Once MISO provides a Start Instruction, MISO’s Unit Dispatch System (UDS) validates the Resource meets the following two requirements before it will send a dispatch signal: 


  1. Resource must have their output breaker closed; or, more accurately, have indications that it is closed. 

  • As a result, the MISO State Estimator breaker status will solve as if it is closed. 

  1. Resource must have an absolute value of MWs in excess of 0.5MW. 

  • EXCEPTION: All Dispatchable Intermittent Resources are considered online anytime the state estimator breaker status indicates closed. 

  • Usually, 0.5MWs is enough to allow the MISO State Estimator to solve MWs at the Resource.  Occasionally, minor residual errors between the MISO EMS Model and the Bulk Electric System, result in the need for additional MWs (>0.5MW) before the MISO State Estimator solves for a MW output on the Resource. 


Note: Ideally, the Resource will send MISO a non-zero Control Mode, but it isn’t a requirement before the UDS considers the Resource as online. 


MISO’s Security Constrained Economic Dispatch (SCED) algorithm runs every five minutes to develop Resource Dispatch Targets for the end of the next dispatch interval. As a result, the system may not recognize the new Resource in the current or even the next case, resulting in a dispatch signal delay for up to 15 minutes.   


MP’s should anticipate that if their Resource came online at a 00:00, then they should expect to see their first Dispatch Targets to show up at between 00:05 and 00:15. 


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