Regional Transmission Expansion Planning


RTEP Drivers

PJM uses an open process to plan for changes to the electric grid in the 13-state region to maintain future reliability and economic performance of the grid. The PJM Regional Transmission Expansion Planning process, performed annually, looks ahead 15 years, assessing many drivers that affect grid reliability. PJM studies many scenarios and analyzes various grid conditions that could lead to problems in the way power flows throughout the region. These problems might include:

  • Transmission lines that are carrying the maximum amount of electricity that they are able to carry
  • New generators, which, when they begin operating, could cause parts of the system to be overloaded due to the increased amount of power flowing on the lines
  • Substation equipment that could be overloaded

PJM also considers public policy needs such as the impact of state renewable energy requirements or demand response/energy efficiency efforts, generator retirements and fuel shifts such as the major change from coal to natural gas generation.

When PJM identifies potential problems, we work with transmission owners and other members to determine the best fix for the problem, meeting required national standards. Examples of these fixes include:

  • New transmission lines
  • Replacing existing high-voltage transmission lines with lines capable of carrying more power
  • Installation of devices that maintain voltage levels

The Regional Transmission Expansion Planning process determines the need for and benefits of a transmission project; it does not review or approve locations where transmission lines are ultimately built. That is the responsibility of individual states.

All transmission improvements identified through this process are discussed publicly in stakeholder meetings, and reviewed and approved by the PJM Board before being included in PJM’s expansion plan. The cost of these upgrades is allocated to PJM transmission owners following rules in PJM’s federally-approved governing documents. Under PJM agreements, transmission owners are obligated to build transmission projects approved by the PJM Board that are needed to maintain reliability standards.