The Latest from PJM on PATH
PJM Interconnection’s Transmission Expansion Advisory Committee (TEAC) released a new power point presentation yesterday with additional information on PJM’s renewed case for PATH. This new report updates a similar report that TEAC made public two weeks ago.
The new report (surprise, surprise) includes new findings that would move the “base case” need for PATH back from 2017, as predicted in the earlier report, to 2015.
Although you might not understand a lot of what is in the TEAC report, look for references to “demand growth” and “CETO.” The TEAC does not include any information about what values or assumptions are used for predicting growth in demand in eastern PJM or what hypothetical predicted values PJM is using for CETO, the required transfers of electricity into eastern PJM to meet that demand.
All of the N-1-1 “violations” (of NERC standards) noted in the report are all derived from the values assigned to demand growth and CETO volumes in PJM’s predictions. Unless we know what values PJM is using for demand predictions and west to east power transfers, there is no way to evaluate the validity of TEAC’s claims about NERC violations. There are lots of pretty maps and spreadsheets in the TEAC power point, but if their underlying assumptions are wrong, then all these pretty pictures are meaningless.
PJM’s load flows are all based upon “emergency transfers” (the “ET” of CETO), that is power flows at peak load. This is not the same as total or aggregate demand. When PJM speaks of “demand growth” in its predictions, it is talking only about peak demand which creates the “emergency transfers” in its contingency “model.”
What do we know about peak demand in PJM? Well, we know that the expansion of demand side resources in PJM has been explosive in the last few years. The main impact of demand side management is the reduction of peak demand. So it would be very interesting to see how PJM incorporates its own peak demand reduction efforts into its predictions of “demand growth.” One further note: “demand growth” has been negative for the last four years, it will be interesting to see PJM’s reasoning about how and why that will change in the next 20 years.
For a good assessment of the assumptions PJM’s TEAC used in last year’s argument for PATH, see testimony by independent grid experts George Loehr and Hyde Merrill in East Virginia last fall. Here is an example of Loehr’s comments on PJM’s projected power transfer values:
• In my view, the Load Deliverability procedure used by PJM comes up with Capacity Emergency Transfer Objective (CETO) values that are unnecessarily high, and seems out of synch with what the rest of the industry is doing. There are better, more systematic and technically consistent ways to determine the import capabilities required by Load Deliverability Areas (LDAs) to maintain reliability.
• Without PATH, the capability of the Mid-Atlantic LDA to import power would still be in excess of 6,000 MW. In other words, with a 6,000 MW transfer into the Mid-Atlantic area, there would be no reliability violations. Not one.
• In my opinion, NERC violations have not been established since the base case assumptions are too conservative. So, too, are the CETO/Load Deliverability procedures.
We have yet to see a public discussion of the values PJM is using in its 2010 TEAC reports.