By Glenn Davis
For more than two decades, the regional grid operated by PJM has relied on a capacity market to ensure enough power plants exist to keep the lights on. The concept behind PJM’s Reliability Pricing Model was straightforward: When energy markets alone could not sustain the generation needed for reliability, the capacity market would fill the gap.
It was never meant to carry the entire system.
Originally, the capacity market was designed to procure the final slice of reliability, the last increment needed to ensure adequate reserves. Most generation was expected to be supported by energy market revenues, bilateral contracts or traditional utility planning.
But over time, the system changed.
Energy prices remained relatively low. Merchant generation expanded. State policies began influencing wholesale market outcomes. At the same time, dispatchable generation began retiring faster than it was being replaced.
Now demand is accelerating again, driven by electrification and the explosive growth of artificial intelligence and hyperscale data centers. (See PJM Pushing Forward on Efforts to Meet Rising Data Center Load.)
The result is that PJM’s capacity market has quietly evolved from a reliability safety net into the primary mechanism supporting much of the region’s electricity supply. What once was designed to secure a modest share of reliability is increasingly responsible for financing nearly all of it.
That shift has exposed a fundamental problem: The market structure was never designed for this role.
Poorly Suited Structure
Today, PJM’s capacity market relies on a three-year forward auction that provides generators with only a one-year commitment. That structure may have worked in a slower-growing system with lower capital requirements, but it is poorly suited for the infrastructure challenges now facing the grid.
The consequences are becoming clear.
When long-term infrastructure needs are forced into short-term market structures, volatility follows. Even modest changes in supply or demand — plant retirements, transmission constraints or revised load forecasts — can trigger dramatic price swings as the market attempts to correct years of underinvestment in a single auction. The result is uncertainty for consumers and developers alike.
And uncertainty is the enemy of investment.
Power plants, whether natural gas, nuclear, storage or emerging technologies like small modular reactors, require significant upfront capital and long development timelines. They cannot be financed on the basis of a single year of capacity revenue.
If the region expects markets to deliver new generation, those markets must provide the revenue certainty required to build it.
Complementary Tiers
One potential path forward is to restructure the capacity market into two complementary tiers.
The first tier would procure the majority of the region’s reliability needs, roughly 70 to 80%, through longer-term commitments of approximately seven years. Auctions still could occur three years in advance, but the extended contract duration would provide the predictable revenue stream necessary to finance new generation.
This approach does not require higher prices. In fact, the opposite may be true.
Longer-term commitments reduce financing risk and lower the cost of capital, making new generation easier to finance. Existing generation would benefit from reduced revenue volatility and a longer recovery horizon for fixed costs. As a result, new and existing generation could clear the market at lower prices than under the current one-year structure, potentially at or below today’s market cap.
In other words, reliability does not necessarily require higher prices — it requires greater certainty.
The second tier would remain a shorter-term capacity market, covering the remaining 20 to 30% of system needs. This segment would preserve flexibility, allowing PJM to adjust for forecast errors, plant retirements and unexpected changes in demand.
Together, these two tiers would align long-term investment signals with short-term system needs, strengthening both reliability and market efficiency.
Capacity Contracts
There is also an opportunity to better align the market with the fastest-growing source of demand.
Hyperscale data centers, now a primary driver of load growth, often are willing to enter into long-term agreements to secure reliable power. Allowing these large customers to participate in optional long-term capacity contracts, potentially 15 years in duration, could help finance new generation while shifting a portion of reliability risk away from ratepayers.
Major technology companies already are signing long-term energy agreements across the country. Integrating similar mechanisms into the capacity market could accelerate the development of the generation needed to support continued economic growth.
None of these ideas abandon competitive markets. They recognize that electricity markets must evolve as the system around them changes.
When PJM’s capacity market was created, the grid faced slow demand growth and ample reserves. Today, it faces rapid load growth, significant retirements of dispatchable generation and increasing pressure to build new resources quickly and at scale.
The market already has changed in practice. It is time for the design to catch up.
If the capacity market originally was designed to procure the final slice of reliability, the grid now depends on it far more than its architects ever envisioned. The challenge no longer is whether it should play a central role, but how to structure it to succeed.
The future of the grid, and the economic growth it supports, depends on getting that answer right.
Glenn Davis is the president of Davis Energy & Infrastructure Strategy Group and served as director of the Virginia Department of Energy and a member of the Virginia House of Delegates.
