305 



5. SAM currently does not expllcUly model DSI restriction rights 

 for poor performance of existing facilities or delay of conservation 

 resources, because the region Is still working on modeling these restriction 

 rights. For purposes of valuing BPA's right to restrict the DSIs' second 

 quartlle for poor performance, a portion of the firm load curtailments shown 

 In SAM Is assumed to be caused by poor performance of existing Federal thermal 

 plants. To approximate OSI Interruption for poor performance, firm load 

 curtailments In each of the seven years in the planning horizon were 

 multiplied by the following ratio: 



15 percent of Federal thermal resources * 5 percent of Federal hydro resources 

 15 percent of total thermal resources + 5 percent of total hydro resources 



A weighted average of hydro and thermal resources Is used to measure poor 

 performance reserves In recognition of the potential poor performance by both 

 resource types. 



The expected restriction of the DSIs' second quartlle during the 

 7-year planning horizon due to plant delay and poor performance Is summarized 

 In the following table. 



A-7 



