This Planning Guide Revision Request (PGRR) adds a sixth year (Year 6) to the Steady State Working Group (SSWG) Data Set B base cases. Revisions to the Transmission Project and Information Tracking (TPIT) and Annual Load Data Request (ALDR) procedures will be required as result of this PGRR.
Reason:
The present bases cases (Data Set B) cover a planning period of five years. This timeframe is not sufficient to address large regional projects with scopes requiring long-lead time consideration (i.e., 345-kV and certification). In many cases, the entire project spectrum including initial assessments, identification of alternatives, project selection, certification, and implementation takes longer than five years.
Additionally, near-term economic projects potentially having reliability drivers beyond the five-year planning horizon can be supported with this additional base case. Similarly, this additional Year 6 base case can help provide direction to the selection of a longer term solution potentially resulting in a more cost-effective near-term plan development.
Lastly, proposed North American Electric Reliability Corporation (NERC) Reliability Standard TPL-001-2, Transmission System Planning Performance Requirements, requires assessment for one of the years in the "Long-Term Transmission Planning Horizon (years 6-10)".