Power grid expansion for the PJM Interconnection

The PJM Interconnection is the electric power grid operator for several eastern and midwestern states. The service area includes New Jersey, Pennsylvania, Maryland, Delaware, Virginia, West Virginia, Ohio, plus parts of other states, including the Chicago area of Illinois. I believe it is the largest grid operator in the US, in terms of population served.

PJM recently announced the selection of over 11 gigawatts of additional capacity for its system. Most of this new capacity will be combined cycle natural gas power plants, along with new battery storage and even some new nuclear power. Some of the new capacity will be upgrades (uprates) to existing power plants, while much of it will be new power plants.

Summary breakdown of PJM’s new capacity additions, in megawatts (MW)

Natural gas combined cycle    7,756 MW
Battery storage               2,275
Nuclear                       1,383
Natural gas turbines            365
Coal uprate                      14
---------                   -------
Total                        11,793

Since this is all part of PJM’s Reliability Resource Initiative, the new capacity was chosen to enhance reliability on the grid. Therefore, there isn’t any new solar or wind renewable capacity. There is a note that 20 MW of existing wind power will be added to “Capacity Interconnection Rights”.

For the additional nuclear power, they identified 496 MW to be added by uprating existing plants, and 887 MW of new capacity. The following link says all of the new capacity is expected to be on-line by 2031. It seems unlikely new nuclear will be available by that year, but they appear to be optimistic in the timeline. Also, 887 MW for new nuclear seems like a strange number. It would be too small for one AP1000, for instance. Perhaps they are planning for three of the BWRX-300 plants from GE, or some similarly sized SMRs from Westinghouse or other suppliers. I will be interested to learn how that 887 MW comes about.

_ Pete

3 Likes

The 887 MW of new capacity nuclear is the Constellation project to rebuild and restart the old Three Mile Island Unit 1 reactor.

1 Like

PJM needs to complete these capacity additions to the grid because PJM has major grid reliability concerns:

PJM has been warning that it faces looming power supply shortfalls as its supply isn’t keeping up with demand. That dynamic was reflected in the jump in clearing prices from PJM’s last capacity auction, which sparked backlash over rising electric bills and moves by the grid to boost supplies.

According to a February 2024 study by Quanta Technology, the PJM Interconnection power grid, a regional transmission organization that coordinates the movement of wholesale electricity in all or parts of 13 states and the District of Columbia, faces possible issues with two key indicators of grid reliability unless steps are taken immediately.

1 Like