On June 18, 2026, the Federal Energy Regulatory Commission (FERC or the Commission) issued an order to Midcontinent Independent System Operator, Inc. (MISO) directing MISO and MISO transmission owners to show cause as to why MISO’s tariff should not be found to be unjust and unreasonable (Midcontinent Independent System Operator, Inc., 195 FERC ¶ 61,212 (2026) (Order)) because it fails to sufficiently:
- Address the application process, study process and ongoing operational requirements for customers seeking transmission service for large loads.
- Mitigate the risk of cost shifting among transmission customers due to large loads, including providing transparency regarding the assignment of network upgrades and requiring a pro forma cost recovery agreement that would ensure that large load customers bear the risks and costs of network upgrades needed to provide them with transmission service.
- Include provisions for the rates, terms and conditions of service for co-location arrangements.
- Include flexible transmission service for large loads willing to limit their use of the transmission system.
- Provide generation resources the ability to be studied in a manner that reflects the operational dynamics of serving either an “electrically proximate large load” or a co-located load of 50 MW or greater.
MISO and its transmission owners are required to submit a response justifying the existing tariff language or proposing tariff revisions addressing FERC’s concerns within 60 days (by August 17, 2026). Order at P 33. The Order also directs MISO to file an informational report within 30 days addressing “how MISO intends to ensure that adequate generation will be available to serve existing and new large loads.” Id. at P 34. Interested entities may respond to the filings made by MISO and the MISO transmission owners within 30 days of those filings, addressing the same concerns. Id. at P 35. The Commission will also allow MISO and the MISO transmission owners to seek limited abeyance of up to 90 days to allow them time to work through the stakeholder process to develop a filing under Section 205 of the Federal Power Act (FPA) to respond to the issues raised in the Order. Id. at P 37.
The following sections provide a more detailed overview of the Commission’s discussion in each area identified by the Commission.
Transmission Service for Large Load Customers
The Order preliminarily finds that MISO’s tariff appears to be unjust and unreasonable because it does not sufficiently address how MISO and/or the MISO transmission owners will timely study the provision of transmission service to customers on behalf of large loads. Id. at P 39. The Order first addresses jurisdictional concerns for the Commission as to transmission service for large loads and then turns to concerns with MISO’s tariff.
While the Order recognizes that efforts at the state level to address large loads are encouraging, certain aspects of the process for integrating large loads onto the transmission system fall squarely within the Commission’s exclusive jurisdiction. Id. at PP 42-43. The Order finds that “it is within the Commission’s exclusive authority to ensure that transmission provider and/or transmission owner tariffs include sufficiently clear and consistent provisions governing how transmission service to Eligible Customers on behalf of large loads interconnecting to the transmission system will be studied, including whether new or upgraded transmission facilities are necessary to provide the requested transmission service.” Id. at P 43. The Commission explains that it is exercising its jurisdiction here to “ensure that the process by which jurisdictional transmission providers and/or transmission owners will study the provision of jurisdictional transmission service to Eligible Customers on behalf of large loads interconnecting to the transmission system … is just and reasonable and not unduly discriminatory or preferential.” Id. at P 47. But the Order declines to “comprehensively address the Commission’s jurisdiction over other aspects of the addition of large loads to the transmission system at this time.” Id.
While the Order recognizes that MISO has existing load integration processes, it finds those processes “are not described in the Tariff with the degree of clarity and specificity necessary to ensure that the transmission provider can mitigate operational risks of providing transmission service to Eligible Customers on behalf of large loads, given their impact on the transmission system, avoid disputes regarding how studies are conducted, deter speculative or duplicative requests for transmission service by Eligible Customers on behalf of large loads, and help avoid excessive and unnecessary Network Upgrades.” Id. at P 49.
The Order identifies four areas where it believes that the existing tariff provisions fall short: (1) the lack of a definition of large load that is sufficient to capture the unique challenges provided by such customers; (2) the absence of sufficiently clear and consistent tariff provisions establishing the application and study procedures for the provision of large loads, including readiness requirements; (3) insufficiently stated ongoing operational requirements for transmission customers serving large loads necessary to ensure reliable operation of the transmission system; and (4) the lack of pro forma provisions in transmission service agreements to memorialize these terms. Id. at P 57.
