ERCOT Again Revising Large Load Interconnection Process
Grid Operator Dealing with ‘Unprecedented’ Wave of Requests

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ERCOT has proposed a new method for studying interconnection requests from large load customers.
ERCOT has proposed a new method for studying interconnection requests from large load customers. | © RTO Insider 
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ERCOT proposed revisions to its large load interconnection process just days after a new rule established more rigorous criteria for connecting data centers, bitcoin miners and other power-hungry facilities to the grid.  

ERCOT has proposed revisions to its large load interconnection process just days after a new rule established more rigorous criteria for connecting data centers, bitcoin miners and other power-hungry facilities to the grid.

A new framework is necessary because the new process is already outdated, ERCOT leaders told regulators during the Public Utility Commission of Texas’ Dec. 18 open meeting.

“The processes that we’ve historically used to connect large loads are not providing the clarity or the certainty that’s needed for developers, so we’ve made improvements to those processes,” ERCOT CEO Pablo Vegas told the commissioners. “Those changes, however, are already insufficient to manage the increases and the volume that we are seeing coming through … we think additional changes are needed.”

The ERCOT protocols define a “large load” as one or more facilities at a single site with an aggregate peak demand greater than or equal to 75 MW behind one or more common points of interconnection or service delivery points.

ERCOT had 63 GW of requests from large loads seeking interconnection at the end of 2024. It will go into 2026 with more than 233 GW in the queue, a staggering 269% increase. Data centers account for about 77% of that load.

“What we’re dealing with today is fairly unprecedented,” Vegas said.

The long-term solution is developing the infrastructure to serve the large loads, as Texas is doing. ERCOT, SPP and MISO have all approved extra-high voltage transmission projects of 500- or 765-kV, but those lines will not be completed until the 2030s. (See ERCOT Board Approves $9.4B 765-kV Project.)

Vegas said the current interconnection process “effectively studies the system” at a specific point in time. Within three to six months, an approved interconnection point may not be as suitable as once thought. Projects being pancaked in the same areas create a need to restudy and reconfirm the ability to serve the loads.

That introduces uncertainty and a lack of clarity as to where the customer is in the process, Vegas said.

“When you consider the size, the volume and the dollars that are being invested in these kinds of projects, it’s really an untenable process to continue with that approach,” he said.

Batch Process

To address the issue, ERCOT in February plans to roll out what it calls a batch process that will group together projects ready to be studied. That will establish transmission needs and capacity for the locked-in group of customers.

The first group, Batch 0, will create a foundation and baseline for subsequent batches, building on the assumptions that have changed from the previous group.

“There’s an interim period of time where we have to manage how to connect those large loads in a reliable way and do so expeditiously and in a way that optimizes the capacity that is on the grid today,” Vegas said. “There’s plenty of capacity for growth to connect, so we want to optimize bringing resources into that while the grid is upgraded and infrastructure is built.

ERCOT CEO Pablo Vegas (right) lays out for Texas regulators the proposed interconnection process for large loads. | AdminMonitor

“We think that a batch process would best serve and be able to support getting clarity and transparency to developers,” he said.

ERCOT has retained McKinsey & Company to organize the work and coordinate communications between the grid operator and its stakeholders. Staff plan to talk to transmission service providers (TSPs) and large load customers first to understand their issues and concerns.

At the same time, subject matter experts will develop the framework for the batch study process. General Counsel Chad Seely said ERCOT will use the Large Load Working Group as a forum to “check in” and the member-led Technical Advisory Committee to provide any updates. He said staff will also update the PUC during its January open meetings, bringing a proposal on the batch study framework to the commission in February.

“There’s clearly a pressure to move quickly and support the economic growth that’s coming our way,” Vegas said, emphasizing that input from affected stakeholders will be “critical to doing this accurately.”

The work will include modifying ERCOT’s existing large load interconnection processes. The grid operator on Dec. 15 introduced a number of changes to the interim process that has been in place since 2022 with a revision to the Planning Guide (PGRR115).

The PGRR applies time limits to ERCOT’s review of TSP interconnection studies and allows large load projects to be included in other customers’ studies. With the change, ERCOT can evaluate large load projects in a quarterly stability analysis. TSPs are also required to submit a load-commissioning plan establishing the schedule for energizing each phase of the load’s project and update the schedule as the facilities serving the load are identified and eventually constructed.

Vegas likened the process to a restaurant that doesn’t accept reservations but promises a table to customers for dinner at 7 p.m. However, before then, other customers come in and end up with the available tables.

“That’s effectively the way the transmission study process works today,” Vegas said.

“Maybe we’re just so popular now that we have to start having a reservation system,” Commissioner Courtney Hjaltman said.

Vegas said milestones need to be developed to hold capacity committed to the transmission system until a project is built because serious projects ready to develop will be queued up. When milestones aren’t met, a process will be needed to reclaim the transmission capacity for subsequent batches, he said.

‘Whatever the Kitchen Cooks up’

ERCOT plans to process several batches each year, with the entire process expected to last three to five years “until significant infrastructure gets built.”

The PUC has opened a docket in the proceeding (59142) to capture comments from stakeholders and serve as a document depository. Several large load entities wasted little time in filing comments.

Schaper Energy Consulting said ERCOT’s “abandonment” of PGRR115 and “sudden pivot” to an undefined batch study procedure “threatens to undermine transparency and discard stakeholder-approved protocols.”

“It could erase years of development progress. ERCOT’s unannounced reversal introduces severe regulatory risk and undermines the certainty essential for continued investment,” the company wrote. “An abrupt regulatory change without sufficient transparency or thorough stakeholder engagement is not aligned with the stable regulatory environment for which Texas has historically been recognized and risks eroding confidence in ERCOT.”

Referencing Vegas’ restaurant analogy, Schaper said the batch study process “defies the logic of their own metaphor.”

“It is akin to a manager handling a dinner rush by forcing eager patrons into the parking lot to wait for whatever the kitchen cooks up,” the company said.

Google and energy project developer Lancium filed joint comments warning that the PUC needs to maintain cohesion across its proceedings related to Senate Bill 6. The legislation was signed into law earlier in 2025 and requires the commission to determine a cost allocation for large loads to ensure they’re paying their fair share of infrastructure expenses. (See Texas PUC Releases Rulemakings for Large Loads.)

“Without cohesion across proceedings, Texas risks under-planning the system, misallocating financial commitments and slowing substantial economic development,” Google and Lancium said.

Public Utility Commission of Texas (PUCT)Transmission Planning

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