On January 14, 2026, the Federal Energy Regulatory Commission (FERC) issued an order unanimously approving Southwest Power Pool, Inc.’s (SPP) High Impact Large Load (HILL) study process, High Impact Large Load Generation Assessment (HILLGA) process, and associated Load Limited Resource Interconnection Service (LLRIS) effective January 15, 2026.  Under the HILL study process, certain large commercial and industrial loads (i.e., HILLs) will be subject to enhanced study and on-going operational requirements.  The HILL requirements apply to large loads of 50 megawatts (MW) or greater (or 10 MW for loads connected at lower voltage).  The HILLGA process is an optional process to pair one or more new generating resources with a HILL by way of an expedited and separate serial interconnection study process.  HILLGAs are eligible for a new interconnection service, LLRIS, which requires the generator to be in close proximity to the HILL and limits the interconnection service to the amount necessary to serve the associated HILL and to a time period of five years after commercial operation of the new generating resource.

FERC found that SPP’s proposed HILL and HILLGA processes and associated LLRIS are a just and reasonable approach to addressing the region’s significant and unique operational and planning challenges related to the unprecedented growth in large loads, while maintaining the reliable operation of SPP’s transmission system and limiting both operational and financial impacts to other transmission service and interconnection customers.  In a separate concurrence, Commissioner Rosner highlighted SPP’s “innovative” and “pragmatic” approach to interconnecting large loads and supporting economic growth in the region.  Commissioner Rosner also noted that the proposal was a step toward realizing the goals announced in the recent Advance Notice of Proposed Rulemaking  concerning the interconnection of large loads issued by Department of Energy Secretary Chris Wright (for which FERC recently sought comment), including pairing new large loads and new generation to connect them to the grid rapidly and reliably and minimizing costs borne by other customers.  Commissioner Rosner encouraged other transmission providers to consider similar proposals through FPA section 205 filings.   

Key points of the FERC decision include:

HILL Study Process

• Definition of HILL.  FERC approved SPP’s new category of load, termed a “HILL,” which is defined as a new commercial or industrial load or an increase in commercial or industrial load at a single site, which may connect through one or more shared points of interconnection or delivery points, where the new or increased load is either: (1) 10 MW or more, if connected at a voltage level less than or equal to 69 kilovolts (kV), or (2) 50 MW or more, if connected at a voltage level greater than 69 kV.  The definition of HILL excludes Electric Storage Resources.  FERC found that it was reasonable to subject load satisfying such criteria to additional study and operational requirements.    

• Enhanced Study Requirements.  FERC accepted SPP’s enhanced study requirements for HILLs, finding that such studies would provide SPP the information necessary to ensure the reliable integration of HILLs into the SPP transmission system.  

• Ongoing Reliability Requirements.  FERC accepted SPP’s proposed ongoing operational requirements for HILLs, which included, among other things, additional load forecasting requirements, remote capability to disconnect load from the transmission system, installation of Phasor Measurement Units to provide load data in real-time, and ride-through requirements, finding that these requirements ensure reliable operation of the SPP transmission system.

HILLGA Process

• FERC granted SPP an independent entity variation for its proposed HILLGA process, which FERC found provides a flexible, expedited, and separate serial interconnection process that will facilitate the prompt interconnection of generating facilities that are limited to serving a HILL in the same local area. 

• FERC found the more stringent financial commitments, the obligation to satisfy a development milestone earlier in the process, and the requirement that generating facilities enter commercial operation within five years of executing the HILLGA study agreement, among other requirements, would encourage the submission of more commercially ready and less speculative interconnection requests.  FERC also accepted the requirement that the point of interconnection for a HILLGA request must be no more than two substations away from the HILL, as well as the HILLGA substation and transmission line segment requirements.  FERC reasoned that these requirements help to ensure that a HILLGA interconnection will have limited impacts on SPP’s transmission system.

• FERC found that the HILLGA process presents a reasonable approach to address the large load generation needs without disadvantaging requests in SPP’s generator interconnection queue.   FERC pointed out that the HILLGA study process timeline (i.e., 150 days) is a significantly faster timeline than that of the current interconnection process.  FERC also pointed out that the HILLGA process is designed to not drive increased network upgrade costs or risk of restudies for other pending interconnection requests. 

• LLRIS grants limited interconnection service solely to support the associated HILL located in the same local area as the point of interconnection for its generating facility.  FERC found that LLRIS mitigates the generating facility’s impacts on SPP’s transmission system.  A HILL generator interconnection agreement (“HILLGIA”) will automatically terminate five years after the commercial operation date of the generating facility, and any LLRIS granted by the HILLGIA also will correspondingly terminate.  To extend its interconnection past this automatic termination, the HILLGA customer is required to apply for interconnection service under SPP’s existing process.