisions, with a view to improving and integrating competitive electricity markets in the [European Union]. It lays down the rules relating to the organisation and functioning of the electricity sector, open access to the market, the criteria and procedures applicable to calls for tenders and the granting of authorisations and the operation of systems. It also lays down universal service obligations and the rights of electricity consumers and clarifies competition requirements.’

5

According to Article 2 of that directive, entitled ‘Definitions’:

‘For the purposes of this Directive, the following definitions apply:

…

5.   “distribution” means the transport of electricity on high-voltage, medium-voltage and low-voltage distribution systems with a view to its delivery to customers, but does not include supply;

…

19.   “supply” means the sale, including resale, of electricity to customers;

…

26.   “small isolated system” means any system with consumption of less than 3000 GWh in the year 1996, where less than 5% of annual consumption is obtained through interconnection with other systems;

27.   “micro isolated system” means any system with consumption less than 500 GWh in the year 1996, where there is no connection with other systems;

…’

6

Article 3 of the directive, entitled ‘Public service obligations and customer protection’, states, in paragraph 14 thereof:

‘Member States may decide not to apply the provisions of Articles 7, 8, 32 and/or 34 insofar as their application would obstruct the performance, in law or in fact, of the obligations imposed on electricity undertakings in the general economic interest and insofar as the development of trade would not be affected to such an extent as would be contrary to the interests of the [European Union]. The interests of the [European Union] include, inter alia, competition with regard to eligible customers in accordance with this Directive and Article [106 TFEU].’

7

Article 15 of Directive 2009/72, entitled ‘Dispatching and balancing’, is worded as follows:

‘1.   Without prejudice to the supply of electricity on the basis of contractual obligations, including those which derive from the tendering specifications, the transmission system operator shall, where it has such a function, be responsible for dispatching the generating installations in its area and for determining the use of interconnectors with other systems.

2.   The dispatching of generating installations and the use of interconnectors shall be determined on the basis of criteria which shall be approved by national regulatory authorities where competent and which must be objective, published and applied in a non-discriminatory manner, ensuring the proper functioning of the internal market in electricity. The criteria shall take into account the economic precedence of electricity from available generating installations or interconnector transfers and the technical constraints on the system.

…

7.   Rules adopted by transmission system operators for balancing the electricity system shall be objective, transparent and non-discriminatory, including rules for charging system users of their networks for energy imbalance. The terms and conditions, including the rules and tariffs, for the provision of such services by transmission system operators shall be established pursuant to a methodology compatible with Article 37(6) in a non-discriminatory and cost-reflective way and shall be published.’

8

Article 25 of Directive 2009/72, ‘Tasks of distribution system operators’, provides:

‘1.   The distribution system operator shall be responsible for ensuring the long-term ability of the system to meet reasonable demands for the distribution of electricity, for operating, maintaining and developing under economic conditions a secure, reliable and efficient electricity distribution system in its area with due regard for the environment and energy efficiency.

…

5.   Each distribution system operator shall procure the energy it uses to cover energy losses and reserve capacity in its system according to transparent, non-discriminatory and market based procedures, whenever it has such a function. …

6.   Where a distribution system operator is responsible for balancing the distribution system, rules adopted by it for that purpose shall be objective, transparent and non-discriminatory, including rules for the charging of system users for energy imbalance. Terms and conditions, including rules and tariffs, for the provision of such services by distribution system operators shall be established in accordance with Article 37(6) in a non-discriminatory and cost-reflective way and shall be published.

7.   When planning the development of the distribution network, energy efficiency/demand-side management measures or distributed generation that might supplant the need to upgrade or replace electricity capacity shall be considered by the distribution system operator.’

9

Article 26 of that directive, entitled ‘Unbundling of distribution system operators’ provides:

‘1.   Where the distribution system operator is part of a vertically integrated undertaking, it shall be independent at least in terms of its legal form, organisation and decision-making from other activities not relating to distribution. Those rules shall not create an obligation to separate the ownership of assets of the distribution system operator from the vertically integrated undertaking.

