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ERCOT Large Load Interconnection

Every data center that draws power from the Texas grid has to get in line first. That line is the ERCOT large load interconnection process, and in the space of two years it went from a routine utility procedure to the single biggest bottleneck in the American AI buildout. The queue now holds about 474 GW of requests against a grid whose record peak demand is near 91 GW — more than five times the entire system, with roughly 90% of it data centers.

That mismatch is the reason the largest campuses in Texas build their own power and skip the queue entirely. Understanding the interconnection process is how you understand why behind-the-meter generation became the default.

The 75 MW line

ERCOT draws its bright line at 75 MW of peak demand at a single site. Cross it and a project is a large load, subject to the new batch interconnection framework, SB 6 curtailment rules, and study fees. Stay under it and a facility connects through its local utility — Oncor, CenterPoint, AEP Texas, or TNMP — under the same standard that applied before the rules changed.

The threshold captures exactly the projects driving the crisis: hyperscale data centers, AI training campuses, crypto mining, and large industrial plants. A single modern training campus can draw more than a gigawatt, more than ten times over the line.

Why the old process broke

Until 2026, each transmission provider studied large loads one at a time and sent the results to ERCOT for approval. That worked when large loads were occasional. It collapsed when data center requests arrived by the hundreds: the queue ballooned from about 63 GW in late 2024 to over 400 GW, and studying each project in isolation could not account for the collective strain of dozens of gigawatt-scale loads landing on the same transmission network at once.

The deeper problem was credibility. A one-at-a-time queue treats a signed, financed campus and a speculative land option as equals, first-come first-served. Nobody could tell how much of the 400-plus GW was real. Sorting the committed projects from the placeholders became the central task.

Batch Zero

The PUCT approved ERCOT's answer, called Batch Zero, on June 18, 2026. It replaces one-project-at-a-time review with a single system-wide study of every qualifying large load at once, allocating available transmission capacity across the whole batch and producing an actionable plan for the upgrades needed to serve them.

It is a one-time, transitional process — a way to clear the backlog without re-running engineering studies for every new entrant. To qualify, a project has to prove it is real, not announced: site control, an executed transmission service agreement, and readiness to energize within roughly 18 to 24 months. ERCOT sorts the results into committed base load, loads studied within Batch Zero, and projects deferred to a later process. The study also raised the technical bar, requiring large loads to ride through grid disturbances rather than trip offline and worsen an emergency.

Batch Zero was scheduled to deliver its first capacity allocations to each project by April 9, 2027. That timeline is now interrupted.

SB 6 and the kill switch

The interconnection rules sit on top of Senate Bill 6, the 2025 law that rewrote how large loads join and operate on the grid. Its most consequential provision is mandatory curtailment: data centers and other non-critical loads of 75 MW or more must accept being ramped down or switched to backup generation during a firm load-shed emergency, so they help rather than hurt reliability when the grid is short. SB 6 also created interconnection study fees, disclosure and cost-sharing rules, and the co-location protocols that govern pairing a data center with an existing power plant.

The intent, as one utility regulator put it, is to keep large loads from drinking the milkshake of every other customer on the system. Curtailment is the enforcement mechanism, and it is another reason operators prefer to bring their own power: a behind-the-meter campus is far less exposed to a grid kill switch it does not depend on.

The pause

On August 3, 2026, Governor Abbott halted Batch Zero and ordered ERCOT and the PUCT to audit every project in it before any can energize. The moratorium freezes the process described above until roughly 300 projects are verified for power draw, water use, public incentives, community impact, and ownership. ERCOT expects to finish by December 10, 2026, and interconnections cannot resume until it does.

The audit's real output will be a number nobody has had before: how many of those projects were ever going to be built. Batch Zero represents as much as 200 GW of potential capacity by 2032, and the count ruled ineligible will be the first honest measure of how much of the Texas queue is real.

Why it drives the architecture

The interconnection process explains the shape of the Texas buildout more than any other single factor. A queue five times the size of the grid, a multi-year wait, a mandatory curtailment switch, and now an audit-driven freeze — together they make grid power the slowest and least certain input a data center has to secure.

So the largest builders stopped asking for it. Fermi's Project Matador, Google's Meitner, AWS at GW Ranch, and Microsoft's Project Kilby all generate on site and connect to the grid only at the margin, if at all. Everything in this process — the queue, the 75 MW line, Batch Zero, SB 6, the pause — is the constraint that behind-the-meter generation was built to route around.

Last updated September 11, 2026. Batch Zero is paused pending the state audit due December 10, 2026; first capacity allocations were scheduled for April 9, 2027. Check ERCOT market notices for the current state.