The disclosure and our analysis
Evidence dates
Evidence: FERC order in Docket ER26-3257, issued September 22, 2026, and the docket's filing record from July 24 to September 17, 2026; Utility Dive reports dated August 24 and September 23, 2026.
The Federal Energy Regulatory Commission issued an order on September 22, 2026 rejecting Commonwealth Edison's notice of cancellation of its transmission security agreement with PowerHouse Hillwood Holding, according to FERC's docket record in ER26-3257. Utility Dive reports the agreement supports a 1.8 GW, $20 billion data center PowerHouse Hillwood is developing in Joliet, Illinois. The underlying credit support dispute is pending in the U.S. District Court for the Northern District of Illinois. [Source 1] [Source 4]
What FERC decided
FERC's docket index describes the September 22 issuance as an "Order Rejecting Notice of Cancellation re Commonwealth Edison Company under ER26-3257." Chairman Swett and Commissioner See filed a joint concurrence, and Commissioners Rosner and LaCerte filed a separate concurrence. [Source 1]
Utility Dive reports that FERC declined to assert primary jurisdiction over the contract interpretation question and left it with the federal court in Illinois, where the dispute is already pending. The Swett and See statement, as quoted by Utility Dive, says the commissioners "decline to assert primary jurisdiction over the interpretation of ambiguous contract terms involving credit support." [Source 4]
We could not open the order text itself through FERC's public file service. The procedural facts above come from FERC's docket index. The reasoning and quotes are attributed to Utility Dive's report of the order.
How the dispute got here
ComEd filed a tariff filing on July 24, 2026 titled "Cancellation of Hillwood," proposed to take effect July 25, 2026. [Source 2] PowerHouse Hillwood moved to intervene on July 27 and filed a protest on August 14, with a request for confidential treatment. [Source 3] Constellation Energy Generation also moved to intervene. ComEd and PowerHouse Hillwood then exchanged answers through September 17. [Source 1]
According to Utility Dive, the fight centers on credit support. PowerHouse Hillwood contends it met the agreement's initial credit requirement with a $1 posting. Utility Dive's August report says ComEd also canceled a pending retail service agreement at the Illinois Commerce Commission. [Source 4] [Source 5]
Utility Dive quotes Commissioner LaCerte calling the $1 security an "embarrassing legal fiction." His concurrence did not change the outcome. [Source 4]
What the capacity figure means
The 1.8 GW figure comes from Utility Dive's description of the project. The sources we reviewed do not say whether it is utility service capacity, total campus power or critical IT load. It should not be read as IT load, energized capacity or available space. [Source 4]
The reviewed sources do not disclose a tenant, delivery schedule, phasing, or the amount of credit support the agreement ultimately requires.
Buyer analysis
This is our analysis, not a finding in the order. The case shows that a signed transmission agreement can still be contested by the utility on credit terms. FERC's rejection keeps ComEd's cancellation filing from taking effect at FERC, but the contract question now moves to court. That leaves the project's power path unresolved for now.
For tenants and buyers evaluating capacity that depends on a new large load interconnection, the practical questions are about the developer's contracts with the utility. Ask whether the transmission and retail service agreements are in effect, what credit support has been posted and when more is due, and whether any agreement is in dispute before FERC, a state commission or a court.
Utility Dive reports that FERC tied the case to its pending large load interconnection show cause proceedings, with grid operator responses due by mid November 2026. Standard credit terms from that process could reduce this kind of dispute in the future. [Source 4]
