PJM Reliability Backstop Auction: Who Pays for Data Center Shortfalls

What the backstop auction is trying to fix

PJM's 2028/29 Base Residual Auction procured 138,318 MW at the FERC-approved price cap of $325 per MW-day, but that cleared supply plus Fixed Resource Requirement resources still fell 6,831 MW short of the one-event-in-ten-years reliability requirement [pjm-2028-29-auction]. PJM said it plans to seek FERC approval for a special Reliability Backstop Procurement in September 2026 to address the near-term supply gap [pjm-2028-29-auction].

A shortfall on paper does not mean blackouts are imminent. PJM reported a 14.7% reserve margin for the 2028/29 delivery year [pjm-2028-29-auction]. It does mean the market is operating with slimmer headroom than planners want, and that extra procurement has a cost someone must pay.

Why data centers entered the cost-allocation fight

Load growth is the driver. PJM's forecasted peak for 2028/29 is about 2,000 MW higher than the prior auction's forecast, with large data center loads a major contributor to the revised numbers [pjm-2028-29-auction]. Governors in PJM states have pressed for protections for residential and existing commercial customers as capacity prices hit caps three years running.

Pennsylvania Governor Josh Shapiro issued an executive order directing the PUC to assign backstop auction costs to data centers where possible [pa-shapiro-pjm-eo]. PJM's board letter to governors described Connect and Manage frameworks that let large new loads connect but curtail during emergencies, plus bilateral long-term contracts between large loads and generators [pjm-board-backstop-letter]. Utility Dive reported the board approved a backstop auction framework alongside data center curtailment concepts [utility-dive-pjm-backstop].

For a cannabis cultivator, this matters indirectly. You are not a 500 MW hyperscale load, but you share the same RTO footprint and the same supply-side capacity charges. If backstop costs land on general load because state policy cannot isolate data centers, your supplier pass-through rises. If states succeed in assigning costs to flexible large loads, cultivators still face tighter reserves and higher baseline capacity prices.

What lands on a cultivator's bill

Capacity in PJM is a wholesale cost that retail suppliers embed in fixed or pass-through supply rates. It is not a utility delivery charge you can optimize with demand charges alone. When the RPM clearing price hits the cap, every megawatt of uncovered load exposure costs more for the June through May delivery year.

Assume your facility sits in ComEd territory with 800 kW of peak demand and your supplier passes through PJM capacity at the RTO clearing price without a hedge. At $325/MW-day, one MW-year of capacity obligation costs about $118,625 before margin [pjm-2028-29-auction]. Your 0.8 MW share is roughly $94,900 annually if fully exposed, or about 9.9 cents per kWh if you consume 960,000 kWh in a year. That is an illustrative stack, not a bill quote; your supplier's contract language controls how much capacity you buy and whether the price is fixed.

Backstop procurement adds uncertainty on top of the capped auction. Until FERC approves the mechanism and states finalize allocation rules, suppliers may widen capacity pass-through clauses in new quotes.

How this differs from transmission and delivery

PJM wholesale costs split into energy, capacity, and transmission components. Your utility's delivery bill covers wires, transformers, and often a distribution demand charge. Capacity is typically a supply-side line item unless your utility default rate bundles it.

Cannabis facilities with flat, high load factors pay capacity on nearly every megawatt of peak contribution. A data center with parallel redundant feeds may have different peak contribution rules, which is why governors argue they should bear incremental backstop costs [pa-shapiro-pjm-eo]. Until orders are final, assume your supplier will quote capacity exposure conservatively.

Timeline for operators

Milestone	Expected timing	What to watch
Backstop filing to FERC	Fall 2026	Whether costs are socialized or class-specific
2028/29 capacity billing	June 1, 2028	RPM cap price already set at $325/MW-day
State PUC orders	2026-2027	PA, NJ, MD, IL dockets on large-load cost assignment
Connect and Manage enrollments	Rolling	Whether flexible curtailment credits appear for C&I

Practical steps before your next contract

Read your supply contract's capacity language now. Look for "RPM," "UCAP," "pass-through," and "change in law." A fixed all-in rate may still exclude capacity if the band is narrow.

Do not assume staggered lights fix capacity. Peak kW management helps delivery demand charges. Capacity obligations are based on your supplier's portfolio assignment and peak load contribution rules, not your best 15-minute interval.

Time renewals against delivery years. PJM capacity applies June 1 through May 31. A contract starting in March may cross two capacity periods with different clearing prices.