2.   In addition to the requirements under paragraph 1, where the distribution system operator is part of a vertically integrated undertaking, it shall be independent in terms of its organisation and decision-making from the other activities not related to distribution. In order to achieve this, the following minimum criteria shall apply:

…

3.   Where the distribution system operator is part of a vertically integrated undertaking, the Member States shall ensure that the activities of the distribution system operator are monitored by regulatory authorities or other competent bodies so that it cannot take advantage of its vertical integration to distort competition. …

4.   Member States may decide not to apply paragraphs 1, 2 and 3 to integrated electricity undertakings serving less than 100000 connected customers, or serving small isolated systems.’

10

Article 28 of Directive 2009/72, entitled ‘Closed distribution systems’, provides:

‘1.   Member States may provide for national regulatory authorities or other competent authorities to classify a system which distributes electricity within a geographically confined industrial, commercial or shared services site and does not, without prejudice to paragraph 4, supply household customers, as a closed distribution system if:

2.   Member States may provide for national regulatory authorities to exempt the operator of a closed distribution system from:

3.   Where an exemption is granted under paragraph 2, the applicable tariffs, or the methodologies underlying their calculation, shall be reviewed and approved in accordance with Article 37 upon request by a user of the closed distribution system.

4.   Incidental use by a small number of households with employment or similar associations with the owner of the distribution system and located within the area served by a closed distribution system shall not preclude an exemption under paragraph 2 being granted.’

11

Article 32 of Directive 2009/72, entitled ‘Third party access’, states:

‘1.   Member States shall ensure the implementation of a system of third party access to the transmission and distribution systems based on published tariffs, applicable to all eligible customers and applied objectively and without discrimination between system users. Member States shall ensure that those tariffs, or the methodologies underlying their calculation, are approved prior to their entry into force in accordance with Article 37 and that those tariffs, and the methodologies — where only methodologies are approved — are published prior to their entry into force.

2.   The transmission or distribution system operator may refuse access where it lacks the necessary capacity. Duly substantiated reasons must be given for such refusal, in particular having regard to Article 3, and based on objective and technically and economically justified criteria. The regulatory authorities where Member States have so provided or Member States shall ensure that those criteria are consistently applied and that the system user who has been refused access can make use of a dispute settlement procedure. The regulatory authorities shall also ensure, where appropriate and when refusal of access takes place, that the transmission or distribution system operator provides relevant information on measures that would be necessary to reinforce the network. The party requesting such information may be charged a reasonable fee reflecting the cost of providing such information.’

12

Article 37 of that directive, entitled ‘Duties and powers of the regulatory authority’, provides, in paragraph 6 thereof:

‘The regulatory authorities shall be responsible for fixing or approving sufficiently in advance of their entry into force at least the methodologies used to calculate or establish the terms and conditions for:

…

…’

13

Article 30(27) of legge n. 99 — Disposizioni per lo sviluppo e l’internazionalizzazione delle imprese, nonché in materia di energie (Law No 99 concerning measures for the development and internationalisation of undertakings, also as regards energy) of 23 July 2009 (GURI No 176 of 31 July 2009, ‘Law No 99/2009’), provides:

‘In order to guarantee and improve the quality of electricity supply to final consumers connected to the national electricity system through private networks which may have generation capacity …, the Ministero dello sviluppo economico [Ministry for Economic Development] shall lay down, within 120 days of this Law entering into force, new criteria for defining the relations between the network operator, the concessionaire distribution companies, the owner of the private networks and the final consumer connected to those networks. The [AEEGSI] shall implement those criteria for the purpose of balancing and safeguarding acquired rights and shall, in that regard, take account also of the need for rational use of existing resources.’

