Ancillary Services

Ancillary services (AnS), a tool for the provision of system services (SyS), are defined as services provided by natural or legal persons for maintaining power system operation and the high quality and security of electricity supply. AnS allow any imbalance between electricity consumption and generation to be corrected by means of demand- or supply-side changes.

Those users of the power system (PS) who comply with the relevant technical and commercial terms and conditions set out by the transmission system operator (TSO) have the right but not the obligation to offer AnS at market prices. A non-discriminatory and transparent approach towards all transmission system (TS) users is applied when selecting AnS providers.