Rete Gas

PLAN FOR THE IMPLEMENTATION OF NEW CAPACITY AND FOR DEVELOPMENT

Document prepared by Snam Rete Gas S.p.A. for compliance with the Delibera 137/02 of the Autorità per l’energia elettrica e il gas.

September 1st, 2003

1 Foreword

Snam Rete Gas S.p.A. publishes the plan for the implementation of new capacity and the development of its transportation network prepared on the basis of currently available information and on the basis of relationships with its own clients, securing transparency and impartiality among users in conformity with provisions of Directive no. 98/30/EC of the European Parliament and of Law Decree no. 164/2000.

The present document has been prepared in compliance with the article 4 subsection 1 letter b, of Delibera no. 137/02 of the Autorità per l’energia elettrica e il gas.

The projects that figure in the programme result from studies carried out by Snam Rete Gas on the basis of its own forecasts of capacity requirements.

The infrastructure development plans included in this document are not binding for Snam Rete Gas that, therefore, reserves the right to modify them every time that new elements, such as for example evolutions of market requisites different from the current hypotheses, require it, as provided for in article 4 subsection 2 of Delibera no. 120/01 of the Autorità per l’energia elettrica e il gas.

2 Index

1 PLANNED INFRASTRUCTURES 1.1 Complete Programme 1.2 Transportation on the National Network 1.3 Transportation on the Regional Network 1.4 Main projects

2 PLAN OF CAPACITIES 2.1 Entry Points interconnected with foreign pipelines 2.2 Exit Points interconnected with foreign pipelines 2.3 Methodology for calculating capacities 2.4 Operational constraints and boundary conditions used for simulations 2.5 Interruptible capacities 2.6 Simulation Programs

3 ATTACHMENTS

3 1 PLANNED INFRASTRUCTURES

4 1 PLANNED INFRASTRUCTURES

1.1 Complete programme

The plan for implementation of new capacity and for development includes projects whose construction is under way and those whose start is scheduled in future years, within the next four-year term. The level of project definition included in the plan changes, downwards, depending on their time collocation.

Furthermore Snam Rete Gas has planned to put out some sections of natural gas pipelines and some plants, which, in total, have no impact on the reliability of the network of natural gas pipelines, or on the availability of transportation capacity.

The development projects have been evaluated on the basis of transportation scenarios that reflect forecasts of consumptions of natural gas in , relationships with subjects interested in starting-up new off-take points and those with users who use capacity in the inlet and outlet points. These projects represent approximately 80% of the plan and are characterised by the presence of significant works that will make it possible in the near future to inject quantities of gas onto the Italian network from the main pipelines supplying the Country. The remaining 20% of the plan includes different types of interventions including those aimed preserving existing infrastructures. Preservation projects have been identified on the basis of information available on the status of existing pipelines.

Works relating to Transportation on the National Network represent approximately 60% of the plan, while those relating to Transportation on the Regional Network represent approximately 40% of the plan.

In total the Snam Rete Gas Group plan provides for development of the network of gas pipelines from the 30,160 km forecast for the end of 2003, to the 31,700 km planned for the end of the 2003-2006 four-year term, with a further increase of up to approximately 31,900 km in the following years.

5 Similarly, the increase of installed capacity in the Compressor stations is forecast in the plan from the current 625 MW (37 compressor units in 11 stations), up to approximately 800 MW in the four-year term (seven new units to be installed in existing stations). A further increase of approximately 50 MW (one new station with three units) is planned in the following years.

6 1.2 Transportation on the National Network

86% of the National Network Development Plan is composed of projects already being implemented or that will be started during 2003, while the remaining 14% are planned to start in the following years.

These infrastructures are destined mainly to reinforce the importation system, and will include the completion of works dedicated to importation from Russia and those for connection from the LNG terminal of Panigaglia, carrying on with activities related to the new Gela – Enna gas pipeline and works for development of the pipelines system from the South. These works will be presented in detail in paragraph 1.4. Furthermore, phases of design and permits related to possible further developments of the Transmed backbone have started.

The remaining development projects are aimed at reinforcing other main national transportation pipelines, mainly located in the areas of Apulia, Southern Piedmont and the North-East. These include works related to the Bernalda – Palagiano natural gas pipeline which are under completion and the recently started works to develop the connection to the storage of Collato and of the Verona - Trento (section Bosentino-Aldeno) natural gas pipeline. Planned works for reinforcing the Alessandria – Oviglio, and Verona-Trento (section Vigasio-Sona) natural gas pipelines have not yet started.

In total the plan will develop the National Network from approximately 8,000 km, planned for the end of 2003, to approximately 8,600 km, at completion of plan. The compression system will be developed from the current 625 MW, distributed over 37 compressor units, to approximately 850 MW at completion of plan, resulting from the installation of 10 new compressor units, for a total of approximately 220 MW of new compression capacity.

7 1.3 Transportation on the Regional Network

44% of the National Network Development Plan is composed of projects already being implemented or that will be started during the current year, while the remaining 56% are planned to start in the following years.