14

Article 33 of Law No 99/2009 states as follows:

‘… an internal user network … is defined as an electricity network which satisfies all the following conditions:

15

Decreto ministeriale — Attuazione dell’articolo 30, comma 27, della legge 23 luglio 2009, n. 99, in materia di rapporti intercorrenti fra i gestori delle reti elettriche, le società di distribuzione in concessione, i proprietari di reti private ed i clienti finali collegati a tali reti (Ministerial Decree implementing Article 30(27) of Law No 99 of 23 July 2009 on relations between the network operator, the concessionaire distribution companies, the owner of private networks and the final consumer connected to those networks) of 10 December 2010 (GURI No 305 of 31 December 2010) imposes on the operators of private networks, inter alia, the obligation to allow final consumers who are connected thereto to request and obtain physical or virtual connection to the public network and to allow use thereof by the operators of the public network to ensure the right of end-users to obtain connection to the public network.

16

Article 38(5) of decreto legislativo n. 93 — Attuazione delle direttive 2009/72/CE, 2009/73/CE e 2008/92/CE relative a norme comuni per il mercato interno dell’energia elettrica, del gas naturale e ad una procedura comunitaria sulla trasparenza dei prezzi al consumatore finale industriale di gas e di energia elettrica, nonché abrogazione delle directive 2003/54CE e 2003/55/CE (Legislative Decree No 93 implementing Directives 2009/72/EC, 2009/73/EC and 2008/92/EC concerning common rules for the internal market in electricity and natural gas, a Community procedure to improve the transparency of prices charged to industrial end‑users of gas and electricity, and repealing Directives 2003/54/EC and 2003/55/EC) of 1 June 2011 (GURI No 148 of 28 June 2011, ‘Legislative Decree No 93/2011’), provides, inter alia, as follows:

‘Without prejudice to the provisions concerning efficient user systems within the meaning of Article 2(1)(t) of Legislative Decree No 115 of 2008, the internal user networks, as referred to in Article 33 of Law No [99/2009] and the other private networks, as referred to in Article 30(27) of Law No [99/2009], are closed distribution systems …’

17

By deliberazione n. 539/2015/R/eel — Regolazione dei servizi di connessione, misura, trasmissione, distribuzione, dispacciamento e vendita nel caso di sistemi di distribuzione chiusi (Decision No 539/2015/R/eel on the regulation of services for connecting, metering, transmitting, distributing, dispatching and selling in relation to closed distribution systems) of 12 November 2015 (‘Decision No 539/2015’), the AEEGSI, in accordance with Article 38(5) of Legislative Decree No 93/2011, classified internal user networks and the other private networks as ‘closed distribution systems’ referred to in Article 28(1) of Directive 2009/72.

18

Article 8 of Annex A to that decision states that ‘a closed distribution system is a network with an obligation to connect only users which, for the purposes of Article 6 of this Decision, form part of the category of users that may be connected to that closed distribution system’.

19

According to Article 22(1) of that annex, ‘dispatching rules apply in relation to electricity fed into, and taken from the closed distribution system by each user through his connection point to that system’.

20

The applicants in the main proceedings are, in each case, owners or operators of private networks for the distribution of electricity which have been classified, under Article 38(5) of Legislative Decree No 93/2011, in the category of ‘closed distribution systems’ and which, in that capacity, are subject, pursuant to Decision No 539/2015, to various obligations laid down by the AEEGSI.

21

The applicants brought an action before the Tribunale amministrativo regionale per la Lombardia (Regional Administrative Court, Lombardy, Italy) seeking annulment of Decision No 539/2015 on the ground that it is contrary to the provisions of Directive 2009/72, in so far as that decision applies to closed distribution systems the same rules as those applicable to public distribution systems, without laying down rules which take account of the specific nature of closed distribution systems.

22

The pleas in law raised by the applicants in support of that action concern, respectively, the following matters: the obligations to connect third parties and to unbundle accounts and functions, imposed on the operators of closed distribution systems; the application of dispatching charges to every user connected to a closed distribution system without treating that entire system as the sole user of the dispatching service, which was previously the case; and the application of general electricity charges to the consumption of electricity by each user connected to a closed distribution system, even where the electricity is generated within that system.

23

In those circumstances, the Tribunale amministrativo regionale per la Lombardia (Regional Administrative Court, Lombardy) decided to stay the proceedings and to refer to the Court the following questions for a preliminary ruling, which are worded identically in Cases C‑262/17, C‑263/17 and C‑273/17:

24

By order of the President of the Court of 12 June 2017, Cases C‑262/17, C‑263/17 and C‑273/17 were joined for the purposes of the written and oral procedure and the judgment.

