Figure

ERCOT storage capacity by participation tier, and the tier it cannot count

ERCOT publishes a capacity for three tiers of Texas storage and none at all for the fourth, the behind-the-meter fleets that reach the wholesale market through someone else's registration.

Log-scale bar chart of ERCOT storage capacity by participation tier, with visibility falling as each tier moves behind the meter. Transmission-connected Energy Storage Resources hold 21,633 MW of installed discharge capacity and carry a mark for the 12,017 MW discharge set at 20:24 CT on July 22, 2026, which was the fleet's all-time record when set and was passed on August 18 and again on August 23, 2026. Distribution-connected DGR and DESR hold 596 MW of registered capacity. ADER-registered behind-the-meter aggregation holds 158.2 MW of qualified Energy capability across seven commercial aggregations, drawn against a 500 MW pilot ceiling. The fourth tier, unregistered behind-the-meter storage, has no bar at all: ERCOT's unregistered-DER taxonomy has no storage bucket, so no ERCOT quantity measures it.

This figure is from the ERCOT July 2026 heat-wave case study, a primary-source reconstruction of an all-time demand record crossed on a week without record heat, and what the public record does and does not show about it.

Cite this figure

Corey Balgeman, "ERCOT storage capacity by participation tier, and the tier it cannot count," Grid Flexibility, 2026. https://gridflexibility.fyi/case-studies/ercot-heat-wave-july-2026/figures/ercot-visibility-gap

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Last updated: 2026-08-24.