Regional Transmission Adequacy Guidelines

1
Regional Transmission Adequacy Guidelines

• Non-Wires Round Table
• March 2006

2
Regional Transmission Adequacy Guidelines

• Transmission Adequacy Steering Committee approved
  guidelines for N-2 outages
• Guideline is for Facilities 230 kV and below
• breaker failure
• common tower outages
• 500 kV and 345 kV main grid is covered by
  WECC/NERC

3
Regional Transmission Adequacy Guidelines

• Transmission Adequacy Steering Committee approved
  guidelines for N-2 outages
• Controlled load shedding up to 100 MW or 50 of
  total local area load is allowed
• Above 100 MW or 50 of total local area load
• Identify solutions and associated cost
• Make cost effective fixes
• Planned and Controlled load shedding up to 300 MW
  is acceptable if solutions are not cost effective
• Document findings
• Above 300 MW of total local area load
• Societal Cost/Benefit Analysis to determine
  whether to implement solution beyond planned and
  controlled load shedding
• Document findings

4
Regional Transmission Adequacy Guidelines

• Regional N-2 Guidelines
• For N-2 breaker failures and common tower outages
  
• Assumes load forecast of 1 in 2 years
• No load loss beyond the intended local load area
• No cascading
• Apply prudent utility practice
• Guidelines are voluntary

5
Regional Transmission Adequacy Guidelines
Motion to Approve Guidelines for N-2 as
stated Motion passed 8-0 with 3 abstain (and no
votes against)

• YES VOTES Eight
• Puget Sound Energy
• PGE-Power Supply
• Powerex
• Tacoma City Light

• Snohomish PUD
• PacifiCorp
• Seattle City Light
• BPA TBL

6
Regional Transmission Adequacy Guidelines Next
Steps

• Transmission Adequacy Steering Committee
• Jan. 17 Approval of TAG for N-2
• Future work continue work on remaining issues
  to be addressed
• N-2 common corridor outages
• N-1(adjusted)-1 for load area
• RAS
• Transfers Vs Load Areas
• Feb. 17 TAWG/TASC meeting
• BPA
• March Open BPA comment period
• Provide briefings to existing regional forums
  (utility, tribal, constituent, legislative, etc.)
• April BPA decision on adopting guidelines to
  standards
• April/May Begin implementation if approved