25

In response to a request for clarification from the Court of Justice, the referring court informed the Court, on 12 April 2018, that the fifth question referred for a preliminary ruling is no longer relevant, in so far as it concerns rules on unbundling and general electricity charges.

26

By its first question, the referring court asks, in essence, whether Article 2(5) and Article 28(1) of Directive 2009/72 must be interpreted as meaning that systems, such as those at issue in the main proceedings, put in place for the purposes of own consumption before the entry into force of that directive and operated by a private person, to which a limited number of generation and consumption units are connected, and which in turn are connected to the public network, constitute distribution systems falling within the scope of that directive.

27

It should be recalled that the aim of Directive 2009/72, as is apparent from Article 1 thereof, is to establish common rules for, inter alia, the distribution of electricity, with a view to improving and integrating competitive electricity markets in the European Union.

28

Although the concept of ‘distribution system’ is not defined as such by Directive 2009/72, the concept of ‘distribution’ is, however, defined in Article 2(5) thereof as covering the transport of electricity on high‑voltage, medium-voltage and low-voltage distribution systems with a view to its delivery to customers, but excluding ‘supply’, which itself must be understood, in accordance with Article 2(19) of the directive, as referring to the sale of electricity to customers (see, by analogy, judgment of 22 May 2008, citiworks, C‑439/06, EU:C:2008:298, paragraph 45).

29

It follows from those definitions that a distribution system is a system used to transport electricity at high, medium or low voltage (see, by analogy, judgment of 22 May 2008, citiworks, C‑439/06, EU:C:2008:298, paragraph 46).

30

Accordingly, the voltage of the electricity transported is a relevant criterion for determining whether a system constitutes a distribution system within the meaning of Directive 2009/72 (see, to that effect, judgment of 22 May 2008, citiworks, C‑439/06, EU:C:2008:298, paragraph 48).

31

On the other hand, neither the date on which such a system was put into place nor the fact that that system is intended for the purposes of own consumption and operated by a private person — with a limited number of generation and consumption units being connected to that system — constitute relevant criteria in that regard.

32

On the contrary, with regard to the latter circumstance, it must be noted that, according to Article 28(1) of Directive 2009/72, Member States may provide for competent national authorities to classify a system which distributes electricity within a geographically confined industrial, commercial or shared services site and does not, in principle, supply household customers as a closed distribution system if, as the case may be, the operations or the production process of the users of that system are integrated for specific technical or safety reasons, or that system distributes electricity primarily to the owner or operator of the system or their related undertakings.

33

Pursuant to Article 28(2) of Directive 2009/72, Member States may provide for the competent national authorities to exempt the operator of such a closed distribution system, first, from the requirement under Article 25(5) of that directive to procure the energy it uses to cover energy losses and reserve capacity in its system according to transparent, non‑discriminatory and market based procedures and, secondly, from the requirement under Article 32(1) of Directive 2009/72 that tariffs, or the methodologies underlying their calculation, are approved prior to their entry into force in accordance with Article 37 of that directive. In the latter case, system users may, in accordance with Article 28(3) of Directive 2009/72, request the competent national authority to review and approve those tariffs and the methodologies underlying their calculation.

34

It follows from those provisions that systems such as those at issue in the main proceedings, put into place for the purposes of own consumption and operated by a private person, and to which a limited number of generation and consumption units are connected, constitute distribution systems falling within the scope of Directive 2009/72, since the competent national authorities may classify them as a closed distribution system within the meaning of Article 28(1) of that directive, and the Member States have, furthermore, only the option, but not the obligation, to exempt them, in accordance with Article 28(2) of the directive, from the two requirements referred to in that provision.

35

It must also be noted, with regard to the limited size of the system, that Directive 2009/72 refers to such a criterion, in Article 2(26) and (27) only for the purposes of defining the concepts of ‘small isolated system’ or ‘micro isolated system’, the EU legislature having thus not intended to exclude particular distribution systems from the scope of that directive by reason of their size or consumption of electricity (see, by analogy, judgment of 22 May 2008, citiworks, C‑439/06, EU:C:2008:298, paragraph 49).

