Contributions to Tertiary Reserve Requirements under Operating Conditions and Uncertainties

The continuous penetration rising of intermittent generation and the demand growth force the TSO to determine suitable reserve requirements to mitigate contingency in real time operating conditions. These energy reserves are provisioned in Ancillary Service Market and delivered in real time to correct load and renewable energy sources forecasting errors or to overcome equipment outages. A further uncertainty barely involved in the reserve definition is the load variation during the hours of daily ramp or deramp condition, determining the advance or delay of the electrical demand forecast. In this paper, a procedure for evaluating the tertiary reserve requirements deriving from renewable and load uncertainties and power plant unexpected outage is proposed. Furthermore, the seasonal influence on the uncertainties and operating condition are taken into account, as well as the occurrence probability of a combination of several uncertainties.