Active power reserves evaluation in large scale PVPPs

The present trend on investing in renewable ways of producing electricity in the detriment of conventional fossil fuel-based plants will lead to a certain point where these plants have to provide ancillary services and contribute to overall grid stability. Photovoltaic (PV) power has the fastest growth among all renewable energies and managed to reach high penetration levels creating instabilities which at the moment are corrected by the conventional generation. This paradigm will change in the future scenarios where most of the power is supplied by large scale renewable plants and parts of the ancillary services have to be shared by the renewable plants. The main focus of the proposed paper is to technically and economically analyze the possibility of having active power reserves in large scale PV power plants (PVPPs) without any auxiliary storage equipment.
The provided reserves should contribute to the total amount of Frequency Containment Reserves (FCR) required by TSOs, reserves which are released during transients. To realize this PVPPs have to operate below their maximum available power and operate in Frequency Sensitive Mode (FSM). The reserve can also be used to fulfill future grid codes (GCs) requirements such as Power Ramp Limitation (PRL) during high slopes of irradiance.