36

The foregoing considerations are, moreover, supported by the aim of Directive 2009/72, which is to bring about the internal market in electricity (see, to that effect, judgment of 22 May 2008, citiworks, C‑439/06, EU:C:2008:298, paragraph 44).

37

Accordingly, systems such as those at issue in the main proceedings, which are undeniably used to transport electricity at high, medium or low voltage for sale to final customers, constitute distribution systems falling within the scope of Directive 2009/72.

38

Consequently, the answer to the first question is that Article 2(5) and Article 28(1) of Directive 2009/72 must be interpreted as meaning that systems, such as those at issue in the main proceedings, put in place for the purposes of own consumption before the entry into force of that directive and operated by a private person, and to which a limited number of generation and consumption units are connected, and which in turn are connected to the public network, constitute distribution systems falling within the scope of that directive.

39

By its second and fourth questions, the referring court asks, in essence, whether Article 28 of Directive 2009/72 must be interpreted as meaning that the Member States may exempt systems, such as those at issue in the main proceedings, only from the requirements laid down in paragraph 2 of that provision concerning the closed distribution systems to which that provision refers and those laid down in Article 26(4) of that directive, or whether they may also include those systems in a separate category of distribution systems with a view to granting them exemptions not provided for in that directive.

40

As is already apparent from paragraphs 32 to 34 of the present judgment, a Member State which provides for the competent national authorities to classify systems which fulfil the conditions set out in Article 28(1) of Directive 2009/72 as closed distribution systems may also provide, in accordance with Article 28(2) of that directive, for those authorities to exempt the operator of those systems from the requirements referred to in Article 25(5) and Article 32(1) of that directive.

41

It thus follows clearly from the actual wording of Article 28(2) of Directive 2009/72 that the systems classified by the competent national authorities as closed distribution systems may only, on the basis of that provision, be exempted from the requirements to which it refers, in order to avoid, as is apparent from recital 30 of that directive, imposing on the operators of those systems obligations which could constitute an unnecessary administrative burden because of the particular nature of the relationship between those operators and the users of those systems.

42

In the present case, it is apparent from the order for reference, and it is not, moreover, disputed, that the systems at issue in the main proceedings have been classified by the competent national authority as closed distribution systems within the meaning of Article 28(1) of Directive 2009/72.

43

In that capacity, those systems may, therefore, if Italy has exercised the option provided for in Article 28(2) of the directive, benefit only from the exemptions referred to in that provision.

44

Nevertheless, as the Advocate General observed, in essence, in points 52 to 58 of his Opinion, there is nothing to prevent a closed distribution system from also benefiting, in other capacities, from additional exemptions provided for in Directive 2009/72.

45

In particular, in must be noted in that regard that Article 26(4) of Directive 2009/72 allows Member States to exempt integrated electricity undertakings serving less than 100000 connected customers from the unbundling requirements laid down in Article 26(1) to (3) of that directive, in order to avoid imposing, in accordance with recital 29 of the directive, a disproportionate financial and administrative burden on small distribution system operators.

46

It follows from the findings reached by the referring court that the systems at issue in the main proceedings are likely to be eligible for that exemption, since they may not, in principle, supply household customers and they connect a limited number of generation and consumption units within a geographically confined site.

47

Moreover, it is apparent from the response provided by the referring court to the request for clarification sent by the Court of Justice that the national legislation at issue in the main proceedings now exempts those systems, in accordance with Article 26(4) of Directive 2009/72, from the unbundling requirements laid down in Article 26(1) to (3) thereof.

48

In any event, it must be noted that Member States cannot include systems, such as those at issue in the main proceedings, which fall within the scope of Directive 2009/72, in a separate category of distribution systems from the categories expressly established by that directive, with a view to granting them exemptions not provided for in the directive.

