SASKPOWER OPEN ACCESS TRANSMISSION TARIFF

SASKPOWER OPEN ACCESS TRANSMISSION TARIFFATTACHMENT HCurtailment ProceduresWhen system conditions change due to such events as the loss of a transmission line or agenerator, the TRM for the constrained interfaces may increase. The resulting new value of theATC for the interface may be lower than the actual flow through the interface and a curtailmentwill be necessary to bring the flow down to a level that does not exceed operating limits.Curtailment is necessary to restore the operating reliability of the system so that it can withstandthe next single contingency.Curtailment is done with respect to:1. Non-discriminatory treatment of all transmission customers including domestic load.2. Lower priority recallable class service is curtailed ahead of non-recallable 3 class service.3. Rank within the recallable 4 class (longer reservations out rank shorter reservations) isrespected.4. Equal rank recallable service is curtailed on a last in first out (LIFO) basis.5. Non-recallable service is curtailed pro rata in proportion to the contribution each serviceis making to the security limit violation.3 OASIS Non-recallable transmission service is equivalent to SaskPower OATT firm transmission service.4 OASIS Recallable transmission service is equivalent to SaskPower OATT non-firm transmission service.Page | 136