Part A or Part B? Form W or Not? The Keentel Guide to PUCT Generating Capacity Reporting and ERCOT's PCLR Election for Large Loads

If you're developing a large load in Texas with on-site generation — a BYOG data center, a campus with gas turbines and batteries, a mining operation with solar behind the fence — you will eventually meet two documents with confusingly similar names:

The PUCT Generating Capacity Report, whose Part A and Part B decide how the state tracks your generation — as a commercial power producer or a self-generator.

ERCOT's Form W, whose Part A and Part B are the two acts of electing the Provisional Controllable Load Resource (PCLR) pathway in the batch interconnection process.

They come from different regulators, serve different purposes, and follow different calendars — and both carry consequences for getting them wrong. This guide explains each one, how they interact for combined generation-and-load projects, and answers the questions we hear most, in depth.

Part One: The PUCT Generating Capacity Report — Part A and Part B

What it is and where it comes from

The Generating Capacity Report (GCR) lives in PUC Substantive Rule § 25.91, adopted alongside the market-power rules (§ 25.90 and § 25.401) to implement PURA §§ 39.154–39.157 from Texas's electric restructuring era. Its original purpose is market surveillance: the Commission uses GCR data to calculate each owner's share of installed generation capacity in a power region, which feeds the statutory limits on generation market concentration. That heritage explains the form's structure — it is fundamentally asking who owns how much capacity, and how much of it reaches the market.

Part A versus Part B — the classification that frames your filing

Part A — Power Generation Companies (PGCs).

This is the lane for commercial entities whose business is generating and selling electricity: registered PGCs whose capacity participates in the wholesale market. The associated data tracks generation capacity connected to transmission or distribution systems and available for sale into ERCOT or other reliability regions. Part A filers sit inside the broader PGC regulatory framework — registration under § 25.109, which itself incorporates the § 25.91 reporting obligation.

Part B — Self-Generators.

This lane covers industrial, commercial, or private entities that own generating facilities primarily for their own consumption. The data focus flips: how much capacity serves on-site load, and how much excess might be available to the grid.

The data fields both lanes feed.

Regardless of part, the form's tables collect the metrics the Commission's market calculations need: connected capacity (total MW connected to transmission or distribution), self-consumption capacity (MW dedicated to the owner's internal use), future capacity (expansions or new facilities entering service within 12 months), and available-for-sale capacity (what's left for the market). The reports are filed annually, on the Commission's prescribed form with an affidavit.

The capacity rating rules (§ 25.91(f)).

The rule standardizes how hardware is valued so market-share math is consistent: conventional generators at summer net dependable capability; non-dispatchable renewables (wind, solar) at their actual peak-season contribution or nameplate treatment as the rule prescribes; and facilities entering service within 12 months at nameplate. For a BYOG campus, this matters practically — your two combined-cycle blocks, your BESS, and any on-site solar can each carry a different rating basis in the same filing.

The nuance most summaries miss: the "offer for sale" hinge

Here is where careful reading pays

When § 25.91 was adopted, the Commission fought through exactly the question BYOG developers ask today: must a pure self-generator file at all? Utilities argued the rule should reach all connected generation including self-generation and cogeneration; industrial consumers argued generation not offered for sale can't affect market power and shouldn't be reported. The Commission anchored the obligation to the statute: PURA § 39.155(a) requires entities that own generation facilities and offer electricity for sale in the state to file generating capacity reports. Historically, that made "do we offer power for sale?" the pivotal question — and made truly consumption-only generation arguably reportable differently than merchant capacity.

Why you cannot rely on the historical answer alone: the 2025 legislative session (SB6 and related PURA amendments on large loads and behind-the-meter generation) redrew parts of this boundary, and ERCOT's own June 2026 public statements note that even fully islanded facilities "may still be subject to registration requirements with the PUCT." The direction of travel is unmistakable — more visibility into self-supplied large loads, not less. Before classifying your project, pull the current § 25.91 text, the current GCR instructions, and any post-SB6 registration rules. This is precisely the kind of filing where a one-year-old memo is a liability.