1. Definition of Large Load
The Order states that the definition of large load, including a load size and voltage threshold, should be based on the characteristics of the transmission system, but that a reasonable definition of large load could be “a new, commercial or industrial customer, located at a single site behind one or more points of interconnection, and that has a peak load of 50 MW or greater, interconnects to the transmission system at a voltage level of greater than 69 kV, and is not part of a co-location arrangement.” Id. at P 58. The Order notes that this aligns with the proposed definition in MISO’s Large Load Working Group. Id.
2. Application Process and Study Procedures
The Order states that the tariff currently lacks a sufficiently clear application and study process for transmission service to large load. The Order requires MISO to explain whether its tariff is just and reasonable despite lacking the following provisions:
- An application process that accepts Eligible Customers’ applications for transmission service on behalf of large loads on a rolling basis.
- A non-refundable application fee and sufficient readiness requirements that escalate at distinct phases of the study process to deter duplicative or speculative requests for transmission service (e.g., meaningful milestones and/or financial commitments).
- Information and data requirements that Eligible Customers must submit to MISO and/or the MISO transmission owners regarding the characteristics of the large load on behalf of which the Eligible Customer is taking transmission service, including disclosure to MISO of any substantially similar pending transmission service requests on behalf of the same large load customer.
Id. at P 59. The Commission also states that the tariff does not clearly and consistently require MISO or the MISO transmission owners to conduct studies that evaluate the transmission system’s ability to withstand risks observed from large loads and that consider the unique operational characteristics of large loads that are willing to limit their energy withdrawals under certain conditions. Id. at P 60.
The Order also finds that the tariff may be unjust and unreasonable because it does not include clear provisions requiring the evaluation of alternative transmission technologies, which can add more capacity to the existing transmission system quickly and increase costs to the detriment of customers. Id. at P 61. In addition to evaluating such technologies, the Commission finds that study reports that determine traditional network upgrades are required instead of alternative transmission technologies should include a “clear demonstration of why alternative transmission technologies are not feasible.” Id. at P 62.
Finally, the Commission finds that the study processes contemplated in the Order should culminate in a study identifying any direct assignment facilities and network upgrades an Eligible Customer is responsible for and take “no more than 60-90 calendar days to complete.” Id. at P 63.
3. Ongoing Operational Requirements
The Order finds that the MISO tariff appears to be unjust and unreasonable because it does not include provisions to mitigate operational risks associated with large load, including provisions that require transmission customers to provide MISO hourly forecasts, telemetry data and other data to provide MISO with sufficient visibility into the operation of large loads. Id. at P 64. The Commission also expresses concern that the tariff does not require transmission owners to install—at the expense of the relevant transmission customer—equipment to mitigate the risks of large loads, including equipment that allows MISO to monitor large loads for impacts of fast-ramping large loads that may not be capable of being captured by conventional data acquisition systems or equipment that allows MISO to disconnect large loads when necessary to maintain reliability. Id. The Commission further expresses concern that the tariff does not specify ramp rate or ride-through requirements that transmission customers taking service on behalf of large loads must comply with or specify control technologies and protection systems required to limit a customer’s withdrawal from the transmission system as appropriate. Id.
4. Pro Forma TSA Provisions
Finally, the Order raises concerns that MISO’s tariff “lacks pro forma provisions in a transmission service agreement between MISO and the transmission customer taking transmission service on behalf of a large load” that reflect ongoing operational requirements for Eligible Customers taking service on behalf of large loads. Id. at P 65. The Order directs MISO to explain whether its tariff remains just and reasonable without such pro forma provisions in a transmission service agreement, or to propose revisions to include pro forma provisions memorializing the ongoing operational requirements in a transmission service agreement between MISO and the transmission customer.” Id.
