fyi
---------------------- Forwarded by Tim Belden/HOU/ECT on 04/03/2001 07:03 AM ---------------------------


Steve Walton
04/03/2001 07:47 AM
To:	Tim Belden/HOU/ECT@ECT
cc:	Alan Comnes/PDX/ECT@ECT, Susan J Mara/NA/Enron@ENRON, James D Steffes/NA/Enron@Enron, Richard Ingersoll/HOU/ECT@ECT, Joe Hartsoe/Corp/Enron@ENRON 
Subject:	WSCC Reserve Standard

Tim,

After receiving Dick's message regarding the changes in the WSCC Reserve Standard, I went through the documents to try to understand the change being proposed.  I also made talked with some of the people who have been participants in the development of the new standard, to check on my understanding and ask a few follow-up questions.

While on its face, the reserve requirements are being lowered the standard is actually being tightened, because the new standard deals with the locations at which reserves are covered.  In the past, a party could carry all of its spin on a single unit.  The new standard is based on governor responses to frequency excursion.  It requires that the reserve be spread across more units or that special control features be added to AGC to allow carrying more reserves on some machines.  

As Dick indicated in his note, there is some potential for a reduction in system transfer capability.  For instance, carrying more reserves on NW hydro units in some hydrological conditions has the potential to reduce the Pacific Intertie rating by up to 20%.  However, given the limited reserves available in California, we are probably already in this condition.  With California at 1.5% reserve, there is a concern that the rating is already impacted.  On the other hand, when more generation comes on-line in California with new construction, then the reserve levels rise and the impact on transfer capability is mitigated.  

The other effect of this change is that it reduces the amount of Frequency Response Reserve (FRR) that California has to buy.  Whether the change in the responsibility to buy actually changes to pattern of reserves on machines cannot be determined at present.  However the change does have financial benefits to those who are chronically short of FRR.

Finally, I wondered how the shift to from individual control areas to a single control area with the formation of RTO West would affect the reserve requirements, since the new standard talks about carrying reserves by control area or reserve sharing pool.  I was reminded that the Northwest is a reserve sharing pool.  Since , the Northwest Power Pool and RTO West represent essentially the same portion of the system.  the RTO formation will not result in a major change in requirements.  

If you have additional questions, I will dig deeper.

Steve