These infrastructures are aimed at extending and reinforcing of the regional transportation network, for which completion of the following natural gas pipelines is planned: Valtellina, Bolzano – Bressanone – Brunico and Contursi – Battipaglia. Work for the Giarratana – Solarino natural gas pipeline, to develop supply to the industrial centre of Brindisi and to develop the connection to Abbadia Lariana have started. In addition, reinforcements are planned in the area of Southern Piedmont (Oviglio - Ponti and Cherasco – Cuneo gas natural pipelines), in (Casaletto – , Mornico al – Zanica and – Ospitaletto natural gas pipelines), in Apulia (Triggiano – Locorotondo natural gas pipeline), as well as reinforcement of the network of Umbria ( – Perugia natural gas pipeline), the Forlì - Faenza natural gas pipeline loop and the Palaia – Livorno natural gas pipeline.

Furthermore, on the basis of relationships developed with the subjects interested in connecting their own sites to the transportation network and of feasibility studies carried out, many connections of new thermoelectric power plants, of industrial plants and of distribution networks scattered in the eight territorial districts, have been identified. Some of these works have already started. Meanwhile for the remaining ones, for which to date no defined contractual agreements exist, actual planning and implementation is subject to confirmation of interest by the requesting subjects and to the subsequent conclusion of agreements for connection. Started initiatives concern 7 new thermoelectric plants with capacity of approximately 4,000 MW; meanwhile implementation of approximately 100 connections in total per year is planned for the remaining types. At the same time, implementation of connections included in the plan of Methanization of the South goes ahead.

In total the plan will develop the Regional Network of Snam Rete Gas from 22,160 Km, in the year 2003 to approximately 23,100 km, at the end of 2006, and an increase of approximately 200 km in the following years, with a total increase of approximately 1,200 Km.

8 1.4 Main projects

To complete the description of the plan, hereinafter the most significant infrastructures are indicated in terms of their impact on effectiveness of the transportation system. These projects represent approximately 50% of the total and they are related to the implementation of works substantially distributed all along the Snam Rete Gas transportation network.

9 1.4.1 Additional Importation from Russia The project consists in laying approximately 190 Km of 48” pipeline and 43 km of 56" pipeline (section Camisano-Zimella), parallel to existing 36” and 42” lines between Tarvisio (province of Udine) and Zimella (province of Verona).

The above-mentioned works, 97 km of which are operating (sections Flaibano-Oderzo and Malborghetto-Bordano), will be completed within the year 2006, thus allowing for an increase in importation capacity from Russia, at the entry point of Tarvisio, up to 103 Mm3/day.

1.4.2 Importation from Northern Europe The project consists in replacing 42 Km of 34” pipeline with a new 48” pipeline (section Gries Pass-Masera), laying 134 Km of 48” pipeline alongside the existing 34” one in the Masera-Mortara section (sections already completed) and in implementing a new compressor station provided with three units of approximately 12 MW each one.

The above-mentioned works, completed in the year 2002, have increased imported volumes at the entry point of Masera to approximately 60 Mm3/day. Additional works and restorations are under way.

10 1.4.3 Gela – Enna natural gas pipeline This project meets the requirement to enable connection of the importation line coming from Libya. Furthermore, connected to implementation of the Giarratana-Solarino natural gas pipeline, it allows for closure of network ring operating for supply of the area of South-Eastern Sicily.

The project consists in implementing a natural gas pipeline 66.5 km long and 36” in diameter, which connects the landing point of the sealine, located in Sicily in the vicinity of Gela, to the national gas pipeline network. Interconnection is planned on the Transmed natural gas pipeline at the level of the compressor station of Enna.

Construction of the natural gas pipeline has started and its commissioning is planned in the year 2004. Its implementation, together with the “Transmed Reinforcement” initiative, will provide capacity of approximately 25 Mm3/day at the Gela entry point, providing, furthermore the above-mentioned advantages for the South-Eastern Sicily.

11 1.4.4 Reinforcement of Transmed During the year 2002, SNAM Rete Gas launched investments necessary for implementing works to reinforce the backbone importation network consisting of:  Implementation of a 3rd line (DN1200) with a total of approximately 290 km in the Enna-Montalbano, Palmi-Martirano, Campochiaro-Sulmona sections;  Reinforcement of the existing stations of , Montesano, Melizzano, Gallese, Terranuova by means of the addition of one extra compressor unit;  Reinforcement of the station of Messina by means of the addition of two new compressor units;  Adjustment of piping and auxiliary plants in the existing stations.

Commissioning of these works is planned within the year 2006; they will provide approximately 86 MSm3/day at the entry point of Mazara del Vallo and the already mentioned 25 MSm3/day at the entry point of Gela.

1.4.5 Pontremoli – Parma natural gas pipeline The project involves the laying of approximately 70 Km of pipeline DN750 between the site of Pontremoli and Parma, 39 km of which have already been

12 implemented. The above-mentioned work will be completed within the year 2004 and will form a new connection of the LNG terminal at Panigaglia to the National Network. The natural gas pipeline will be laid alongside the existing section of Cortemaggiore – La Spezia, which follows a different line, thus increasing total capacity to 13 Mm3/day.

1.4.6 Compressor station of Poggio Renatico The project is at the study stage and involves the implementation of a new compressor station in the vicinity of the distribution node of Poggio Renatico (approximately 20 Km from Minerbio). It will allow for compression of increasing volumes of gas coming from the importation pipelines from Russia and from North Africa that converge in the area of Minerbio and transportation on the National Network of natural gas injected by the planned LNG terminal of Porto Viro (province of Rovigo), which is planned to join in the area of Minerbio by means of an apposite connection. Programming of commissioning of this station will depend on the development of capacity plans of the above-mentioned entry points.

