Requirements for Suppliers in AMIL and AMMO

March 2008

Planning Requirements

1)Suppliers must identify to the AMIL or AMMO Balancing Authority (BA) the “steel-in-the-ground resources” that are designated network resources for their load. The suppliers shall provide copies of the Midwest ISO (MISO) Module E to the Balancing Authority at least yearly as required by MISO and must provide updates to MISO with copies to the Balancing Authority whenever network resources change, either in source or magnitude. (This requirement will continue to apply if AMIL and AMMO become Local Balancing Authorities if the Midwest ISO (MISO) is assigned some BA functions as is contemplated with an ancillary services market.)

2)If Supplier’s designated network resources are external to the MISO market, firm transmission must be in place for delivery to the MISO market and corresponding service must be in place through MISO for deliverability to AMMO or AMIL. If Supplier’s identified resources are internal to the market, the units must be deliverable to their load.

3)AMMO and AMIL are members of the Southeastern Electric Reliability Council (SERC)-Gateway sub-region. Absent, a Planning Reserve Study (PRS), SERC-Gateway has a default planning reserve margin (PRM) requirement of 1.15. However, the Midwest PRS Group (of which AMMO and AMIL are members) has established a PRM of 1.143 for 2008 based on a study of the entire PRS region. As such, suppliers’ identified capacity resources must be equal to, or greater than, 1.143 times the projected monthly peak of their load in compliance with those requirements.

4)The Supplier shall provide the Balancing Authority (or LBA) a list of its capacity resources that are designated to serve the Suppliers obligation of 1.143 times their forecasted load for that month. This notification should occur no less than one business day prior to the start of any month in which the supplier’s load obligation has changed or its resources are different than projected in previous Module E submissions.

Day Ahead and Real Time Requirements

1)Suppliers’ identified capacity resources must be offered into the MISO market for each operating day, both in the Day Ahead and Real Time markets, in which they are physically capable of supplying energy. This must-offer requirement includes the provision that the offers must reflect the entire “designated” capacity of the unit(s) to the extent available. (If the identified resources consist of a fractional share(s) of a unit, the offer must be made for the fractional share.) This must-offer requirement comes fromMISO tariff requirement, Module E.

2)Suppliers must at all times have sufficient capacity to cover their load obligation. This includes sufficient capacity in the Day Ahead to cover 100% of the peak load for the operating day. In Real Time, sufficient capacity must be available to cover the actual load of the supplier at all times. Units that are offered into the Day Ahead market that do not get committed or dispatched in Real-Time but remain available, continue to count as capacity. Load obligation is defined to be the value provided by the AmerenTransmissionServicesBusinessCenter based on the supplier’s obligations as a BGS and/or RES or independent load serving entity.

3)When a Suppliers’ identified resources are unavailable, or when their load obligation exceeds the identified generation resources, Suppliers must purchase capacity,or identifyadditional capacity to which they have rights, to cover their load obligation. The replacement capacity must meet the same deliverability requirements as in 2) above. This obligation for capacity to meet or exceed load applies in the Day-Ahead and in Real-Time.

4)Replacement (or additional) capacity in the Real Time secured through units in the MISO market must have Real Time Offers in place as soon as MISO market rules permit after the purchase has been arranged but in no case later than the start of the second operating hour. Replacement capacity outside of the MISO market must have an energy schedule (tag) approved and flowing as soon as capacity has been arranged (following the guidelines for energy tagging) in order to count towards load sufficiency. Failure to secure, or identify, enough capacity to cover the load obligation shall mean the Supplier will be designatedto be in default.

5)When the AMIL or AMMO Balancing Authority Operator determines that load has exceeded forecast such that a capacity deficiency is in effect, or whenever a designated resource is not available such that a capacity deficiency is in effect, the AMIL or AMMO BA Operator will notify the Supplier of the deficiency. This correspondence is expected to consist of a phone call and either email or fax. The Supplier will have 30 minutes to identify other capacity, or purchase replacement capacity, to cover their load obligation. After securing replacement capacity, the Supplier shall notify the AMIL or AMMO BA Operator of the specifics of that replacement capacity including the specific unit (or system if outside the MISO market), the MW amount, and the transmission reservation number as necessary.

6)If Supplier serves only loads that can be identified on the transmission system and can be interrupted during capacity shortages without subjecting other loads to interruption, Supplier’s load will be designated to be shed following directive from the MISO RC or as determined by the Ameren Transmission Supervisor for reliability reasons. For a Supplier whose load is commingled with other Supplier’s loads, the Balancing Authority will arrange for the purchase of the necessary capacity for which the Supplier will be financially responsible.

7)For both Day Ahead and Real Time, the Supplier shall notify the AMIL Balancing Authority (or LBA) whenever its designated capacity resources change, either in CPnode or MW amount, from that provided in section 4 – Planning Requirements.

General Requirements

1)Suppliers shall provide a list of voice, facsimile, and email contacts to the AMIL or AMMO Balancing Authority (or LBA) for resource adequacy issues. These contacts are expected to be 24-hour contacts that can address capacity issues as described above.

2)Suppliers shall notify the AMIL and AMMO BA Operators of real time issues by phone call at 314-554-2998.