The security of the electric system

Ensuring the security of the national electric system and contributing to the security of the countries with which Italy is interconnected are sensitive tasks, which Terna performs through a series of actions governed by scrupulous risk assessment. The objectives are to reduce the probability of service interruption to a minimum and to contain the consequences as much as possible when it does happen.

Terna uses security criteria that are in line with the best European practices in the management of interconnected electricity systems.
These practices are the result of the cooperation that has existed for some time in the international organisations in which Terna participates in its capacity as a Transmissioni System Operator (TSO). In particular, it is a member of the ENTSO-E, the most significant organisation, which was founded in 2009 to replace the international associations ATSOI, BALTSO, NORDEL, UCTE, UKTSOA, and ETSO. The TSOs collaborate in writing reports on the security and adequacy of the European electricity system. They also collaborate in drawing up a ten-year Developmenti Plan for the European electric grid.

In order to maintain a high level of security, Terna’s performance of its role has to be excellent in all phases of its activity, from the development, construction, and maintenance of infrastructure to its operation in real time.

In particular, preventing and containing operational risk means that Terna must physically protect its infrastructure, prepare defence plans to limit interruptions, and carry out advance planning for real-time operation and control. To make all of that possible, Terna invests in the training of its workers, using modern means of simulation that reproduce the system’s behaviour as it would be observed from the control rooms.

Terna’s commitment to continual improvement is shown in the Electric System Security Plan drawn up by the Company and approved by the Ministry for Economic Development. Required by law after the black-out in 2003, the Plan is prepared every year and has a three-year horizon. Developed and coordinated entirely by Terna, the Plan is a reference point for corporate planning and constitutes an increasingly important commitment, as demonstrated by the growth of investment from €10 million in 2004 to €74.5 million in 2009.

Perusing the six Plans drawn up since 2003, one can observe the gradual evolution of the concept of electric system security developed by Terna. Initially, the main need was to enhance anti-black-out measures, but in the following years the approach became more systematic and included the strengthening of the Company’s disaster-recovery capability and the physical protection of the infrastructure from intentional external attacks.

Overall, these six editions of the Plan anticipate control concepts adopted by modern theories of smart grids. In particular, the Company constructed the widest area monitoring system, called WAMS, in Europe and system protection models that react to malfunctions by adapting to the particular network conditions. In 2009, numerous accidental failures occurred on the grid, but the effectiveness of the systems adopted enabled the system to avoid critical consequences.

In 2009, Terna continued to make improvements in:

  • the reduction of the risk of interruptions, thanks to integrated maintenance planning;
  • the real-time control of congestion, thanks to the introduction of techniques of optimal power flow;
  • the automatic control of congestion between the Northeast and Northwest zones of the electric system;
  • the reduction of vulnerabilities, with the going into operation of the Security Operationi Centre, which constantly monitors the physical security of assets, as well as IT security;
  • the gradual extension of the anti-intrusion network and the video surveillance of electric stations;
  • the integration of the defence system with the system of remote control of distributors, which makes the continuous control of the load available for disconnection in emergencies flexible.

The sixth edition of the Security Plan for 2009-2012 includes €190 million of capital expenditure