Exploring PJM: The Basics of RTEP

Exploring-PJM-IconOne of PJM’s three priorities – along with keeping the lights on and buying and selling electricity through its market operations – is managing the growth of the electric system.

To do that, PJM conducts a long-range Regional Transmission Expansion Planning process. It looks at a 15-year planning horizon and identifies transmission system additions and improvements needed to keep electricity flowing in the PJM region.

A collaborative process, the RTEP considers a number of drivers – load growth, interconnection analysis, generator deactivation and operational performance – as it plans for future needs of the electric grid in accordance with established reliability criteria.RTEP Process - RTO Perspective

PJM studies many scenarios and analyzes various grid conditions that could lead to problems in the way power flows throughout the region, such as:

  • Transmission lines 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. Planning also studies the impact of potential generator retirements and fuel changes such as the current shift from coal to natural gas generation.

When PJM identifies potential problems, it works with transmission owners and other members to determine the best solution that complies with regulations and industry standards. Examples of these fixes include:

  • Authorizing the building of new transmission lines
  • Replacing existing high-voltage transmission lines with lines capable of carrying more power
  • Installing devices that maintain voltage levels.

Factors Driving System ExpansionImprovements identified through this process are discussed in stakeholder meetings. The M-14 series of PJM manuals contain the specific business rules that govern the RTEP process.

All transmission upgrades fall into three categories: baseline, network and supplemental. Baseline upgrades resolve a system reliability criteria violation. Network upgrades are new or upgraded facilities that would eliminate reliability criteria violations caused by proposed generation, merchant transmission or long-term firm transmission service requests. Supplemental projects are projects initiated by the transmission owner to satisfy local transmission needs.

The PJM Board of Managers needs to approve all baseline and network projects before formally become part of PJM’s RTEP.