The following dynamic loss formulas will be used for calculating distribution loss factors beginning in 2007:<br><br> Secondary Delivery Voltage: 1.06102 + ((2.1951 * 10^-10)*(System Load^2)) <br><br> Primary Delivery Voltage: 1.02370 + ((2.4522 * 10^-10)*(System Load^2)) <br><br> High Delivery Voltage: 1.00816 + ((1.0086 * 10^-10)*(System Load^2)) <br><br> In these formulas, System Load represents the load for the Ameren Illinois service territory.

Since the start of the MISO "Day 2" market on April 1, 2005, transmission losses have been calculated dynamically. By “dynamically”, we mean that they change each hour depending on the load in, and the flows through, each Control Area.<br><br> Through the end of November 2006, transmission losses were calculated separately for each of the three Ameren Control Areas (AMRN, CILC, and IP). However, since Ameren reconfigured its Control Areas, MISO changed the way that transmission losses are calculated. <br><br> During a brief transition period from December 1, 2006 through February 28, 2007, MISO calculated transmission losses separately for each of the four Ameren companies (UE, CIPS, CILCO and IP). Then, beginning March 1, 2007, MISO began calculating transmission losses for the Ameren-MO (AMMO) control area and for the Ameren-IL (AMIL) control area. <br><br> For more information on how transmission losses are calculated, please contact MISO.