Track state PUC dockets. Pennsylvania, New Jersey, Maryland, and Illinois PUC proceedings on cost allocation will determine whether backstop charges appear as a separate rider or inside supplier quotes [utility-dive-pjm-backstop].

What Connect and Manage means when hyperscale loads curtail but flower rooms cannot

PJM's board letter described Connect and Manage as a way to connect large new loads while allowing curtailment during emergencies [pjm-board-backstop-letter]. Data centers with redundant feeds may accept dispatchable curtailment contracts that lower their share of future backstop costs. Cannabis cultivators generally cannot darken flower rooms on ISO notice without crop loss, which keeps you in the existing commercial class that pays baseline RPM at the capped clearing price [pjm-2028-29-auction].

The policy fight is whether backstop procurement costs get assigned only to loads that opt into flexible connection agreements or spread across all LSE obligations. Shapiro's Pennsylvania order pushes assignment toward data centers [pa-shapiro-pjm-eo]. If that succeeds, baseline RPM may stay high but a separate backstop rider might skip small C&I. If assignment fails, suppliers socialize backstop MW across the entire RTO [utility-dive-pjm-backstop].

Illustrative exposure on top of capped RPM:

Assume backstop clears at $400/MW-day for 500 MW procured (hypothetical clearing; final prices are unknown until FERC approves the auction [pjm-2028-29-auction]). Total backstop cost about $73 million annually ($400 × 500 MW × 365). Spread over 138,318 MW procured in the 2028/29 BRA [pjm-2028-29-auction], that adds roughly $530 per MW-year or about 0.05 ¢/kWh at a 50% load factor. Small per kWh, but suppliers may markup or concentrate charges in pass-through clauses.

Your actionable item is contract language, not lobbying. Read whether your supplier can pass through "reliability must-run," "backstop procurement," or "change in law" adders added after signature. Fixed rates with narrow capacity bands offer less protection than they appear when the 6,831 MW shortfall triggers supplemental procurement [pjm-2028-29-auction].

What suppliers are likely to do in quotes

Retail suppliers facing a third capped auction and a possible backstop layer often shift risk to customers through index capacity, shorter fixed terms, or explicit RPM adders. If you are shopping in Pennsylvania, Ohio, or New Jersey, ask for a line-item breakout of capacity at the RTO clearing price versus any markup.

A cultivator comparing two quotes should match delivery year, capacity inclusion, and swing bandwidth. A lower energy rate with uncapped capacity pass-through can cost more than a higher fixed rate once RPM and backstop charges flow through.

How Illinois and Pennsylvania cultivators should read state allocation fights

Governors are not debating whether cultivators pay RPM. That charge is already embedded in supply rates across PJM [pjm-2028-29-auction]. The open question is whether backstop procurement costs sit on top of capped RPM for everyone or get assigned to large flexible loads that opt into Connect and Manage [pjm-board-backstop-letter] [pa-shapiro-pjm-eo].

Pennsylvania's executive order directs the PUC to push backstop costs toward data centers where possible [pa-shapiro-pjm-eo]. Illinois cultivators on ComEd still shop supply in a state watching the same PJM shortfall, but Illinois has not mirrored Pennsylvania's order language. New Jersey and Maryland PUC dockets may land differently again [utility-dive-pjm-backstop]. Multi-state MSOs cannot assume one state's allocation outcome applies to another meter.

Illustrative split for a 600 kW Philadelphia grow versus a 600 kW Chicago grow, both on pass-through capacity:

Line item	Philadelphia (PECO)	Chicago (ComEd)
2028/29 RPM at cap	$120,147/MW-year × 0.6 MW ≈ $72,088 [pjm-2028-29-auction]	Same RTO cap [pjm-2028-29-auction]
Hypothetical backstop adder (socialized)	Shared across all LSE load if PA assignment fails [utility-dive-pjm-backstop]	Same RTO socialization risk [pjm-2028-29-auction]
Delivery demand	PECO tariff kW charges (separate from RPM)	ComEd tariff kW charges (separate from RPM)

The table shows supply-side symmetry and policy-side uncertainty. Your procurement task before fall 2026 is to capture supplier assumptions in writing: if FERC approves backstop procurement, does your contract pass it through at cost, cap it, or exclude it entirely [pjm-board-backstop-letter]?

Ohio cultivators in FirstEnergy or AEP Ohio territory face the same RPM cap but different default supply bundles. Pull the capacity line on your June 2028 invoice prototype from a supplier who models PJM pass-through explicitly. If the quote only shows a blended ¢/kWh, ask for RPM, losses, and ancillaries broken out before you compare to a neighbor in another PJM state.