Transelectrica SA is the only operator providing the services of electricity transmission, operational technical management of the Romanian Power System and electricity market administration (by means of its legal personality subsidiary OPCOM SA), such domains being considered as a natural monopoly under the law.

Transelectrica SA carries out these activities under the license that ANRE has granted it, charging regulated tariffs that allow a non-discriminating and fair access of all market participants to the electricity transmission grid, with no additional revenues from other activities.

Transelectrica’s main revenue-producing activities are as follows:

Electricity transmission service
Operational-technical management of the RPS (system services)
Market management service (through the subsidiary OPCOM SA)

This service consists mainly in providing the transmission of active electricity between two or more points of the transmission grid belonging to the RPS, while observing the continuity, safety and quality norms.
The transmission service is a public one according to the transmission and dispatching licence, and the Company has to provide it under non-discriminating conditions for all grid users.
All license holders that input and respectively take out electricity into / from the electricity transmission grid, including for their import/export activities, are the end-users of the electricity transmission service. The transmission service that Transelectrica performs means providing the technical conditions and keeping the operational parameters of the transmission grid when electricity is input in/taken out from it.
The amount of electricity for which the transmission service is provided is that the end-user of the transmission system introduces into/takes out from the electricity transmission grid nodes.
ORDIN nr.44/20.12.2006

Contractul-cadru pentru prestarea serviciului de transport, a serviciilor de sistem şi serviciilor prestate de operatorul comercial participanţilor la piaţa angro de energie electrică, între C.N. Transelectrica S.A. şi [Client]


Transelectrica’s task is to keep the Romanian Power System operating uninterruptedly under safe conditions while observing the quality standards provided in the Grid technical code. To this effect the Company uses its own resources called functional system services and purchases technological system services from the electricity generators.
Transelectrica SA provides this services under two regulated tariffs applied to the same base (electricity purchased by suppliers / eligible consumers):

• tariff for system services, of which
• tariff for functional system services

The Company is also using the mechanisms of the balancing market with a view to balance the output to the consumption in real time.

Functional system services
Functional system services refer to the dispatching ones that Transelectrica provides and they consist in planning and operationally managing the RPS, as well as the other activities of Transelectrica with a view to balance in real time the output and the consumption in order to cover safely the power consumption with minimum operation costs and a good operational safety of the RPS.

To carry out such services the Company allocates its own resources consisting of:

• human resources engaged in this process, usually hired with the UNO DEN
• the operational-technical management infrastructure for the RPS that is the EMS SCADA and the telecommunication, tele-management, protection and control systems. The Company is running specific investment programmes in order to develop all these systems.

Technological system services
These services are purchased from producers under contract upon Transelectrica’s request with a view to maintain the operational safety of the RPS and the quality of transmitted electricity to the parameters from the applicable norms..
Their main components are:

• The primary frequency control reserve (defined as the decentralised automatic control with a static characteristic, distributed by a large number of generating units ensuring the fast correction (within 30 seconds at the most) of the differences between production and consumption at a frequency close to the preset value).
• The frequency-power secondary control reserve (defined as the centralised automatic control of frequency (exchange power with frequency correction) in order to bring frequency / exchange power to the preset values within 15 minutes at the most.
• The power reserve corresponding to the tertiary control:
  • the fast tertiary reserve (the power reserve provided by generating units that are qualified to make the load synchronisation and charging in maximum 30 minutes).
  • the slow tertiary reserve (defined as the power reserve provided by generating units with a start-up and load takeover time smaller than 7 hours).
• Voltage control by means of reactive power;
• The capacity to provide the startup servie to restore the RPS;
• Active energy to cover the losses within the electricity transmission grid.

Transelectrica SA purchases the technological system services from the electricity generating companies under a procedure regulated by ANRE. In practice Transelectrica re-invoices the entire amount of system services purchased from producers (except for the active energy component covering the grid losses) to the ANRE-licensed electricity suppliers that benefit of such services in the end.



Transelectrica SA provides the market management service through OPCOM SA, the revenues of such service being equal to the costs under the contract concluded with this subsidiary. The end-users of the market administration service are the electricity suppliers.