301 



through restricting the DSI load. Plant delay reserves protect the 

 reliability of the system against construction delay and poor performance of 

 new and existing plants through second quartlle restriction rights. 



To avoid double counting reserves, the quartlles were categorized based 

 on the reserves they predominantly provide. Since BPA does not plan or 

 acquire resources to serve the first quartlle under the terms of the power 

 sales contract, the first quartlle offers only operating and stability 

 reserves. The Interruptlblllty of the DSI first quartlle Is recognized In the 

 character of service adjustment of the 7(c)(2) margin study. The second, 

 third, and fourth quartlles provide capacity for both stability and forced 

 outage reserves. However, since the fourth quartlle can only be restricted 

 for 15 minutes at any one time, this quartlle was not assigned a value for 

 forced outage reserves. Thus, only the capacity associated with the second 

 and third quartlles was valued for forced outage reserves, whereas the 

 capacity associated with the fourth quartlle was assigned a value for 

 stability reserves. Since the second quartlle of DSI load may be restricted 

 for plant delay reserves, the value for plant delay reserves Is based on the 

 energy associated with the second quartlle. The reserves provided through 

 BRA'S restriction rights are valued according to expected use In conjunction 

 with the provisions contained In the power sales contracts. Thus, a 

 determination Is needed of the reserve level in the test year and the amount 

 of reserves provided through the restriction rights on the DSI load. 



The organization of this discussion follows the steps used in valuing 

 the reserves. First, the total required level of Federal system reserves for 



A-3 