Cost Shifting Issues
The Order finds that the MISO tariff lacks adequate mechanisms to mitigate the risk of cost shifting among transmission customers with respect to the integration of large load. Specifically, the Commission finds that (i) additional transparency about the assignment of network upgrade costs associated with providing transmission service to large loads is needed, and (ii) MISO should require large load customers to execute a cost recovery agreement requiring them to bear the risk and cost responsibility for the network upgrades required to serve them. Id. at P 67.
1. Cost Data Transparency
To promote transparency regarding the network upgrades necessary to accommodate large load, FERC directs MISO to make available “robust, accurate, systematic, and searchable” data regarding the cost of network upgrades required to provide transmission service to large load customers on a single location on its website. Publicly available data would include (1) the aggregate amounts of proposed large load additions in the MISO footprint, (2) the planned network upgrades needed to provide service to large load customers, identified by type of equipment and network upgrade for each transmission service request, and (3) cost estimates for the network upgrades. Id. at P 77. FERC explains that centralized information concerning network upgrades required to serve large loads will also help inform stakeholders at the state and local level to address affordability and other challenges posed by the integration of large loads. Id. at P 73.
2. Cost Recovery Agreements
FERC finds that MISO’s tariff does not adequately mitigate the risk of cost shifting among transmission customers, which may result in unjust and unreasonable transmission service rates. Specifically, FERC states that additional measures are needed to protect other wholesale transmission customers from “stranded” transmission costs resulting from network upgrades constructed for large load projects that either do not ultimately materialize or that operate at a lower demand than anticipated. FERC expresses concern that the MISO tariff does not require cost recovery agreements among MISO, the relevant transmission owner, and the large load customer that require the customer to cover the costs incurred to provide the requested transmission service, including the costs of any needed network upgrades. Id. at P 80.
To address this issue, FERC directs MISO to establish a pro forma cost recovery agreement between MISO, the relevant transmission owner, and the large load customer that ensures that the large load customers bear the risk and responsibility for all costs (including network upgrade costs) incurred to provide transmission service. Id. at P 82.
- FERC preliminarily finds that the minimum contribution required should be based on the level of FERC-jurisdictional transmission service, in MW, requested by the large load customer, although it acknowledges that there may be other just and reasonable methods for determining the minimum contribution, including methods that account for potential timing differences between when costs are incurred to develop network upgrades and the pace at which the large load energizes at its full level of requested service. Id. at P 84.
- FERC states that a credit support or other financial security requirement sufficient to secure the customer’s obligations under the cost recovery agreement is necessary, but notes that security posted by the customer as part of a retail agreement may be included to avoid creating duplicative credit support obligations. Id.
Treatment of Co-Location Arrangements and Load with Behind the Meter Generation
The Order finds that MISO’s tariff does not contain sufficiently clear and consistent provisions addressing the rates, terms and conditions that apply to co-location arrangements and transmission services available to large load customers that are willing and able to limit energy withdrawals from the grid under certain conditions. Id. at P 94. FERC is particularly concerned that the absence of provisions addressing transmission and ancillary service rates for large load customers creates the potential that such customers may not pay for wholesale transmission services that they receive, violating the cost causation principle. Id. at PP 95-96.
FERC thus directs MISO to propose tariff revisions establishing the rates, terms, and conditions that apply to co-location arrangements, noting that MISO is currently considering reforms related to new transmission services through its stakeholder process, which may fully or in part address the Commission’s concerns. The issues requiring clarification or modification include:
- How interconnection customers serving co-located load may use generator interconnection processes in MISO’s tariff to facilitate their co-location arrangements.
- For interconnection customers serving co-located load, designation of the specific Eligible Customer taking transmission service on behalf of the co-located load under the tariff for purposes of assessing charges, including the appropriate charges for wholesale services that should apply to such Eligible Customers.
- Providing additional information about the existing rules and studies applicable to co-location arrangements to ensure clarity for how interconnection customers may seek to serve co-located load.
- Ensuring that Eligible Customers serving co-located load pay for the use of regulation and black start services on a gross demand basis.
Id. at PP 94-102.