Where a WLPUN/BYOG project usually lands

The classification question for a project like a 1,000 MW campus with 1,150 MW of on-site combined-cycle generation is rarely a clean "Part B self-generator." If the generation registers as an ERCOT resource, can export, and sells energy or ancillary services in any hour, it walks and talks like PGC territory — typically meaning PGC registration (§ 25.109) and Part A treatment, with large self-consumption reported in the fields built for exactly that hybrid.

A genuinely islanded or never-exporting configuration presents differently. The honest answer is that classification is a project-specific legal-and-engineering determination — generation registration status, export capability, market participation, and PUN structure all feed it — and it should be made deliberately, on the current rules, before the first filing is due, not after.

Part Two: ERCOT's Form W — the PCLR Election in Two Acts

Different regulator, different purpose, same "Part A / Part B" vocabulary — which is why we untangle it here.

Form W is how a Studied Load in ERCOT's batch interconnection process elects the PCLR pathway: permission to consume above its firm allocation (LPC) up to its full request (MPC), in exchange for placing that above-firm consumption under ERCOT's real-time dispatch — including the five-minute bid caps ERCOT uses to manage local transmission constraints — until a study-established Exit Date.

Form W Part A — the Declaration of Intent

Completed, signed, and notarized by the developer and submitted to the interconnecting utility with the batch eligibility package (July 10, 2026 for Batch Zero; the utility forwarded it to ERCOT by July 24). Part A is a binding commitment to the pathway and must specify the project's minimum LPC limits for each study year. One flexibility ERCOT confirmed: a project applying for base load classification could file Part A conditionally, as a fallback in case it was classified as studied load — if the project qualified as base load, ERCOT simply disregards the form.

Form W Part B — acceptance

Due by March 1, 2027: the developer accepts the study's actual LPC amounts and Exit Date and executes the interconnection agreement. The consequence of missing Part B is written without mercy — the project is deemed to have withdrawn, is dropped from the refinement study, and waits for a future batch.

The obligations the election buys

Registration as a Controllable Load Resource (telemetry, dispatch systems, a qualified scheduling entity), SCED dispatch compliance at all times, no ancillary services during the provisional period, and curtailment exposure on the above-LPC layer that is entirely locational — which is why a curtailment-risk study against your specific point of interconnection belongs before the notarized signature, not after.

Part Three: How the Two Regimes Interact for a BYOG Project

A combined generation-and-load campus can touch both regimes at once, and the interactions are worth mapping:

Different clocks

The GCR runs on an annual PUCT filing calendar; Form W ran on the batch process's one-time gates (with Batch 1's window expected to open Summer 2027 under the ongoing batch rule). Missing the annual report is a compliance problem; missing Form W Part B is a project-existence problem.

Different questions, shared facts

The GCR asks what generation do you own and who gets its output; Form W asks how flexible is your load. But both draw on the same project facts — generation registration, export capability, self-consumption levels, PUN structure — so inconsistency between filings is both easy to create and easy for regulators to spot. Your GCR's self-consumption figures, your ERCOT resource registration (RARF), your WLPUN or PCLR election, and your Load Commissioning Plan should tell one coherent story.



Pathway logic differs by project type

A BYOG project's natural batch election is usually WLPUN (Form X) — the generation offsets the transmission capacity the load needs — while PCLR (Form W) is the natural election for generation-light, flexibility-rich loads. Projects with both attributes should model both before signing either; both forms bind. And whichever ERCOT pathway you elect, the PUCT-side classification of your generation proceeds on its own logic — electing WLPUN does not answer the Part A/Part B question, and vice versa.

One team should own the whole map

The recurring failure mode we see is fragmentation: the market/regulatory group files the GCR, the development team handles ERCOT forms, and nobody reconciles them until a discrepancy surfaces in a review. A single compliance register — every filing, every classification position, every date — is cheap insurance.

Frequently Asked Questions

How Keentel Engineering Can Help

Keentel Engineering works both sides of this map for large load and BYOG projects: PGC-versus-self-generator classification support and GCR filing preparation with defensible capacity ratings; ERCOT resource registration (RARF) built consistent with your PUCT filings; WLPUN and PCLR election analysis including locational curtailment-risk studies; Form W/Form X preparation support; and the single compliance register that keeps every filing telling the same story. One engineering team, one set of project facts, every regulator satisfied.