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Mills County, Texas: solar, wind, and storage projects and permits

Queue data as of ERCOT's September 2026 GIS report · Contacts checked 2026-09-26 · Next update early next month

7 proposed energy projects from ERCOT's September 2026 report, plus who to call in Mills County and in TCEQ Region 9 before signing a solar, wind, or battery storage lease.

Check land in Mills CountyOpens the land report with the map on the county; click a spot for its flood, wetland, habitat, line-distance and parcel check.

Power reliability here: minutes without power per year, outages per year, and outage length for Mills County, 2013–2024, from the serving utilities' EIA filings.

What energy projects are proposed in Mills County?

ERCOT's September 2026 interconnection report lists 7 proposed energy projects in Mills County (2 solar, 1 wind and 4 battery storage), about 1,410 MW in all. 3 of the 7 have a signed interconnection agreement, and 1 has been approved for energization or synchronization.

What stands out in Mills County

By capacity, battery storage leads in Mills County with 776 MW across 4 projects, followed by solar (2 projects, 332 MW) and wind (1 project, 302 MW). The largest single project is Priddy Wind, a 302 MW wind project listed under ENGIE North America, approved for synchronization, and its target online date is Dec 2026. Of the 7, 4 are still in ERCOT's study process, 2 have a signed interconnection agreement but no security posted yet and 1 is approved for energization or synchronization. Connection points are mostly at 345 kV (3 projects) and 138 kV (3 projects) (why the voltage matters). Mills Tx Solar LLC is listed on the most projects here (2 of 7); 6 different companies appear in all. Target online dates for the projects not yet running span Aug 2028 to May 2030. All of them fall in ERCOT's North load zone.

A listing is a request to study a grid connection, not a built project; the stage column says how far each one has gone.

Stage, most advanced first: Approved for synchronization (first power) · Approved for energization (backfeed) · Under construction · Signed; security posted (interconnection agreement signed and financial security posted) · Signed (agreement signed, security not yet posted) · In study (screening or full interconnection study, no agreement). A target date that has already passed is marked; ERCOT keeps the developer's last reported date until the developer changes it.

Scroll the table sideways to see every column.

Crowded connection points in Mills County

Substations and switching stations named by two or more of the county's requests, matched on ERCOT's PSS/E bus number rather than the exact wording, so "60404 SOLSTICE", "AEP Solstice Substation #60404" and a tap off the Solstice line count together. Every request statewide that names the bus is listed; a request on a tap line counts toward both ends. Sharing a bus is not the same as sharing a study group, and ERCOT decides the latter.

What the stages and dates mean: how to read ERCOT's report. ERCOT's report lists self-limiting facilities (batteries that limit injection below nameplate) at 0 MW; repowers of existing plants show 0 with no capacity change. "Approved for energization" and "approved for synchronization" are ERCOT's own milestones (backfeed, then first power). "Shared with N other requests" counts active requests anywhere in ERCOT naming the same point of interconnection, matched on ERCOT's exact wording, so a bus written two ways counts as two points. Source: ERCOT Generator Interconnection Status (GIS) Report, September 2026, planning data entered by developers and transmission providers that ERCOT says may contain errors. Parcel & Grid is not affiliated with ERCOT.

Who to contact in Mills County

• Mills County appraisal district and tax office: parcel records and agricultural valuation, which a lease can end (directory, Texas Comptroller · rollback taxes).
• TCEQ Region 9, Waco: 6801 Sanger Ave, Ste 2500, Waco TX 76710-7826, 254-751-0335; spills, 24 hours: 800-832-8224. Handles the construction stormwater permit for sites of 1 acre or more (TCEQ).
• Mills County judge and commissioners court: road use agreements, tax agreements, and floodplain development permits where the county takes part in the flood insurance program.
• Flood maps: FEMA map search for Mills County.

Permits and reviews for Mills County

Texas has no state siting permit for solar or wind, and Texas counties generally have no zoning authority, so a project in Mills County is shaped by site control, the county road use agreement, tax agreements, and the grid connection (what still applies · the twelve approvals, stage by stage). Wetland, endangered species, historic, and FAA reviews depend on the site: statewide and federal contacts · decommissioning law.

How a project in Mills County connects to the grid

Mills County is on the ERCOT grid. The projects listed above are in ERCOT's North load zone. The serving utility handles the connection request. Interconnection by market and utility · what ERCOT is.

How long it takes. ERCOT staff put the connection process at 18 to 30 months for generation of 10 MW or more, before construction or supply delays (ERCOT, Oct. 2024). Across the U.S., the median project built in 2025 took 61 months from interconnection request to commercial operation (Berkeley Lab, Queued Up 2026), so a lease signed today usually means construction years out: timelines by market.

Solar for homes and businesses in Mills County

Texas rules for rooftop and on-site systems are the same in every county; your electric utility sets the application steps: Texas home and business solar rules · your utility's application links.

Other counties served by TCEQ Region 9

Bell · Bosque · Brazos · Burleson · Coryell · Falls · Freestone · Grimes · Hamilton · Hill · Lampasas · Leon · Limestone · Madison · McLennan · Milam · Robertson · San Saba · Washington