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otherwise could have been used to import energy purchases. Curtailment can 

 also refer to those measures used to bring resource output in balance with load 

 when there is an operating year energy shortage on a system. 



Curtailment results in an organized "shut down" to avoid failure of an electric 

 system, or to assist in its re-establishment. If loads exceed resources, all 

 components of the electric system — generators, transmission, motors, lights, and 

 other equipment ~ try to operate at frequencies and voltages beyond their design. 

 After a period of time, they either shut down or bum out. Unlike the long-term 

 nature of conservation, curtailment is short-term and is used to avoid system failur 

 and emergencies. 



Section 1 1 of the Power Sales Contract is the contractual agreement between 

 BPA and most of its customers except Washington Water Power, Montana 

 Power Co , Portland General Electric Co., Pacific Power & Light Co , Puget 

 Sound Power & Light Co., and Tacoma City Light that provides for the 

 reimbursement of lost revenues during a period of voluntary curtailment. BPA 

 has the authority to make such reimbursement under Sections 2(f) and 5(a) of 

 the Bonneville Project Act and Section 5(b) of the Northwest Power Act A 

 copy of Section 1 1 is attached 



In anticipation of the winter-spring energy shortfalls of 1992 to 1993 related to 

 drought conditions in the summer and fall of 1992, BPA's Division of Power 

 Supply examined the utilization of Section 1 1 (b) to determine whether 

 curtailment could serve as a "resource" to meet load. 



