Grid Resilience, Methodology Analysis at Center of Planning Committee Meeting 


PJM stakeholders looked at how system planning will evolve in the future at the Planning Committee meeting Thursday.

Mark Sims, manager – Transmission Planning, presented a preview of a refresh of the light load reliability analysis methodology as well as an introduction to grid resilience in system planning.  In response to stakeholder feedback, PJM also continued discussions on capacity emergency transfer limit calculation methodology.

Sims gave a broad overview of how grid resilience might factor into planning discussions, and what might motivate and drive resilience analysis.

System planning’s focus on resilience will look to developing metrics and simulations for any number of situations, such as the incidents in the North American Electric Reliability Corporation’s extreme event analysis (but not limited to the NERC list).  PJM discussed the extreme events as examples of disturbances that might be a good place to start evaluation simulations of grid resilience.

Through an integrated effort across operations, planning, markets and security, PJM will work with members, industry, government entities and other grid operators to develop technologies, strategies, tools and systems that reflect the broader PJM “resilience roadmap.”

PJM said the conversation will cover routine and challenging events – examining the impact of an event, how to develop metrics and quantify steps within the system planning process.

PJM is examining  its methodology for light load analysis; PJM may modify testing to reflect current operations and refresh some of the test parameters to reflect recent historical data.

The “light load period” is defined as 1 a.m. until 5 a.m. each day, from Nov. 1 through April 30. PJM is reviewing historical data to determine how well the current study parameters correlate to the existing data.  The current light load reliability analysis standards were originally established in 2011.

Several PJM zones experience light load conditions of less than 35 percent of peak load during a significant number of hours. One potential recommendation is to decrease the load modeling assumption, as a percentage of forecasted summer peak, from the current 50 percent to a new, lower percentage of the summer peak forecast.

Stakeholders and PJM continue to work on potential proposed changes to capacity emergency transfer limit calculation methodology. Currently, PJM models firm external transfers and assumes non-firm external support is up to the capability of the transmission system in the PJM footprint.

PJM is looking to revisit its approach to external transfers. One possible solution is to only model firm transfers to and from non-PJM zones and not rely on non-firm assistance from non-PJM zones.

Stakeholders endorsed the new Manual 14F: Competitive Planning Process, including the decisional diagram. PJM and stakeholders have been working over several months to develop the new manual, including collecting information from several different sources and on refining language. PJM pointed out that there are additional special PC meetings on topics such as cost caps/containment. Final approval will be at the June Markets and Reliability Committee meeting.


  • The overhead transmission lines section of the minimum design requirements document from the Designated Entity Design Standards Task Force. Other sections will be presented for endorsement at a later time. Once an entity signs the designated entity agreement with PJM, it must follow all of the proposal requirements.
  • Updates to Manual 14C: Generation and Transmission Interconnection Facility Construction, aligning manual language with the work of the Designated Entity Design Standards Taskforce
  • Installed reserve margin study assumptions as developed in the Resource Adequacy Analysis Subcommittee
  • Updates to Manual 20: PJM Resource Adequacy Analysis – language on zonal and global locational deliverability areas for capacity emergency transfer objective calculations

First Readings  

Informational Updates