Relations with companies using the electricity service


Terna mainly deals with companies operating in the electricity industry and belonging to one or more of the following categories:

  • owners of grid segments, to which Terna must guarantee the right to connection in compliance with regulatory and technical provisions;
  • dispatching users, i.e. producers, end customers, or wholesalers with which Terna regulates the dispatching service;
  • interruptible customers, i.e. end customers of withdrawals that grant Terna the right to interrupt their load;
  • distributor companies and owners of production plants, with which Terna regulates the electricity transmission service along its grid.

Relations between the industry companies and Terna are mainly regulated by the industry Authorities and are defined technically and commercially in the Grid Code.

In particular, with regard to the dispatching service, Terna regulates with the users of the injection dispatching service the economic items regarding the procurement of the resources necessary to safeguard the security of the national electricity system, thus maintaining a balance between injections and withdrawals, as well as ensuring that grid parameters, such as voltage and frequency, are at their appropriate levels.

EU3The economic items regarding procurement on the dispatching service market (“MSD”) and imbalances for injection users are negative and in 2011 amounted to nearly 1.2 billion euro.

With the users of both injection and withdrawal dispatching, Terna regulates the economic items regarding imbalances, understood as the difference between the plans the users presented on the electricity markets and the actual value of the electricity injected or withdrawn.

The economic items regarding imbalances for withdrawal users, including the invoicing of system charges, are positive and in 2011 amounted to nearly 2.4 billion euro.

The most important interactions with electricity companies are managed through My Terna portal, which is the sole channel of access for all the services dedicated to the electricity companies, such as master data management – so that the portal is supplied through the data managed by the Gaudì system (see following box) – connection requests to the NTG, contracts stipulated for dispatching, the management of contacts and viewing the operator’s main data.

It includes a front office and a back office controlled with a single instrument that enables processes to be traced and the progress of paperwork to be monitored, following an e-ticketing logic.

In 2011, Terna procured resources for the interruptibility and instant-load-reduction services aimed at making the functioning of the national electricity system secure in the event the resources procured on the market turned out to be insufficient. There were nearly 170 assignees of the interruptibility and instant-load-reduction services in 2011, with nearly 4,362 MW of power, and the related negative economic item amounted to nearly 650 million euro on an annual basis.

Relation with Terna of companies operating in the electricity industry - Number of companies


2011 2010 2009
Interruptible users (1) 171  154 134
Distributors directly connected to the NTG 20 19 19
Injection dispatching users (Producers and traders) 91  86 77
Withdrawal dispatching users (Traders and end customers including Single Buyer)  110  109 106
(1) Beginning in 2011 these also include the assignees of the instant-withdrawal-reduction service.

Master data of electricity production plants started

In 2011, Terna was involved in initiating and implementing the Gaudì system (plant master data management).

The system, whose creation was planned by specific provisions issued by the Electricity and Gas Authority, allows transmitting all master and technical data of the plants and of the electricity production units. The purpose is to centralize within the transmission system operator the master data of all the production initiatives implemented and in progress across the national territory, independently of plant size and type, ensuring the constant update of information. In particular, the Gaudì system attributes a code to each production plant that allows uniquely identifying the plant by all the bodies that operate in the electricity system and that, each one for its own purposes, establish contact with the plant (i.e., Terna or the distributors for connection purposes, the GSE for any incentive purposes, Terna for dispatching activities purposes, etc.).

This centralized platform also organizes the information flows among the various bodies that operates in the sector with the objective of avoiding the duplication of information reports required for the operators.

Effective as of January 2011, Gaudì was created by integrating three principal master data archives managed by Terna: CENSIMP for conducting a census of the plants, RUP relative to the master data of the Significant Production Units(1) and UPN6 relative to the master data of the non-relevant Production Units.

With subsequent releases scheduled during 2012, the system will be further updated with new functions principally aimed at implementing a control dashboard capable of monitoring the sequence of activities involving the access to the production plants system: from the plant’s “physical” connection up to the injection of energy produced into the grid.

The various bodies that operate in the electricity system will be called to contribute, each one according to field of activities, to the master data validation process in order to create transparent access of the electricity production plants to the system services.

(1) Significant production units are the production units with a total production power of the associated generation groups no lower than 10 MVA.