13 1.4.7 Natural gas pipeline for Valtellina This natural gas pipeline will connect Calco to and increase supplies in the already supplied areas of Lecchese, High Lario, Low Valchiavenna and Valtellina, and allow the methanization of Valsassina and of Valtellina. The work is composed of two sections. The first (Calco – Piantedo) with a diameter of 30” and length of 64 km, was commissioned in the year 2001; additional works and restorations are under way.

The second section (Piantedo – Berbenno) with a diameter of 20” and length of 25.2 km, will be completed by the year 2003.

1.4.8 Alessandria – Oviglio natural gas pipeline and Oviglio-Ponti natural gas pipeline The projects involve the laying of approximately 12 km of pipeline in the National Network (section Alessandria – Oviglio) and approximately 38 km of pipeline in the Regional Network (section Oviglio-Ponti) both with a diameter of 30”, which will reinforce the existing transportation lines of the South-Western Piedmont and Liguria, avoiding bottle-necks on existing networks, considering also the medium-term development of natural gas consumption in the above- mentioned area.

14 1.4.9 Giarratana- Solarino natural gas pipeline The project consists in laying 38 km of 24”-diameter pipeline and completes the continuity of installations between both the Calderari – Bivio Gigliotto – Gela line to the West, and the Sparacollo – Carcaci – Priolo line to the East, forming a ring structure between terminals of the above-mentioned lines. Commissioning of this work is planned within the year 2004 and will allow for transportation in the consumption areas of Priolo, Augusta and Catania, with an increase of redelivery pressures to users, and with development of consumptions estimated at 3 Mm3/day at least in this area.

The natural gas pipeline will also enable further development of natural gas consumption in the civil sector, allowing for possible connection of interested municipalities along the route.

1.4.10 Reinforcement of connection for the industrial centre of Brindisi The project involves the implementation of a 42”-diameter pipeline of approximately 10 km.

Commissioning of this work is planned for the first months of 2004 and will allow for transportation of quantities of natural gas required for the development of relevant thermoelectric projects in the Brindisi area, with capacities currently estimated at 6 Mm3/day with the possibility of developing a further 6 Mm3/day.

15 Furthermore it will be possible to connect to it the planned LNG terminal, and thus makes it possible for natural gas injected by it to be transported towards the national network.

1.4.11 Initiative for the region Apulia The project involves the implementation of connections and related reinforcement of the natural gas pipeline network in the Apulia region. These works will be implemented in three phases to be completed in the year 2004.

1.4.12 Bolzano – Bressanone – Brunico natural gas pipeline Investment consists in implementation of two pipelines: -the first section, Bolzano – Bressanone natural gas pipeline, involves the laying of 54.8 km of 20”-diameter pipeline 46 Km of which were commissioned in the year 2002; -the second section, Bressanone – Brunico natural gas pipeline, involves the laying of 37.7 km of 12”-diameter pipeline to be commissioned in the year 2004.

Implementation of this natural gas pipeline will allow quantities of gas required to meet the increase in consumption in the already-supplied areas of Bolzano and Merano to be transported, further to the extension of methanization in user basins not yet methanized.

16 2 PLAN OF CAPACITIES

17 18 19 2.3 Methodology for calculating capacity For the purposes of dimensioning and operating the system, marketing transportation services, and fulfilling the requirements of current legislation and the resolutions of the Autorità per l’energia elettrica e il gas, Snam Rete Gas carries out periodic analyses of its transportation system, aimed at establishing capacities at entry points interconnected with external systems.

On the basis of conventions commonly used by European operators, transportation capacity is the highest quantity of gas that may be injected into the system during the Gas-day, at a specific point and transported from there to the consumption centres, in compliance with the technical and operational constraints defined in each section of the pipelines and of the highest performances of plants erected along the same pipelines. These capacities are estimated by means of hydraulic simulations of the network, performed in appropriate transportation scenarios and according to acknowledged technical standards. These simulations are carried out under steady state conditions and represent the average transportation day, with an established modelling of the network, of plants and of boundary conditions. The considered constraints take into account these approximations in the model used and constitute a security margin that guarantees actual availability of calculated transportation capacities, under real operating conditions.

Transportation capacity may be made available to users with transportation services of a firm or interruptible type. Estimation of firm transportation capacities, whose availability must be guaranteed in any situation and at any period of the thermal year, refers to cautious transportation scenarios and constraints. On the contrary, estimation of interruptible capacities uses existing transportation margins under special conditions or with less severe constraints.

The transportation of the firm capacity is guaranteed under every possible operational condition, since it is calculated taking into account the most severe market scenarios; it ensures that for any considered year, it is not possible to foresee a worse transportation situation other than unavailability or failures in the transportation structure, which cannot be foreseen in advance. The scenarios that have just been described may be considered as “special” operating conditions. Under “normal conditions”, which correspond to the usual operating conditions, the transportation capacities are prevalently subject to market fluctuations, in terms of entities and collocation, and to unavailability of plants, for example for ordinary or extraordinary maintenance. Under normal conditions it is possible to use transportation structures more, if less restrictive technical and operational constraints than those used for verifying special conditions, are assumed. With respect to inlet capacity values calculated under special conditions, additional capacity values, published as interruptible capacities, thus subject to reduction or interruption, depending on operating condition requirements, are obtained from the transport simulations of normal conditions.

