Network Code on System Operation

Title 5 


Ancillary services 


Article 108 
Ancillary services 


1. Each TSO shall monitor the availability of ancillary services.

2. With regard to active power and reactive power services, and in coordination with other TSOs where appropriate, each TSO shall:

(a)  design, set up and manage the procurement of ancillary services; 


(b)  monitor, on the basis of data provided pursuant to Title 2 of Part II, whether the level and location of available ancillary services allows ensuring operational security; and 


(c)  use all available economically efficient and feasible means to procure the necessary level of ancillary services. 


3. Each TSO shall publish the levels of reserve capacity necessary to maintain operational security. 


4. Each TSO shall communicate the available level of active power reserves to other TSOs upon request. 


Article 109


Reactive power ancillary services 


1. For each operational planning timeframe, each TSO shall assess, against their forecasts, whether its available reactive power ancillary services are sufficient to maintain the operational security of the transmission system. 


2. In order to increase the efficiency of operation of its transmission system elements, each TSO shall monitor:

(a)  the available reactive power capacities of power generating facilities; 


(b)  the available reactive power capacities of transmission-connected demand facilities; 


(c)  the available reactive power capacities of DSOs; 


(d)  the available transmission-connected equipment dedicated to providing reactive power; and 


(e)  the ratios of active power and reactive power at the interface between transmission systems and transmission-connected distribution systems. 


3. Where the level of reactive power ancillary services is not sufficient for maintaining operational security, each TSO shall:

(a)  inform neighbouring TSOs; and 


(b)  prepare and activate remedial actions pursuant to Article 23.