New Flexible Transmission Service
FERC preliminarily finds that MISO’s tariff may be unjust and unreasonable because it fails to offer transmission service options tailored to “flexible” large loads—i.e., loads that are not co-located with generation, but that are willing and able to limit their energy withdrawals under certain conditions. Id. at P 104. Based on the record developed in the Advanced Notice of Proposed Rulemaking (ANOPR) on large load interconnections, the Commission concludes that existing services (network integration transmission service and firm or non-firm point-to-point transmission service) do not adequately reflect the operational reality that some large loads are willing and able to limit their withdrawals and therefore may not require the same level of transmission capacity or upgrades as inflexible load. Id. FERC emphasizes that allowing Eligible Customers serving such loads to select transmission services aligned with actual usage would better match costs to benefits, could reduce inefficient or premature network upgrades, and facilitate more timely interconnection of large loads. Id. Accordingly, FERC expresses concern that MISO does not offer interim non-firm network service or contract-demand-based transmission services (firm or non-firm) designed for flexible loads and directs MISO to either justify its tariff’s failure to include these services or propose revisions to incorporate such services. Id. at PP 104-105.
Interconnection Service for Electrically Proximate Large Load and Co-Located Load
The Commission finds that it has an obligation to use its “exclusive jurisdiction over generator interconnection to ensure the availability of generator interconnection processes specifically tailored to the unique operational characteristics of generating facilities dedicated to serving electrically proximate large loads and co-located loads.” Id. at P 111. For the purpose of the Order, the Commission defines “electrically proximate large load” as a large load that is sufficiently electrically close to the interconnection customer’s requested point of interconnection, such that the impact on the transmission system of the combination of the generating facility and the load, with the exception of the transmission facilities between the two, will be effectively the same as if they were located at the same substation (e.g., large load that is located no more than two substations away from the generating facility). Id. at P 112.
The Order finds MISO’s tariff appears to be unjust and unreasonable because it does not address interconnection reflecting the operational dynamics of an electrically proximate large load or co-located load. Id. In particular, it notes that the MISO tariff does not include generator interconnection procedures that would allow a customer to make a commitment to limit its output to match the hourly forecast of an electrically proximate large load or large co-located load or to implement control technologies and protection systems that ensure that the injection from the resource does not exceed the limit prescribed by its interconnection agreement. Id. at P 113. The Commission explains that “[w]here a generating facility’s output is matched to the demand of the electrically proximate large load or large co-located load or if the generating facility’s output is limited to ensure no new injection, the impacts to the transmission system of interconnecting the generating facility to serve that electrically proximate large load or large co-located load may be limited, thereby potentially reducing the need for Network Upgrades, which can accelerate the generator interconnection process.” Id. Absent operational procedures that account for the unique operational dynamics of a generator and the load that it services, the Commission finds that new “shovel-ready generating facilities may face unnecessary delays in reaching commercial operation under current generator interconnection processes and will be able to serve the immediate demand of new large loads or large co-located loads.” Id.
The Order highlights Southwest Power Pool, Inc.’s (SPP) High Impact Large Load Generator Assessment (HILLGA) process as one example for how to address the Commission’s concerns, although it emphasizes that the Commission is not requiring MISO to adopt an identical process. Id. at P 115. The Commission explains that a potential alternative to the HILLGA model would be to “develop a generator interconnection study process that would allow the use of existing [energy resource interconnection service (ERIS)] or [network resource interconnection service (NRIS)] of an existing generator to connect a new generating facility and a new large load behind the same point of interconnection of the existing generator with necessary control technologies and/or protection systems . . . that ensure that the net injection does not exceed the amount in the existing generator interconnection agreement.” Id. at P 116.
Thus, the Commission directs MISO to address in its response whether its tariff remains just and reasonable without provisions that establish:
- A new generator interconnection process and new interim generator interconnection service that reflect an interconnection customer’s commitment to limit a generating facility’s output to match the hourly forecast of an electrically proximate large load or co-located load.
- A generator interconnection process that allows an existing generator’s ERIS or NRIS to be used to connect a new generating facility and a new large load behind the same point of interconnection of the existing generator with necessary control technologies and/or protection systems, which may include a special protection scheme, that ensures that the net injection does not exceed the amount in the existing generator interconnection agreement.
