the LOR1 threshold (in MW) see paragraph (d). – The LOR2 threshold within the LOR assessment horizon is MAX (LCR, FUM). The LOR1 threshold within the LOR assessment horizon is MAX (LCR2, FUM). Schematic representation of LOR Formulation in circumstances of extreme FUM values UNCERTAINTY MEASURE See also Appendix A for more detail. Forecast regional excess supply (RXS) The following forecasts and measurements in each region for the LOR assessment horizon will be assessed in determining the value of RXS: available capacity of scheduled generating units (A); unconstrained intermittent generation forecast (B); and Operational Demand (C). Forecast RXS for any time in the LOR assessment horizon is determined by the formula A + B C. – Determining RXS error distribution RXS Error = Forecast RXS Actual RXS for a particular forecast and a point in time. – AEMO collects, stores and updates historical statistical data on RXS error, in different power system, ambient weather and other relevant conditions. At the time of assessment, AEMO applies the historical data and the conditions expected for the relevant period in the LOR assessment horizon, as illustrated in Appendix A, to determine a distribution of error (RXS error) across all forecasts within the first 72 hours of the LOR assessment horizon. The input states that will be taken into account in developing the distribution will be: forecast lead time; forecast regional reference node temperatures; current demand forecast error for forecast lead times below 8 hours; and unconstrained intermittent generation forecast. Forecast uncertainty measure (FUM) calculation The FUM for a region, point in time and set of expected conditions, is the number of MWs representing the quantity of RXS for which AEMO determines a specified confidence level of the RXS error not exceeding that number of MWs. Confidence levels are determined in accordance with clause 3.4 and are set out in Appendix B. FUM will be determined using the RXS error for the first 72 hours of the LOR assessment horizon. For the remainder of the assessment horizon a static value will be used for FUM as set out in clause 3.6.
the LOR1 threshold (in MW) – see paragraph (d). The LOR2 threshold within the LOR assessment horizon is MAX (LCR, FUM). The LOR1 threshold within the LOR assessment horizon is MAX (LCR2, FUM). Schematic representation of LOR Formulation in circumstances of extreme FUM values UNCERTAINTY MEASURE See also Appendix A for more detail. Forecast regional excess supply (RXS) The following forecasts and measurements in each region for the LOR assessment horizon will be assessed in determining the value of RXS: available capacity of scheduled generating units (A); unconstrained intermittent generation forecast (B); and Operational Demand (C). Forecast RXS for any time in the LOR assessment horizon is determined by the formula A + B – C. Determining RXS error distribution RXS Error = Forecast RXS – Actual RXS for a particular forecast and a point in time. AEMO collects, stores and updates historical statistical data on RXS error, in different power system, ambient weather and other relevant conditions. At the time of assessment, AEMO applies the historical data and the conditions expected for the relevant period in the LOR assessment horizon, as illustrated in Appendix A, to determine a distribution of error (RXS error) across all forecasts within the first 72 hours of the LOR assessment horizon. The input states that will be taken into account in developing the distribution will be: forecast lead time; forecast regional reference node temperatures; current demand forecast error for forecast lead times below 8 hours; and unconstrained intermittent generation forecast. Forecast uncertainty measure (FUM) calculation The FUM for a region, point in time and set of expected conditions, is the number of MWs representing the quantity of RXS for which AEMO determines a specified confidence level of the RXS error not exceeding that number of MWs. Confidence levels are determined in accordance with clause 3.4 and are set out in Appendix B. FUM will be determined using the RXS error for the first 72 hours of the LOR assessment horizon. For the remainder of the assessment horizon a static value will be used for FUM as set out in clause 3.6.