20 Therefore, it is possible to summarise that performances of the transportation network may fluctuate between two conditions: a “normal” condition that may be encountered during every day operations, but that cannot be guaranteed during the whole year, to which “interruptible” capacity availability corresponds and a “special” condition that may be encountered and guaranteed every day of the year, to which the “firm” capacity corresponds.

In turn, interruptible capacity may be subdivided into two reference groups: annual and seasonal.

Some general information on the entire transportation capacity calculation process, including the technical characteristics of the simulation system are indicated below, to be utilised by all users.

2.4 Operational constraints and boundary conditions used in simulations

2.4.1 Delivery pressures For the purpose of transportation verifications, reference is made to delivery pressures at the entry points, which have been defined, jointly with the foreign companies involved, on the basis of dimensioning calculations carried out in order to define in a complete way the reinforcement required for both systems, with respect to increases in volumes of transiting gas programmed on the basis of market requirements. The assumed pressures constitute a fundamental reference for system dimensioning and operational service, and for this reason, in compliance with the Network Code they are notified to users by publication on the Transporter’s web site.

Currently valid delivery pressures are illustrated below: Entry Point Minimum contractual pressure (barg) Tarvisio 56.5 Gorizia 70 Gries Pass 49 Mazara del Vallo 75

21 2.4.2 Maximum pressures of pipelines The maximum operating pressure of pipelines cannot exceed the maximum project pressure, a value that normally coincides with the pressure value from CPI, i.e. the pressure for which the authorisation is given by the competent authority (VVFF). In order to avoid exceeding the pressure by CPI along the pipelines, which could be caused by changes in elevation or by transitory transportation regimes, control and monitoring pressure systems are used, calibrated on “limit” pressure values of 1T2 bar less than the allowed limit (the value is determined each time taking into account the system control tolerances). In some cases lower maximum operational values than those above are used on a temporary basis. These values are also taken into account when calculating capacity.

Some sections of pipelines relating to importation from Northern Europe and Russia, constructed in the Seventies and almost completely doubled or tripled with new pipelines, are operated at lower pressures down to 55 bar.

2.4.3 Minimum pressure along the pipelines In relation to the forecast configuration, in particular points of the transportation network, the minimum pressures required to guarantee system performances are identified. In particular, the minimum pressure at inlet of the compressor station normally assumes the value of 55 bar for importations from the South, and of 50 bar for those from the North. Similarly, minimum pressures are assumed at particular network points defined depending on the guarantee of minimum contractual pressures at Redelivery Points; the points concerned are the distribution nodes of Mortara and Sergnano, in which the lowest value is 50 bar.

It must be noted that modulation of loads withdrawn by the market during the day generate fluctuation of pressures on the network, reaching lower values than those shown by transportation simulations under steady state conditions. Pressure values assumed as permissible for any point on the network take into account both these daily fluctuations and those attributable to transients due to the most common operational conditions.

2.4.4 Design and operation of compressor stations As regards operating the compressor stations, the transportation conditions that require utilisation of turbo compressors limited to the maximum rated performances, to which an appropriate reduction factor is applied, are considered permissible. These coefficients allow for keeping adequate security margins in order to take into account, on one hand, approximations inherent in the modelling of unit operations and, on the other, adequate available performance margins, so as to be able to cope with operational conditions that may occur in reality (mainly daily and operational fluctuations of transportation) and that cannot be taken into consideration in simulations. Assumed coefficients of highest use of the turbo compressors are: - Power generated by the turbine equal to 95% of the maximum “on site” power;

22 - Number of revolutions of compressor and turbine (RPM) equal to 100% of nominal revolutions (RPM)

For the purposes of security and reliability of the transportation system, at least one spare unit (or “emergency”) is installed in any plant, which, under normal operating conditions (including the most severe transportation scenarios), is able to replace each of the used units. This also allows for carrying out normal maintenance of the compressor units without interruption or transportation reduction. The number of spare units depends on the number and power of the compressors installed in the plant. For stations with up to three installed units, in general only one unit is kept for emergency (or two units of a lower capacity than those operating, provided that the sum of the respective powers is higher than or equal to the power of each one of the functioning units). In the case of plants with four or more installed units, two units are also kept as spares with a unitary power that is at least equivalent to that of the functioning units.

A further constraint to be considered in plant operations is the range of head and permissible flow rates depending on the characteristics of the installed compressors, defined, in the design phase, in order to optimise the provided service operations. This may materialise in the limitation of the highest delivery pressures even in the presence of capacity available on turbine or, in other cases, in the need to use special couplings of installed units in some operating ranges.

Finally, it is clear that the delivery pressure cannot exceed the highest permissible pressure for the pipeline(s) downstream from compression, as previously explained.

2.4.5 Market scenarios They consist in all user off-takes from the Snam Rete Gas transportation system. For the purposes of defining network performances, these scenarios are defined from time to time so as to take into account the most severe transportation conditions. For the purposes of defining capacities at the Entry Points interconnected with the foreign pipelines, the most severe scenario for importation from Russia and Northern Africa is that of summer, in which as a result of reduced off-takes of the market along the line and of requirements for storage injection, the entry gas volumes must be transported for longer distances. In the case of the Point of Gries Pass, located in the vicinity of important consumption centres, seasonality is less emphasised; the most severe scenario may also be that of winter, as it has been shown by performed hydraulic simulations, since at some junction points of the network, levels of pressure that allow for suitable feeding of pipelines going out from here, must be guaranteed.

