Flexible ramping constraint

Implementation of a new flexible ramping constraint in the market optimizations will help ensure sufficient ramping capability is available to meet conditions in the five-minute market interval when conditions have changed from the assumptions made during the prior procurement procedures. Enforcement of the constraint can produce opportunity costs for resources that resolve the constraint. Through this initiative the ISO and stakeholders will address how to appropriately compensate resources that resolve the constraint.

Outcome

Board of Governors decision:  August 25, 2011
FERC Order date:  December 12, 2011
Implementation date:  December 13, 2011

The ISO implemented a new flexible ramping constraint in the five-minute market optimization as an interim measure until market bid-based products are developed through the Flexible Ramping Product initiative.  Resources that resolve a constraint are compensated at the shadow price, which is the marginal unit’s resource specific opportunity cost.

FERC filings and orders

Policy development

Tariff development

Implementation