- A new generator interconnection service that allows a new generating facility and new large co-located load seeking to interconnect behind the same new point of interconnection with necessary control technologies and/or protection systems, which may include a special protection scheme, to ensure that there is no injection to the transmission system.
Id. at P 118. Importantly, with respect to the first example listed above, the Commission notes that a generator that receives service through a coordinated study process to serve an electrically proximate load should be of an interim nature until the customer receives ERIS or through an existing interconnection process. Id. at P 115. At the same time, the Commission states that it may be reasonable to provide permanent service to a generator serving co-located load because “there will be no injections onto the transmission system and therefore it does not present operational or planning risks for reliability.” Id. For the other two examples, the Commission explains that the service could be either interim or permanent and that the approaches outlined in the final two examples may not be mutually exclusive. Id. at P 118.
Because the generator interconnection process does not convey transmission service, the Commission encourages MISO to consider what type of transmission service an eligible customer would need to take on behalf of electrically proximate large loads or large co-located load. Id. at P 119. FERC notes its previous determination in its PJM co-location order that an eligible customer must take transmission service on behalf of co-located load that will not withdraw energy from the transmission system, even if it is 0 MW. Id.
Informational Report and Briefing Questions
Finally, the Order directs MISO to file an informational report within 30 days “on any proposals under consideration in its stakeholder process to address the issue of resource adequacy to serve new large loads.” Id. at P 122. FERC also directs additional briefing on issues related to large load integration including:
- How MISO and the MISO transmission owners should protect existing commercial arrangements proposing tariff revisions in response to the Order, including suggestions for a reasonable implementation period to minimize disruption to existing arrangements and a reasonable amount of time to finalize ongoing agreements that are nearing completion as of the date that responsive tariff provisions are filed with FERC.
- Potential impacts on regional and local transmission planning that would arise from the introduction of the new transmission services FERC identifies in the order.
- Potential structures for cost recovery agreements to prevent unjust and unreasonable cost shifts among transmission customers related to network upgrade costs required for large loads, including proposals for minimum levels of cost recovery and financial security required from a large load customer.
- Whether further evaluation of alternative transmission technologies beyond those the Commission has discussed in the Order is warranted.
- Any filings or tariff changes in response to the Order should also address:
- To what extent would MISO allow an interconnection customer’s generating facility serving electrically proximate large load or large co-located load to participate in MISO’s energy and ancillary services market, and if MISO were to allow them to participate, what restrictions or mitigation would MISO apply?
- To the extent that MISO plans for the electrically proximate large load or large co-located load associated with an interconnection customer’s generating facility for resource adequacy purposes, would MISO account for the generating facilities serving electrically proximate large load or large co-located load in the resource adequacy construct? If applicable, would MISO allow the generating facilities serving electrically proximate large load or large co-located load to participate in MISO’s capacity market? If so, would MISO accredit these generating facilities using the same method as other MISO generating facilities?
See id. at PP 123-127.
Concurrences to the Order
Each Commissioner also issued a brief concurrence to the six show cause orders:
Chairman Swett
Chairman Swett highlights that the record prompted by the ANOPR “leaves no doubt that most of the markets (and their existing rules) are inherently slow and prohibitive of the dexterity necessary to adapt to and power societal evolution[.]” Order (Swett, Chairman, concurring at P 2). Her concurrence explains that individualized orders for each market—as opposed to a single rulemaking—is the best approach for two reasons: (1) that the ANOPR and subsequent developments suggest that individual show cause proceedings are better tailored to addressing the unique circumstances of each market and (2) individual show cause orders will allow the Commission to act more quickly. Id. at PP 4-10.
