Regional Transmission Expansion Planning


PJM plans ahead to keep the lights on and electricity affordable for more than 67 million people in our 13-state region and Washington, D.C.

Our Regional Transmission Expansion Planning (RTEP) process looks years into the future to decide what upgrades or new facilities the electric grid will need. This helps prevent problems, support state energy goals and make sure electricity can move where it’s needed – even during extreme weather.

PJM’s planning has two layers:

  • Annual Planning: Every year, we look up to 15 years ahead to spot reliability and efficiency needs.
  • Long-Term Planning: We also run big-picture studies at least every five years to look 20 years or more ahead, using scenarios that account for changes in technology, the economy and electricity use.

We also work with neighboring grid operators to plan projects that benefit multiple regions.

What We Look For

When we study the grid, we look for signs that something in the future might cause trouble. For example:

  • Overloaded lines: Transmission lines carrying as much electricity as they safely can
  • New generators: When new power plants connect to the grid, they can change how electricity flows and overload certain lines.
  • Substation limits: Transformers and other equipment nearing their safe capacity
  • Fast-growing demand: Large clusters of new facilities – like data centers and manufacturing plants – needing big amounts of power
  • Resilience needs: Preparing for severe weather, fuel supply issues and other risks

We also factor in state energy policies, such as renewable energy targets, and trends like older power plants retiring or switching from coal to cleaner fuels.

Since 2023, RTEP studies have been linked with PJM’s cluster-based interconnection process – a way of studying groups of new projects together so that neededupgrades are identified earlier.

Finding Solutions

When potential issues are identified, PJM’s role is to plan and coordinate the solution. PJM does not own or operate transmission lines or substations. Instead, PJM works with the region’s transmission-owning utilities and other stakeholders to determine the best approach. Possible solutions include:

  • Building new transmission lines
  • Rebuilding existing lines so they can carry more power
  • Adding equipment that keeps voltage steady
  • Using advanced grid technologies to improve efficiency

Since 2022, we’ve used numbered solicitation “windows” (such as 2024 Window 1) to request ideas from qualified companies. If a risk is urgent, we may use a faster “Immediate-Need” process.

We evaluate proposals using six criteria:

  • How well does it solve the problem?
  • Cost
  • Ability to expand if needed
  • Impact on communities and the environment
  • Risks to success
  • Efficiency – whether it can address more than one need at once

How Decisions Are Made

We share our findings at public Transmission Expansion Advisory Committee (TEAC) meetings, where anyone can listen and comment.

After reviewing all input, PJM recommends projects to our Board of Managers.

  • The RTEP specifies what projects are needed but not exactly where they are built – that’s up to project developers and are approved by state governments.
  • States that want to advance policy-driven projects can work with PJM through the State Agreement Approach (SAA) (PDF).

Paying for the Upgrades

The cost of approved projects is shared among PJM’s transmission owners according to federal-approved rules. Transmission owners are required to build projects once they’re approved, and PJM files the cost-sharing plan with the Federal Energy Regulatory Commission (FERC).