2015 Summer Shoulder-Peak Near-Term Assessment of Transmission System Performance ~ Board of Directors Meeting September 30, 2010 Presented by Jeff Mitchell

Sept. 30, 2010Board Meeting2 Near-Term Transmission Assessment Conclusion: The transmission system within the ReliabilityFirst footprint is planned to perform well over a wide range of operating conditions for the 2015 summer shoulder-peak conditions. Observation: Identified constraints are similar to those that are experienced in present day operations, either during shoulder operations, when particular generators are off-line; or particular pumped storage units are in pumping mode.

Near-Term Transmission Assessment Sept. 30, 2010Board Meeting Summer Shoulder-Peak Assumptions: Wind generation modeled at 90% of nameplate, which is slightly above the upper limit of observed actual wind generation output Pumped storage modeled in pumping mode System load level modeled at 55-65% of summer peak

Near-Term Transmission Assessment Sept. 30, 2010Board Meeting4 Location of Wind Generators Study AreaGeneration (MW) PJM East481 PJM South0 PJM West1351 PJM_NI2181 WUMS1391 LAKES414 MISO South0 MRO7715 SERC225 Location of Modeled Wind Generators The majority of wind generation is in the west (MRO, PJM_NI, WUMS, PJM_W)

Sept. 30, 2010Board Meeting5 Near-Term Transmission Assessment Thermal analyses included: 1.Loading under system normal (NERC Category A) and first contingency (NERC Cat. B) conditions 2.Loading under system normal (NERC Category A) and first contingency (NERC Category B) conditions for changes in generation dispatch 3.Ability of the transmission system to support simulated non-simultaneous power transfers in many directions 4. Generation re-dispatch analysis 5. FCITC analysis of pass-through transfers 6. FCITC analysis of source transfers

Sept. 30, 2010Board Meeting6 Near-Term Transmission Assessment Each of these constraints can be mitigated to varying degrees with the re-dispatch of wind or fossil generation Identified Transmission Constraints

Sept. 30, 2010Board Meeting7 Near-Term Transmission Assessment No low voltages under the following conditions: - Base case - First contingencies - Increased transfers - Power-Voltage curves for transfers

Sept. 30, 2010Board Meeting8 Near-Term Transmission Assessment Transfer Scenario FCITC Without Redispatch (MW) Test Transfer (MW) Decreased Generation in Export Areas (MW) Increased Generation In Import Areas (MW) New FCITC (MW) Northwest to LAKES WUMS to RFC West Northwest to PJM West North to PJM NI MRO to RFC West Midwest ISO to PJM West Far West to PJM East MINN to RFC West MISO to PJM West to PJM NI IOWA to RFC West Northwest to PJM East SPP to RFC West Summary of Re-dispatch Analysis

Sept. 30, 2010Board Meeting9 Near-Term Transmission Assessment Suggestions for Improvement to Similar Future Studies of This Type: - Difficulty of converting a Summer model to Shoulder-peak conditions: - Interchange - Generator dispatch - Capacitors in-service & whether switched - Perform high voltage analyses

Sept. 30, 2010Board Meeting10 Near-Term Transmission Assessment Action Today Reliability Committee unanimously endorsed the report on its September 2 conference call. *** Request the Board of Directors approve this report for public distribution. *** Thank you!