23 The choice of reasonably cautious conditions in which to carry out simulations constitutes a security factor. The choice of reference conditions considered to be the most severe guarantees the availability of capacity resulting under other reference conditions even in presence of deviations from these boundary conditions.

Verifications required for definition of the transportation capacities are carried out taking as reference scenarios of off-takes from the network based on the evolution of demand for gas in Italy during the next 10 years.

2.5 Interruptible capacities In the context of establishing firm transportation capacities, the quantity of annual interruptible transportation capacities and seasonal interruptible capacities are estimated for subsequent scenarios, the analyses of interruptible capacities are not very significant, since there is an increasing uncertainty concerning market off-takes and network structures, affected by maintenance operations to be planned, possible cases of unavailability of plants and time schedules for commissioning new reinforcement; therefore analyses are carried out each year only for the next year.

The characteristics of interruptible transportation capacities (annual or seasonal), in terms of the duration of interruptions and procedures for activating them, are published by the Transporter on his web site; a general description of them is given below.

2.5.1 Annual Interruptible Capacities Firm transportation capacities are those resulting from the most severe transportation scenarios that can be foreseen on the network. These quantities are transportable upon the request of the users for whom they are booked at any moment of the year, except in the periods when structural maintenance is carried out. Strictness with which these estimations are carried out, aligned with the standards of the European transportation companies, results from liabilities assumed by the Transporter towards users to guarantee, in some cases also for long period of time, reliable transportation of quantities, object of the contract. In many cases however, effective operation of the network is carried out also with lower pressure values, which are acceptable at the operational level but that cannot be considered as “usual” for “ex ante” determination of capacities that will be booked. Other scenario values, such as for example, disposal on the network, of withdrawals for storage, may also affect estimation.

In these cases, which are, however, situations compatible with normal operations, further transportation capacities, with respect to the firm ones, may appear. In order to estimate these capacities, reference parameters in the hydraulic calculation (typically lowest pressures along the network), which are less

24 restrictive than those used for calculating firm capacities, but that guarantee however suitable security margins, may be used. These capacities may be defined as annual interruptible capacities and have the following characteristics: S Availability is secured unless there are particular events of the network (configuration of off-takes reduced on the whole network or on part of it that affects capacity of transportation for importation; high requests of pressure at some points along the importation line in order to meet higher than expected local market requests or special network configurations). S For given types of possible interruptions that will more likely occur during weekends and holiday periods, or however of lower market off-take (which is usually planned slightly in advance), a few days’ notice can usually be given for interruptions or reductions in the annual interruptible capacity (at weekly planning level).

In some cases (such as importation from North Europe) in which seasonal effects of off-takes on transportation capacities are small, interruptible transportation capacities may be calculated on the basis of an average value of interruptible capacities available during the various periods of the year.

2.5.2 Seasonal Interruptible Capacities There is a second group of interruptible capacities, to be considered as the capacity that could be transported in addition to the annual one, affected by external factors such as variability of off-takes due to climatic conditions, which is why the term “seasonal” is used. During the winter, as a result of a drop in temperature that implies an increase in off-takes, it is indeed possible to inject a higher quantity of gas from the Points of importation without overloading the importation lines themselves to the same extent. As the term used to describe them implies, with interruptible capacities the Transporter reserves the right to reduce the quantity of imported gas, either totally or partially, any time conditions require it, to safeguard the status of the network and operational security, maximising coverage of market demand. To determine these capacities, average capacities of those relating to verifications with standard constraints of the network, similar to those used for calculating firm capacities, and those with constraints similar to those used for calculating annual interruptible capacities are considered. Analyses are carried out with a winter holiday scenario (January). This category of capacities has the following characteristics: S period of availability of this capacity is normally from October to March; S given the type of possible interruptions that are more likely to happen during weekends and winter holiday periods, coinciding with particularly mild weather, normally foreseeable 2/3 days in advance, a few days’ notice can be foreseen for interruptions or reductions in seasonal interruptible capacity

25 2.6 Simulation programs Transportation of gas on the Transporter’s network is checked by hydraulic simulations carried out using special “ad hoc” simulation systems, developed for simulating a meshed network such as the one operated by Snam Rete Gas. For calculating capacities at Entry Points on the National Network interconnected with foreign pipelines, the simulation system called SIRE produced, according to the Transporter’s specification, by the company TEMARS (currently called EniData) of Bologna, which is also responsible for its maintenance and updating, has been used.