Commissioner Rosner
Commissioner Rosner’s concurrence identifies four key pillars that provide a foundation for durable reform: (1) protecting consumers, (2) safeguarding reliability, (3) enhancing transparency and (4) fostering innovation. Order (Rosner, Comm’r, concurring at P 2). Commissioner Rosner asserts that the show cause orders protect consumers because they include key provisions that promote affordability, including requirements addressing cost recovery agreements and consideration of grid enhancing technologies. Id. at PP 3-4. The show cause orders safeguard reliability because they ensure that regional transmission organizations (RTO) and independent system operators (ISO) use study procedures and operational requirements that reflect the unique considerations of large loads. Id. at P 5. The show cause orders enhance transparency because they provide data to regulators and customers on how large loads impact bills. Id. at PP 7, 8. The show cause orders also address speculative load interconnection requests by establishing escalating readiness requirements in the study process. Id. at P 9. Finally, the orders foster innovation because they promote flexible transmission services, recognize that large loads that are not co-located can promote efficiency by limiting their withdrawals from the grid, and embrace the unified study of large loads and generation that are electrically proximate. Id. at P 13.
Separately, Commissioner Rosner underscores that FERC cannot act alone and that partnership with the states is essential. Id. at P 15. Commissioner Rosner asserts that the show cause orders respect the existing jurisdictional framework provided by Congress and affirmed by the Supreme Court and these orders are the beginning of a dialogue with RTOs/ISOs to address the challenges facing their regions. Id. at PP 15-16.
Commissioner See
Commissioner See’s concurrence highlights two principles present throughout the show cause orders: that these issues extend beyond the Commission and that affordability is key. Order (See, Comm’r, concurring at PP 3-4, 6). Creating efficient large load interconnection is a task for FERC, other federal agencies, the states, RTOs/ISOs and utilities. Id. at P 4. The concurrence recognizes the value in independent approaches and strongly encourages proposals under Section 205 of the FPA. Id. Commissioner See says it is critical to respect the jurisdictional arrangement between FERC and the states and that today’s actions are designed to support further state efforts addressing large load, not override them. Id. at P 5. Although FERC lacks authority over all factors that impact electricity prices at the retail level, the show cause orders provide the states all relevant informational about Commission-jurisdictional costs. Id. at P 6. Commissioner See seeks continued feedback from the states on the cost transparency measures in the orders. Id. The concurrence also addresses where FERC can directly address cost responsibility, including using grid enhancing technologies. Id. at P 8. Commissioner See also addresses the novel questions for cost shifting that large load interconnection present, including mitigating the risks of stranded costs. Id. at P 9.
Commissioner Chang
Commissioner Chang emphasizes the importance of building actionable records in the show cause proceedings, particularly as to customer protection, transmission service, and alternative transmission technology reforms. (Chang, Comm’r, concurring at P 1). The concurrence stresses the need for active stakeholder participation because of the ex parte restrictions caused by the Commission acting under Section 206 of the FPA. Id. at P 4. The records in these proceedings will differ, and as such, the required changes in each region will be tailored to that region’s needs. Id. at P 5. Because the FPA is fundamentally a consumer protection statute, Commissioner Chang says FERC needs to pursue meaningful consumer protection. Addressing how costs will appropriately be assigned is at the core of the show cause orders. Id. at PP 6-9. Commissioner Chang also indicates that the introduction of new transmission service is complex and could create unforeseen reliability risks and FERC must find the proper balance between costs of investments and reliability. Id. at PP 10-11. Finally, the concurrence underscores the impact of evaluating advanced transmission technologies. Id. at P 12.
Commissioner LaCerte
Commissioner LaCerte says that the country is “at an inflection point in the history of American energy infrastructure.” Order (LaCerte, Comm’r, concurring at P 1). Commissioner LaCerte’s concurrences sets forth his expectation that each of the RTOs and ISOs will timely submit their proposals to address the concerns of the show cause orders or else he is prepared to “play jurisdictional hardball” to any deficient responses. Id. at P 6. The concurrence also asks that state commissions review their large load provisions to ensure that ratepayers are insulated from the negative impacts of data center growth. Id. at P 2. Commissioner LaCerte notes the high stakes for the industry at this time and discusses how the ANOPR responses lead to the Commission’s region-specific approach. Id. at PP 4-5. While the Commission has exercised restraint thus far in addressing these issues, Commissioner LaCerte points to the broad jurisdiction the Commission has over transmission and asserts that it will not hesitate to use in these proceedings to ensure that the Commission achieves its objectives. Id. at P 6.
