E&E News examined how PJM Interconnection handles capacity valuation, quoting AEE's Kat Burnham on capacity modeling issues used for thermal resources. Read snippets below and the full article here.

Now, clean energy advocates have their sights set on another issue they say may give coal, natural gas and nuclear generators a leg up with PJM Interconnection, a regional transmission organization that oversees the flow of power in 13 states and the District of Columbia. The issue is known as capacity value, and how PJM handles it could have implications for everything from coal plant retirements to battery deployment to the reliability of the power grid for the 65 million people living in the PJM region.PJM established a task force last year focused on potential reforms to its capacity market, including whether it should refine how it values the capacity of various energy resources. Similar discussions about capacity value are also underway in other grid regions, including California and New York, observers said.

In PJM, the capacity value for renewable resources like wind and solar projects accounts for their dependence on the weather and time of day.

But the modeling used for thermal resources in PJM — which include natural gas, coal and nuclear power plants — does not factor in the potential for a major weather event or other disruption that could knock out multiple generators at once, said Kat Burnham, principal at Advanced Energy Economy. It also hasn’t been revised significantly for about 20 years.

That raises questions about whether the system is fair for the small but growing number of renewable energy projects in PJM — not to mention the more than 200,000 megawatts of proposed carbon-free resources seeking to connect to the PJM grid, clean energy advocates say.

“When you have an outdated approach for resources like natural gas, oil and coal, they’re perhaps getting over-accredited for reliability contributions that they’re not actually providing,” Burnham said. “Whereas resources like renewables and battery storage and other advanced sources of energy … are discounted in a way that fossil fuel resources are not.”

Read the full article here.