The Midcontinent Independent System Operator (MISO) on July 11 submitted to the Federal Energy Regulatory Commission what is in essence a retirement schedule for the coal-fired E.D. Edwards Unit 1 in Illinois.
FERC is being asked to approve an unexecuted System Support Resource (SSR) between Ameren Energy Marketing and MISO. The SSR Tariff provisions permit MISO to determine compensation for selected generation resources where a market participant desires to retire or suspend operation of a facility but MISO determines that the facility is needed to maintain system reliability.
Market participants must submit an Attachment Y notice to MISO at least 26 weeks in advance of any plan to retire or suspend operation of a generation unit or a synchronous condenser unit. Based upon information submitted by the market participant, and MISO’s knowledge of grid conditions, MISO determines if the facility should be designated as an SSR Unit. The costs pursuant to an SSR agreement generally are assigned to the entities serving load in the affected control areas (i.e., Load Serving Entities or LSEs).
Edwards Unit 1 is a 90-MW coal-fired steam boiler located in Bartonville, Ill. Edwards 1 began service in 1960.
In August 2011, Ameren submitted an Attachment Y notice to MISO to suspend Edwards 1 as of Feb. 6, 2012 for a period of 36 months. On Dec. 12, 2012 Ameren submitted a revised Attachment Y notice to MISO to retire Edwards 1, effective Dec. 31, 2012. MISO, in collaboration with Ameren Transmission Co., completed an analysis of the retirement of Edwards 1.
MISO then told Ameren that Edwards 1 would be designated an SSR unit until such time as appropriate alternatives could be implemented to mitigate reliability issues. The analysis concluded that the proposed retirement of Edwards 1 would result in violations of specific applicable Ameren Transmission planning criteria during the summer and shoulder peak load periods until the completion of transmission reinforcements that include the 345-kV Maple Ridge-Fargo line and Maple Ridge Substation. As a result, MISO designated Edwards 1 an SSR unit until such time as appropriate alternatives can be implemented to mitigate reliability issues.
MISO began working with Ameren and the MISO Independent Market Monitor (IMM) to negotiate an appropriate SSR agreement. A draft SSR was developed between MISO and Ameren for a period of 12 months beginning on Jan. 1, 2013. Ameren has continued operating Edwards 1 through the present time.
A planned transmission upgrade that, after completion, would enable Edwards 1 to retire is proposed in the MISO Transmission Expansion Plan 13, subject to approval by the MISO Board of Directors in December 2013. The completion of this transmission upgrade will resolve the need for Edwards 1 to be designated as an SSR unit. Until this alternative solution is completed, however, Edwards 1 will be required for system reliability, and the SSR agreement is necessary to ensure continued system reliability.
Although MISO expects that the Edwards 1 will continue as an SSR unit until the Maple Ridge–Fargo 345-kV transmission project is completed in December 2016, other alternatives will be sought in considering the annual renewal of the SSR agreement.
MISO currently believes that the subject SSR agreement may be required for at least the twelve-month term ending Dec. 31, 2013, and it anticipates entering into a subsequent SSR agreement with Ameren for the period from Jan. 1, 2014 until the completion of the Maple Ridge–Fargo 345-kV project in December 2016.
The Edwards plant began commercial operation in 1960. Edwards Unit 2 (240-MW net) began commercial operation in 1968, while Unit 3 (315-MW net) began commercial operation in 1972. Units 2 and 3 are not involved in this retirement deal.