49

Admittedly, as is apparent from recitals 29 and 30 of Directive 2009/72, the specialised nature of certain types of distribution system, which include closed distribution systems, may give Member States grounds for deciding to exempt those systems from certain obligations laid down by that directive in order not to impose an unnecessary administrative burden on them.

50

However, it must be noted that those considerations are specifically reflected in Article 26(4) and Article 28(2) of Directive 2009/72, which expressly determine the exemptions for which such distribution systems may be eligible.

51

Consequently, the answer to the second and fourth questions is that Article 28 of Directive 2009/72 must be interpreted as meaning that systems, such as those at issue in the main proceedings, which have been classified by a Member State as closed distribution systems within the meaning of Article 28(1) of that directive, may, in that capacity, only be exempted by that Member State from the requirements laid down in Article 28(2) of the directive, without prejudice to the fact that those systems may otherwise be eligible for other exemptions provided for in that directive, in particular the exemption set out in Article 26(4) thereof, if they meet the conditions laid down therein, which it is for the referring court to ascertain. In any event, that Member State may not include those systems in a separate category of distribution systems with a view to granting them exemptions not provided for in that directive.

52

By its third question, the referring court asks, in essence, whether Article 32(1) of Directive 2009/72 must be interpreted as precluding national legislation, such as that at issue in the main proceedings, which provides that closed distribution systems within the meaning of Article 28(1) of that directive are not subject to the obligation to provide third-party access, but must provide access only to third parties falling within the category of users that may be connected to those systems, those users having a right of access to the public network.

53

It should be borne in mind that, in accordance with the first and second sentences of Article 32(1) of Directive 2009/72, Member States are required to implement, for all eligible customers, a system of third party access to the transmission and distribution systems, which must be based on published tariffs and applied objectively and without discrimination between system users. According to the third sentence of Article 32(1) of that directive, Member States must, moreover, ensure that those tariffs, or the methodologies underlying their calculation, are approved prior to their entry into force, in accordance with Article 37 of the directive, and that those tariffs, and the methodologies — where only methodologies are approved — are published prior to their entry into force.

54

As the Court has repeatedly held, open third-party access to those systems, established in the first and second sentences of Article 32(1) of Directive 2009/72, is one of the essential measures which Member States are required to implement in order to bring about the internal market in electricity (see, by analogy, judgments of 22 May 2008, citiworks, C‑439/06, EU:C:2008:298, paragraph 44; of 9 October 2008, Sabatauskas and Others, C‑239/07, EU:C:2008:551, paragraphs 31, 33 and 46; and of 29 September 2016, Essent Belgium, C‑492/14, EU:C:2016:732, paragraph 76).

55

As is apparent from recital 3 of Directive 2009/72, the directive aims to achieve a fully open market which enables all consumers freely to choose their suppliers and all suppliers freely to deliver to their customers.

56

In that regard, although Article 32(1) of Directive 2009/72 leaves the Member States free to take the measures necessary to establish a system of third-party access to transmission or distribution systems, the Member States therefore having authority, in accordance with Article 288 TFEU, over the form and the methods to be used to implement such a system, the fact remains that, having regard to the importance of the principle of open access to transmission or distribution systems, that margin of discretion does not authorise them to depart from that principle except in those cases where that directive lays down exceptions or derogations (see, by analogy, judgment of 22 May 2008, citiworks, C‑439/06, EU:C:2008:298, paragraph 55).

57

Thus, it is apparent from Article 3(14) of Directive 2009/72 that Member States are permitted not to apply the provisions of Article 32(1) of that directive providing for non-discriminatory third party access to the transmission and distribution systems in so far as the application of those provisions would obstruct the performance, in law or in fact, of the public service obligations thus imposed on electricity undertakings, provided that Member States ascertain that the performance of those obligations cannot be achieved by other means which do not impact adversely on the right of access to the systems, which is one of the rights enshrined in Directive 2009/72 (see, by analogy, judgments of 22 May 2008, citiworks, C‑439/06, EU:C:2008:298, paragraph 60, and of 29 September 2016, Essent Belgium, C‑492/14, EU:C:2016:732, paragraph 91).