2.6.1 The SIRE system The SIRE system is represented by a set of programs aimed at simulating meshed networks and compressor stations (the latter also one at a time and “disconnected” from the network) either under steady or dynamic conditions. Interaction with the system occurs by means of graphical interface that enables both the introduction of data required for the “topological” description of the network and the transportation scenarios to be checked and analysis of simulation results. Main characteristics of system allow for : S “modelling” of the network representing it by sections of network, of length not higher than 50 km, that connect significant points, called “calculation points”; these points correspond, in the model, to physical elements such as main connection points between pipelines, detachment points of shunts or of distribution networks, changes of diameter, important changes of depth profile of pipelines. The “calculation points” are also located at the level of the compressor stations and of injection points in the network from importations or from more important national productions; S simulation of a network for calculation of the following sizes: a) pressure, temperature and composition of gas at all the represented points of the network ; b) flow rate and composition of gas in any section; c) working points of turbines and active compressors and calculation of the main related sizes; d) determination of operational parameters in the special components (plants, valves, importations, wells, storage facilities, off-takes); S concentration of off-takes of gas in the “calculation points”, as well as quantities of gas injected in the network from the inlet points; S resolution of a system of equations related to balances of energy, flow rate, composition and transportation equations according to formulas and models acknowledged by scientific literature and by technical associations for gas; S utilisation of a model related to compressor stations, based on: a) application of the criterion for characteristic control of plant for distribution of flow rate between the units; b) realistic simulation of the working point of compressors and turbines, thanks to the use of a mathematical model that describes effective characteristic curves of the single machines, resulting from field data (where available) or from expected curves (“expected”) provided with by the

26 manufacturers; this simulation allows for determination, with a good approximation, of the working perimeter of stations based on the effective limit curves (antisurge, minimum and maximum number of revolutions, maximum power); c) calculation of sizes of units and plant based the model of units (for example: consumption of gas, power required by the compressor and power supplied by the turbine). In all the models of calculation, the following base main equations are used:

Calculation of pressure drop Equation of Fergusson Equation of status for calculation of Z and deduced factors Equation of Redlich-Kwong Equation of Serghides Calculation of friction factor (Colebrook approximation) Calculation of viscosity Method of Dean-Stiel

2.6.2 Model of network and simulated scenarios For the purposes of transportation verification of the importation capacities, transportation is simulated, under the steady state conditions, on a network substantially coinciding with the National Gas Pipeline Network. In the simulated network some significant sections of the transportation network that are not part of the National Network, whose structures are especially affected by the upstream network structure, are represented. On the contrary, current off-takes and injections of gas, on networks diverted from the simulated network, but not represented here, are taken into account by means of appropriate criteria for “aggregation” that consider structures of the same networks.

2.6.3 Reports The system makes it possible to print the main results in both graphical and alphanumerical form, with respect to flow rates of gas and to performances of the compressor stations. The graphical representation of the network of the natural gas pipelines is schematic but sufficiently correlated to the real geographical layout.

27 3 ATTACHMENTS

28 List of Development Projects NATIONAL NETWORK

Diameter Length Number Power Diameter Length Number Power (mm) (Km) of units (MW) (mm) (Km) (MW) of units Add. Import. Russia:sect. Flaibano-Oderzo 1200 52 Reinf. Transmed: Station of Tarsia 1 25 Add. Import. Russia: sect. Istrana - Camisano 1200 37 Reinf. Transmed: Station of Montesano 1 25 Add. Import. Russia: sect. Bordano-Flaibano 1200 32 Reinf. Transmed: Station of Melizzano 1 25 Add. Import. Russia:sect.Tarvisio-Malborghetto 1200 24 Reinf. Transmed: Station of Montesano - - Add. Import. Russia: sect.Malborghetto-Bordano 1200 45 Reinf. Filters and Measur. syst. of Masera - - Add. Import. Russia: sect. Camisano-Zimella 1400 43 Reinf. Transmed: Nat.gas pipel.Enna-Montalbano 1200 86 Add. Russia: ad. Station Malborghetto - - Reinf. Transmed: Nat.gas pipel.Palmi-Martirano 1200 112 North Europe: new Station of Masera 3 36 Reinf.Transmed: Nat.gas pipel.Campochiaro-Sulmona 1200 94 North Europe: Passo Gries-Mortara 1200 177 Nat.gas pipel.Pontremoli - Parma 900 70 North Europe: adjust. Inst.m Masera & Mortara - - Station of Poggio Renatico (Fe) 3 50 Nat.gas pipel. Gela-Enna 900 67 Nat.gas pipel. Bernalda-Palagiano 1050 7 Reinf. Transmed: Station of Enna - - Connect. storage of Collalto 600 15 (piping) Reinf. Transmed: Station of Messina (reinf.) 2 60 Nat.gas pipel Gagliano-Sparacollo 400 16 Reinf. Transmed: Station of Tarsia - - Reinf. Nat.gas pipel. Alessandria-Oviglio 750 12 Reinf.Transmed: Station of Melizzano (piping) - - Doub. Nat.gas pipel.VE-TN: sect. Vigasio - Sona 500 15 Reinf.Transmed: Station of Gallese (reinf.) 1 25 Reinf. Nat.gas pipel.VE-TN: sect.Bosentino-Trento 400 9 Reinf.Transmed: Station of Terranuova B. (reinf.) 1 12

