Crowned Heron 1 and Cartwheel 1 are expected to be completed in the summer of 2025, whereas Crowned Heron 2 will enter its commissioning phase in the fall of 2025.

RWE said the projects will provide stability to the Electric Reliability Council of Texas (ERCOT) grid.

Hanson Wood, head of development, utility-scale renewables for RWE Clean Energy, said the projects mark a “significant step” in RWE’s commitment to bolstering energy infrastructure in ERCOT.

“When completed and operating, our Crowned Heron 1 and 2 and Cartwheel battery projects will serve as reliable energy storage solutions to enhance grid stability and support the state’s rapidly growing renewables sector,” Wood added.

RWE continues to expand its presence in the US market and, earlier this year (May), secured 599MW of solar and storage projects in the states of New York, Idaho, and Oregon.

The largest of the sites is the 300MWac Cedar Ridge solar PV project in Blaine County, Idaho, co-located with a 150MW/600MWh four-hour duration BESS. This asset is located within the PacifiCorp region and will “provide regional grid support consistent with PacifiCorp’s resource planning forecasts”, RWE said.

In February, RWE completed construction of three BESS projects in Texas and Arizona, representing 190MW/360MWh. All three are co-located with solar PV projects.

Bright Arrow is a 100MW/200MWh BESS and 300MWac PV project in Sulphur Springs, while Big Star is an 80MW/120MWh system paired with a 200MW PV project in Bastrop County, both in Texas. In Arizona, it has brought online the 10/40MWh BESS, 52.5MWac PV Mesquite 4 project.

ERCOT installs 1,200MWh of BESS in Q2 2024

The ERCOT market continues to see large-scale BESS projects developed, with Modo Energy telling Energy-Storage.news that it had reached 5GW of large-scale BESS online by early summer this year.

ERCOT installed 20% of all grid-scale capacity in the US in Q2 2024, totalling 1,200MWh, according to the newest edition of Wood Mackenzie’s US quarterly US Energy Storage Monitor report.

When factoring in Arizona (2,600MWh) and California (4,492MWh), the three states account for 85% of grid-scale deployments in terms of capacity in Q2 2024. It is worth noting that Texas BESS projects are often co-located with solar PV and have a duration of 1-hour and 2-hours.

Last month, Energy-Storage.News Premium reported that ERCOT approved an additional 480MW of BESS capacity for commercial operations in August. Three new storage projects were connected to the grid in the first half of August and were available for dispatch by ERCOT on August 20. During that day, the Texas grid operator exceeded its peak demand record without needing to implement conservation measures.