Solar power makes up about 58% of resources looking to connect to PJM system

Solar power generation has overtaken natural gas in PJM Interconnection's resource connection queue, tripling over the past two years to total nearly 94,000 MW, or around 58% of resources in the queue, with gas-fired plants constituting 14.8% of queued generation.

In 2021, the PJM Board approved $920 million in 118 baseline transmission projects, according to the grid operator's 2021 Regional Transmission Expansion Plan that was published March 8.

The annual RTEP report conveys planning study results throughout the year and explains the rationale behind transmission system enhancement needs.

The report also examines trends that continued throughout 2021 and will "drive PJM's grid of the future, including the ongoing shift from fossil fuels to renewables and the impact of public policy," the grid operator said in the report.

The 118 baseline transmission projects fell within three main categories:

• 23%, or $213 million, of projects were prompted by 52 generator deactivations or retirements
• 25%, or $229 million, of projects were driven by PJM and North American Electric Reliability Corporation criteria
• 52%, or $478 million, of projects were driven by transmission owner criteria

The board also approved 34 new network transmission projects at an estimated $48 million. Network projects allow new generators to reliably connect to PJM's system.

The RTEP process has been managing "an unprecedented capacity shift" driven by federal and state policies and broader power generation fuel economics, the report said.

This shift is characterized by new generating plants powered by Marcellus and Utica shale natural gas, new wind and solar generating units driven by federal and state renewable incentives, generating plant deactivations, and market impacts caused by demand response and energy efficiency programs, according to the report.

Fuel-mix changes

In addition to solar resources accounting for 58% of about 160 GW of resources in PJM's interconnection queue, gas-fired plants total nearly 24 GW, or 14.8% of queued generation, while utility-scale energy storage facilities and wind-powered generation account for another 21.1% and 5.4%, respectively, the grid operator said.

More than 31 GW of coal-fired generation has been retired since 2011, with environmental public policy and plant age — many over 40 years old — making them "prohibitively expensive" to operate, PJM said.

Totaling over 137 GW of Capacity Interconnection Rights, renewable fuels are "changing the landscape of PJM's interconnection queue," according to the report, with state policies encouraging renewable energy generation leading to the increase in solar generation interconnection requests.

Queued requests as of Dec. 31 for CIRs totaled 8,800 MW of wind-powered generators that were actively under study, suspended, or under construction, with those CIRs corresponding to nameplate capacity totaling 39,589 MW, the report said.

Nameplate capacity represents a generator's rated full power output capability, but power plants do not operate at full nameplate capacity 100% of the time.

Queued solar-powered generator requests for CIRs totaled 93,756 MW actively under study, suspended, or under construction, with those CIRs corresponding to nameplate capacity totaling 150,953 MW, the RTEP report said.

Offshore wind development is also set to alter PJM's transmission needs over the long term. Maryland, New Jersey, and Virginia have all enacted offshore wind targets that total 14,723 MW with planned in-service dates by 2035 and North Carolina recently announced an 8 GW target by 2040, PJM said.

PJM conducted the first phase of an offshore wind transmission scenario study in 2021 that considered the integration of between 30 GW and 80 GW of renewable generation with the study identifying the need for as much as $3 billion in transmission upgrades to meet state-level Renewable Portfolio Standard goals in the next 10-15 years.

"The injection of thousands of megawatts from offshore wind will fundamentally change how power flows over the transmission grid in the Northeast and mid-Atlantic," PJM said.

The generation will be located closer to load centers along the I-95 corridor, an area of the grid originally served mainly by west-to-east power flow from large mine-mouth coal-fired power plants in western Pennsylvania and beyond. Later, shale gas-fired plants in central Pennsylvania served the area, according to the report.

New transmission assets and configurations will be needed to address these changes, PJM said.