Waller 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
5 proposed energy projects from ERCOT's September 2026 report, plus who to call in Waller County and in TCEQ Region 12 before signing a solar, wind, or battery storage lease.
Check land in Waller 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 Waller County, 2013–2024, from the serving utilities' EIA filings.
What energy projects are proposed in Waller County?
ERCOT's September 2026 interconnection report lists 5 proposed energy projects in Waller County (1 solar and 4 battery storage), about 924 MW in all. 3 of the 5 have a signed interconnection agreement.
What stands out in Waller County
By capacity, battery storage leads in Waller County with 566 MW across 4 projects, followed by solar (1 project, 358 MW). The largest single project is Twinwood Solar 1, a 358 MW solar project listed under Twinwood PV1, LLC, with its agreement signed and security posted, and its target online date is Feb 2029. Of the 5, 2 are still in ERCOT's study process and 3 have posted security or started construction. Connection points are mostly at 138 kV (4 projects) and 69 kV (1 project) (why the voltage matters). Each of the 5 projects is listed under a different company. Target online dates for the projects not yet running span Feb 2027 to Feb 2029. All of them fall in ERCOT's Houston 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.
| Project and connection point | Developer as listed by ERCOT | Type | MW | Target online date iThe commercial operation date the developer reported to ERCOT (ERCOT calls it the projected COD). Developers set and change it, many projects slip, and some are never built. It is not a promise or a construction date. | Stage |
|---|---|---|---|---|---|
| Seaway BESSTSP Substation Name - Seaway | Mount Whitney Energy Storage LLC | Battery storage (stand-alone) | 9.9 | Feb 2027 | Signed; security posted |
| Maderagemela BESS1Tap 138kV 44750 FULSHR_S25_8 to 44860 TWINWD_S25_8 | Twinwood ES1, LLC | Battery storage (stand-alone) | 154.0 | Feb 2029 | Signed; security posted |
| Twinwood Solar 1Tap 138kV 44750 FULSHR_S25_8 - 44860 TWINWD_S25_8 | Twinwood PV1, LLC | Solar | 358.1 | Feb 2029 | Signed; security posted |
| Caladium BESS57664 Sunnyside 69kV | Caladium Storage, LLC | Battery storage (stand-alone) | 201.3 | Nov 2027 | In study |
| Augie BESS46560 Waller 138kV | BRP Blue Topaz 5, LLC | Battery storage (stand-alone) | 200.8 | Dec 2027 | In study |
Crowded connection points in Waller 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.
FULSHR_S25_8 (44750) 138 kV 2 requests · 512 MW2 signed; security posted
- Twinwood Solar 1 26INR0425 · Solar · 358 MW · Signed; security posted
- Maderagemela BESS1 26INR0426 · Battery storage · 154 MW · Signed; security posted
TWINWD_S25_8 (44860) 138 kV 2 requests · 512 MW2 signed; security posted
- Twinwood Solar 1 26INR0425 · Solar · 358 MW · Signed; security posted
- Maderagemela BESS1 26INR0426 · Battery storage · 154 MW · Signed; security posted
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 Waller County
- Waller County appraisal district and tax office: parcel records and agricultural valuation, which a lease can end (directory, Texas Comptroller · rollback taxes).
- TCEQ Region 12, Houston: 5425 Polk St, Ste H, Houston TX 77023-1452, 713-767-3500; spills, 24 hours: 800-832-8224. Handles the construction stormwater permit for sites of 1 acre or more (TCEQ).
- Waller 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 Waller County.
Permits and reviews for Waller County
Texas has no state siting permit for solar or wind, and Texas counties generally have no zoning authority, so a project in Waller 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 Waller County connects to the grid
Waller County is on the ERCOT grid. The projects listed above are in ERCOT's Houston 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 Waller 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.
Get the land report for a spot in Waller County
Get a free land report for any point: flood zone, wetlands, nearest power line, soils, and parcel acreage.
Other counties served by TCEQ Region 12
Austin · Brazoria · Chambers · Colorado · Fort Bend · Galveston · Harris · Liberty · Matagorda · Montgomery · Walker · Wharton