PJM's Capacity Gap Widens as Data Center Load Outpaces Supply
The grid operator's latest auction fell 6,831 megawatts short. New large-load rules move electrical capacity onto the underwriting sheet.
By Keith Reynolds | Publisher & Editor, ChargedUp!
138,318 megawatts. That is how much generation and demand response PJM Interconnection secured in its 2028/2029 Base Residual Auction, the largest capacity market in the country. The auction cleared at a Federal Energy Regulatory Commission (FERC) approved cap of $325 per megawatt-day and still landed 6,831 megawatts short of PJM's reliability requirement.
For anyone underwriting a project inside PJM's 13-state footprint, that gap is no longer an abstraction. PJM is widening its response to data center load growth through a new large-load registry, revised curtailment rules, and a one-time capacity procurement designed to close the shortfall before it becomes an outage.
The Auction Falls Short Again
PJM's own planning materials explain why. The grid operator's 2025 Long-Term Load Forecast projected 32 gigawatts of peak load growth between 2024 and 2030, with all but 2 gigawatts of that growth coming from data centers. Over a 20-year horizon, PJM expects summer peak demand to climb roughly 70,000 megawatts, to about 220,000 megawatts.
Data centers concentrate that demand into large blocks that arrive on a construction schedule, not a generation schedule. A market clearing at its price cap while still falling short of the reliability requirement signals that price alone has not yet drawn enough accredited capacity into the system for the delivery year the auction covers.
That does not mean every site in PJM territory carries the same risk. It does mean electric service now belongs on the same underwriting line as zoning, access, and entitlement risk, evaluated and documented before capital moves.
Large Loads Get a New Gate
PJM is responding with a more formal admissions process for big electricity users. In August 2026, the grid operator proposed a framework to connect data centers without compromising reliability or affordability, anchored by a Large Load Registry that tracks existing and new large loads by location, scale, and timing.
The same proposal links large-load service to curtailment exposure. Under PJM's plan, curtailment of certain large loads would happen before PJM calls on Load Management customers, who are paid in advance to reduce electricity use. A site that can be curtailed under defined circumstances carries a different risk profile than a site with firm service and a documented resource adequacy path, and that distinction now belongs in lease negotiations and tenant improvement schedules, not just interconnection agreements.
PJM's board has added a capacity backstop to the same effort. The grid operator planned a one-time Reliability Backstop Procurement running from September 30 through October 21, 2026, with results expected in early December, aimed at closing short-term reliability gaps tied to large-load growth.
Power Risk Moves Into the Pro Forma
The financial exposure starts well before an outage or a curtailment event. It starts the moment a project cannot confidently answer when power arrives, how much load the site can carry, who pays for upgrades, and whether future expansion is possible. Those answers flow directly into rent commencement dates, tenant improvement timing, construction carrying costs, and refinancing assumptions.
Electrical capacity is now a direct input into net operating income. A building that cannot support tenants with higher power intensity loses leasing flexibility. A project that needs a service upgrade has to pull capital from other improvements. A landlord with uncertain power timing negotiates from a weaker position, particularly when the tenant's operations depend on computing, refrigeration, or process loads that do not tolerate interruption.
The capacity price signal belongs in that same conversation. PJM's 2028/2029 auction cleared at $325 per megawatt-day and still procured less capacity than required. That figure does not translate automatically into a specific line-item increase for any one building, since retail tariffs, supplier contracts, demand charges, and load profiles vary by market and by lease. It does justify a closer look at electricity cost recovery, demand management, and lease language in any market where large-load growth is reshaping the resource adequacy balance, and every $1,000 in annual energy cost avoided still supports roughly $12,500 in added asset value at an 8% cap rate.
The Execution Test Shifts Earlier
The clearest lesson from PJM's 2026 actions is that electrical diligence now belongs at the start of site selection, not the end of design. The same load data that supports a utility service request should also shape the land bid, the building layout, the lease strategy, and the capital budget.
Onsite generation, storage, and load-management tools have a role here, but they work best as execution tools tied to a documented service constraint and tariff structure, not as blanket substitutes for grid service. A battery or backup generator sized around an assumed load profile can leave a site exposed if the underlying utility timeline shifts.
A credible growth plan in PJM territory now needs evidence of utility coordination, a realistic energization schedule, a load ramp that matches confirmed service, and a capital plan for any required upgrades. Development models should distinguish between confirmed service, requested service, service pending a utility upgrade, and service that depends on a regional capacity mechanism such as the Reliability Backstop Procurement, since each category carries a different schedule, contingency reserve, and asset-value implication.
Projects that answer those questions early move faster through financing and leasing. Projects that assume power arrives on demand are now carrying a risk the grid itself has made visible.
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