58

On the other hand, as is apparent from the answers to the first question and the second and fourth questions, in particular from paragraphs 33, 34, 40 and 41 of the present judgment, it follows from the very wording of Article 28(2) of Directive 2009/72 that, on the basis of that provision, the closed distribution systems referred to in Article 28(1) of that directive may only be exempted from two specific requirements, namely, first, that of procuring the energy they use to cover energy losses and reserve capacity in the system according to transparent, non‑discriminatory and market based procedures and, secondly, that of ensuring that tariffs, or the methodologies underlying their calculation, are approved prior to their entry into force, in which case, in accordance with Article 28(3) of the directive, system users may request the competent national authority to review and approve those tariffs and the methodologies underlying their calculation.

59

It follows that, although a closed distribution system may be exempted from the requirement, laid down in the third sentence of Article 32(1) of Directive 2009/72, to have its tariffs or methodologies approved in advance, it may not, however, be exempted from the requirement of open third-party access laid down in the first and second sentences of Article 32(1) of that directive.

60

In that regard, it must also be pointed out that, although Article 32(2) of Directive 2009/72 provides that the operator of a distribution system may refuse access where it lacks the necessary capacity, on condition that duly substantiated reasons are given for such refusal, that possibility of refusing access to the system is to be assessed on a case-by-case basis and does not authorise the Member States to lay down those derogations in a general manner without, in respect of each operator, a concrete assessment of the technical incapacity of the system to meet the demand for access from third parties (see, by analogy, judgment of 22 May 2008, citiworks, C‑439/06, EU:C:2008:298, paragraph 57).

61

Consequently, the answer to the third question is that Article 32(1) of Directive 2009/72 must be interpreted as precluding national legislation, such as that at issue in the main proceedings, which provides that closed distribution systems within the meaning of Article 28(1) of that directive are not subject to the obligation to provide third-party access, but that they must provide access only to third parties falling within the category of users that may be connected to those systems, those users having a right of access to the public network.

62

By its fifth question, the referring court asks, in essence, whether Article 15(7) and Article 37(6)(b) of Directive 2009/72 must be interpreted as precluding national legislation, such as that at issue in the main proceedings, which provides that dispatching charges for the users of closed distribution systems are calculated on the basis of the electricity exchanged with that system by each of its users through their connection point to that system.

63

As is apparent from the provisions of Articles 15 and 25 of Directive 2009/72, dispatching enables the electricity system operator to dispatch the generating installations in a specific area in order to, inter alia, procure the energy it uses to cover energy losses and reserve capacity in its system, balance the distribution system and ensure the proper functioning of the internal market in electricity.

64

Under Article 15(7) and Article 37(6)(b) of Directive 2009/72, rules adopted by a transmission system operator for balancing the electricity system, including rules for the charging of system users, must be established in an objective, transparent and non-discriminatory way and must reflect, as is also apparent from recital 35 of that directive, the costs, according to a methodology which ensures that balancing services are provided in the most economic manner possible and provide appropriate incentives for users to balance their input and off-takes. Article 25(6) of the directive imposes, in essence, a similar requirement on the operator of a distribution system.

65

In the present case, it is apparent from the information before the Court that the national legislation at issue in the main proceedings has been amended to the effect that dispatching charges owed to the operator of the public network, namely Terna SpA, by the users of a closed distribution system are now no longer calculated on the basis only of the electricity exchanged with the public network by the closed distribution system as a whole through the connection point of that closed system to the public network, but on the basis of the electricity exchanged with the closed distribution system by each of its users through their connection point to that system, thus aligning the rules applicable to those users with the rules applicable to users of the public network. It follows that dispatching charges are also applicable to the electricity generated within the closed distribution system.

66

According to settled case-law, the general principle of equal treatment, as a general principle of EU law, requires that comparable situations must not to be treated differently and different situations must not to be treated in the same way unless such treatment is objectively justified (judgment of 16 December 2008, Arcelor Atlantique et Lorraine and Others, C‑127/07, EU:C:2008:728, paragraph 23).