29 REGIONAL NETWORK Diametro Lunghezza Diametro Lunghezza (mm) (Km) (mm) (Km) Reinf. Industr. Centre of Brindisi 1050 9,8 Raddoppio Mira-Mestre 400 7,1 Natural gas 750 37,5 Raddoppio Deriv. per Pontelongo 200 7,1 Reinf.Nat.gasiliOili pipe 2nd feeding of 750 20,7 Pot. Der. per Vittorio (Tv) 250 6,9 Pot.Met.Bn-CisternaNl Tr. Bn-Piana di M.V. 750 20 Pot. Spina Nord di Casalpusterlengo 200 6,7 Pot. Der.Ne per Bagnoli 750 14,5 Pot. Met. Raldon - Legnago 250 6,5 Pot. Tr. Sergnano-Malossa 750 13 2° Pot.Met. Santerno - Imola 400 6,3 Pot. Der. Sermide:Castagnaro-Bergantino 750 11,7 Pot. Derivazione per Lucera (Fg) 300 6,2 Pot. Bernalda-Altamura: Bernalda-Matera 600 40,1 Ba 11: All. di Castelmezzano (Pz) 100 6,1 Met. Giarratana-Solarino 600 38 All. di Alia (Pa) 100 6 Met. Palaia-Livorno 600 29 Pot.:Coll. Alpignano-Der. per Condove 300 5,9 Pot. Bernalda-Altamura: Matera-Altamura 600 15,8 Cl 8: Dir. per Carpanzano (Cs) 150 5,8 Coll. Der. Lecco al Met. per La Valtelli 600/300 1,6 Cl 2: Der. per (Cs) 200 5,6 Pot. Cherasco - Cuneo (Cn) 500 36 Cl 24: All. di Casabona (Kr) 100 5,5 Pot. Br-Arnesano 1ø/2ø Tr. Br-Trepuzzi 500 26 Dir.Ne per Palermo 250 5,4 Pot. Casaletto - Chiuduno 500 25 Pot. Metanodotto Lurago-Pontelambro 300 5 Met. Gagliano-Capizzi-Sciara Tratto Capizzi-Mistretta (Me) 500 16,5 Cl 22: Der. per Stignano (Rc) 250 4,9 Met. Bz-Bressanone-Brunico 500/300/250 92,7 Pot. Derivazione Manzano-Buttrio (Ud) 250 4,8 Met. Mornico al Serio-Ospedaletto 2° Tr. 500 11,5 Cl 7: All. di Zungri (Vv) 150 4,8 Met. Mornico al Serio-Ospedaletto 1° Tr. 500 11 Pot. Der. Sud Cantu' 250 4,7 Met. Mornico al Serio - Zanica 500 10 Ca 13: All. di S. Nicola M. (Bn) 150 4,5 Pot. Br-Arnesano 3ø Tr. Trepuzzi-Arnesan 500 8,8 Pot. Spina Cava Dei Tirreni 250-200 4,3 Pot. Zanica - 500 3,9 Pot. Der. Castelnuovo - Garfagnana 300 4,1 Der.Ne per Alcamo-Giardiniello E Dir. 400/100 48,1 Ca 15: All. di Baselice (Bn) 150 4 Pot.:Coll. Albano di Lucania-Salandra 300 25 Cl 20: All. di (Cs) 100 4 Met. Triggiano-Locorotondo: 1° Tratto 300 25 Pot. Met. Cesano Maderno-Novara 400 4 Der. Sannicola-Ugento-Tricase: 2ø Tr. 300/250/100 24,4 Ba 1: All. di S. Martino D'agri 100 4 Pot. Rete Umbra: Pietrafitta-Perugia 400 23 Ba 8: All. di Accettura (Mt) 100 3,8 Raddoppio Met. Forli'-Faenza 400 21,7 Pot.Der. per Fabriano E Sassoferrato 150 3,6 Der. Cagnano V.-Carpino: 2ø Tr. 250 21,2 Ca 14: All. di Morcone (Bn) 100 3,6 Met. Triggiano-Locorotondo: 2° Tratto 300 20 Pot.Der. per Varese 300 3,5 Met. Contursi-Battipaglia 400 19,5 Pot. Met. - 300 3,3 Met. Gattinara (Vc) - Prato Sesia (No) 400/200/150/100 18,1 Pot. All. Com. di Montecatini 1ª Presa 300 3,1 Der. Sannicola-Ugento-Tricase: 3ø Tr. 300/150 14,7 Pot. Der.Ne per Suzzara (Mn) 300 3 Pot. Met. Gozzano-Domodossola 200/150 12,9 Pot. Diram. per San Pellegrino 300 3 Raddoppio Deriv. per Tolmezzo 250 11 Pot. Zona Industr. di Vicenza 250 3 Pot.Der.per Riva Del Garda 300 10,9 Pot. All. Comune di Meldola (Fo) 200 3 Pot. Deriv. per Sestri Levante 2° Tratto 400 10 Pot.All.Comune di Alfonsine 150 3 Pot.Met. Mondovi'-Cuneo 400 10 All. Comune di Macchiagodena (Is) 150 3 Pot.Der. per Abbadia Lariana 300 9,9 Metanodotto Meleti - Maccastorna 400 2,9 Pot.:Coll. Carpi-Novi di Modena 300 9,3 Coll. S.P. Clarenza - S. Gregorio 400 8 Met. Settala-Rodano 300 7,4 Pot. Met. Albino - Cazzano Sant'andrea 300 7,8

30 Diametro Lunghezza Diametro Lunghezza (mm) (Km) (mm) (Km) Pot. Der. per Marcon (Ve) 250 2,5 Pot. All. Comune di Monselice 200 0,6 Pot. Met. Vimercate-Muggiò 300 2,5 All. Comune di Montemurro (Pz) 100 0,5 Pot.Der. per Trezzano Rosa 250 2,5 Pot. All. di (Bg) 150 0,5 Pot. Der.Ne per Adria (Ro) 250 2,5 Pot.Spina Nord di Civitacastellana 100 0,4 All. Comune di Scampitella (Av) 100 2,5 All. (Cs) 150 0,4 Pot.Der.per Ozzano-3ª Parte 200 2,3 All. Frasso Telesino (Bn) 100 0,3 Ca 13: All. Campoli Del Monte Tab. 100 2,3 All. S.Vincenzo La Costa (Cz) 100 0,3 Cl 20: All. di (Cs) 100 2,3 Pot.Der. per Albiolo 250 0,2 Pot. Spina di Corchiano 1o Tronco 150 2,2 Pot. All. 1^ Presa Com. di Magenta 200 0,2 Pot. Der. per Pegognaga (Mn) 250 2,2 All. Sant'onofrio (Vv) 100 0,2 Pot.Spina per Dresano 200 2,2 Riclassamento Der.per Nogarole Rocca(Vr) 200 0,2 Ca 13: All. di Apollosa (Bn) 100 2,2 All. Sant Ilario Dello Jonio (Rc) 100 0,2 Pot.Der. per Mozzate 250 2,2 All. (Cs) 100 0,2 Pot. All. Comune di Trani 200 2,1 All. Comune di (Kr) 100 0,2 Pot.:Coll. Der. per Verzuolo-All. Burgo 300 2,1 Pot. Deriv. per Gardone Val Trompia 200 0,2 Pot. Deriv. per Nave-Caino 200 2,1 All. Bucciano (Bn) 100 0,2 Coll. Alim. Nord Mi - Lentate S.S. 300 2 All. (Cz) 100 0,2 Pot. Der. per Mariano Comense 300 2 Pot. All. Comune di Valenzano 150 0,1 Pot.Der. per Lozzolo 200 2 All. Comune di Sant'angelo Le Fratte (Pz 150 0,1 Pot. All. Comune di Lamporecchio Pt 200 2 All. Grimaldi (Cz) 100 0,1 Pot. Der. Concorezzo Nord 200 1,8 All. Comune di Aliano (Pz) 100 0,1 Pot.Spina Z.I.Rovigo 250 1,8 All. (Cz) 100 0,1 Potenziamento Derivazione per Bellusco 200 1,7 All. Forchia (Bn) 100 0,1 All. Durazzano (Bn) 100 1,7 All. Dugenta (Bn) 100 0,1 Pot. Spina Nord di Treviso 200 1,6 Pot. All. Comune di Altamura 200 0,1 All. Comune di Gambatesa (Cb) 100 1,6 All. Platania (Cz) 150 0,1 Pot. Derivazione per (Bg) 250 1,4 All. (Cs) 100 0,1 Pot. Der. per Vanzago 250 1,4 All. Comune di (Kr) 100 0,1 Pot.Spina di Marcon (Ve) 200 1,4 All. Comune di Rocca di Neto (Kr) 100 0,1 Pot.Spina Sud di Crema 200 1,3 All. Comune di Ciro' 100 0,1 All. Nicotera (Vv) 150 1,3 All. Feroleto Antico (Cz) 100 0,1 All. Sellia (Cz) 150 1,3 All. Grotteria (Rc) 100 0,1 Ba 11: All. di Trivigno (Pz) 100 1,3 Pot. All. Comune di Gravina 150 <0,1 Pot.Der.per Piovene Rocchette (Vi) 250 1,2 All. (Cs) 100 <0,1 All. Comune di Sant'arcangelo (Pz) 100 1,2 All. Filogaso (Vv) 100 <0,1 All. Buonabitacolo (Sa) 100 1,2 All. Vaglio Basilicata (Pz) 100 <0,1 Pot. Deriv. per Rossano Veneto 200 1,1 All. Cancellara (Pz) 100 <0,1 Pot. Deriv. per Sestri Levante 1° Tratto 400 1 Pot. All. Comune di Casoria 200 <0,1 Pot. Deriv. per Arzano-Casavatore 200 0,9 Pot. All.Comune di Gaeta 200 <0,1 Pot.Der. per Anzio 3° Tratto Dn 100 150 0,8 N° 146 Allacciamenti Utenze Industriali, Termoelettrici E Civili Pot.All. Pontenossa Spa 200 0,8 Pot. Teleregolazione Rete B. Piem. - - Pot. Spina per S. Giorgio Su Legnano 150 0,8 Nuovo Imp. Riduz. di Robecchetto - - All. Comune di Santa Severina (Kr) 100 0,7 Pot. Imp. Reg. N. 562 "La Stanga" - - All. Pietragalla (Pz) 100 0,7 Pot. Imp. Rid. N. 641 - - Coll. Met. Castano-Buscate E Der. Inveru 200 2,9 Pot.Imp.Rid.N°959 S.Apollinare Q=20.000 - - Pu 30: All. Greci 100 2,8 Pot.Imp.Rid.N°789 Scandicci Sud Q=300000 - - Pot. All. Comune di Pomigliano D'arco 200 0,6 Pot.Imp.Rid.N°98 Fontaniva Q=15000 M3/H - - All. Settingiano (Cz) 100 0,6 Pot.Preriscaldo Imp.Rid.786 Colle V.Elsa - - 31