67

In that regard, it must first of all be noted that the users of systems, such as those at issue in the main proceedings, which fall, under national law, within the category of ‘closed distribution systems’, are connected to the public network and that, to that extent, they are likely to make use, like any other user of such a network, of dispatching. The applicants in the main proceedings cannot, therefore, validly maintain either that the users of those closed distribution systems do not generate any costs for the provider of the dispatching service or, accordingly, that the national legislation at issue in the main proceedings makes them bear the costs of a service from which they do not benefit.

68

However, it is not in dispute that since the users of a closed distribution system, unlike those other users of the public network, essentially consume, in accordance with Article 28(1)(b) of Directive 2009/72, the electricity generated internally by that closed distribution system, they make only residual use of the public network, when what is generated by the closed distribution system is insufficient to meet the needs of its users, in particular, in the event of a sudden and unexpected increase in the system’s internal demand or an interruption of the generation units connected to that system on account of intervention or malfunction. Apart from such exceptional situations, it is, therefore, essentially for the operator of the closed distribution system itself to ensure the balancing of generation and consumption within that system, like the task assumed by Terna in respect of the public network.

69

In those circumstances, first, the users of a closed distribution system do not seem to be in the same situation as the other users of the public network. Secondly, it appears that the provider of the dispatching service for the public network has to bear the limited costs in respect of the users of a closed distribution system, since those users make only residual use of that service. It is, however, for the referring court to ascertain whether those circumstances exist.

70

Should those circumstances exist, as the Advocate General observed in point 105 of his Opinion, national legislation, such as that at issue in the main proceedings, which provides that dispatching charges for the users of closed distribution systems are to be calculated according to the same methodology as that used to calculate the charges owed by the other users of the public network would be liable to be considered discriminatory, in the absence of any objective justification.

71

In particular, it does not appear to be excluded that such a methodology may not be sufficiently linked to the costs of dispatching, in accordance with the requirements stemming from Article 15(7) and Article 25(6) of Directive 2009/72.

72

Furthermore, since the amount of the dispatching charges owed by the users of closed distribution systems is not linked to the volume of electricity exchanged with the public network, that methodology also seems incapable of incentivising those users, as provided for in Article 37(6)(b) of the directive, to balance their generation and consumption of electricity in order to limit as far as possible the use of dispatching.

73

Admittedly, it could be legitimate for a Member State to impose on the users of a closed distribution system having access to the public network dispatching charges the amount of which is not calculated only on the basis of the electricity actually exchanged with the public network, if it could be shown, for example, that such an amount corresponds to a specific cost for the provider of the dispatching service linked to the very possibility for the users of a closed distribution system of exchanging electricity with the public network by having recourse to dispatching. However, none of the interested parties that have participated in the present proceedings has referred to the existence of such a specific cost.

74

In its written observations and at the hearing, the Italian Government also argued that the users of a closed distribution system can decide to regroup in order to constitute a single dispatching point, in which case dispatching charges would be calculated only on the basis of the electricity exchanged with the public network.

75

However, it must be pointed out that the applicants in the main proceedings argued that such regrouping had no impact on the calculation of those charges. Moreover, there is nothing in the documents before the Court to substantiate the Italian Government’s claims.

76

In those circumstances, it is for the referring court alone to ascertain the truth of those claims, which concern the interpretation of national law alone.

77

Consequently, the answer to the fifth question is that Article 15(7) and Article 37(6)(b) of Directive 2009/72 must be interpreted as precluding, in the absence of an objective justification, national legislation such as that at issue in the main proceedings which provides that dispatching charges for the users of a closed distribution system are calculated on the basis of the electricity exchanged with that system by each of its users through their connection point to that system, should the users of a closed distribution system prove not to be in the same situation as the other users of the public network and should the provider of the dispatching service for the public network bear the limited costs with regard to those users of a closed distribution system, which it is for the referring court to ascertain.

78

Since these proceedings are, for the parties to the main proceedings, a step in the action pending before the national court, the decision on costs is a matter for that court. Costs incurred in submitting observations to the Court, other than the costs of those parties, are not recoverable.

On those grounds, the Court (First Chamber) hereby rules: