Hybrid Power

RWE Boosts Battery Storage with Three New Projects

German energy giant RWE has added three large battery energy storage (BESS) projects to the company’s U.S. portfolio. The group on Feb. 14 announced the completion of two installations in Texas and one in Arizona, and said energy storage systems now comprise more than one-third of the company’s U.S. renewable energy and storage development pipeline.

RWE said the latest additions as part of its “Growing Green Strategy” are the Bright Arrow and Big Star projects in Texas, and Mesquite 4 in Arizona. The company said its global battery energy storage capacity now totals about 700 MW, with more than 1 GW of such projects under construction.

“Battery storage is growing even more critical to enable the rapid deployment of wind and solar projects, help stabilize the U.S. power grid and better ensure that enough electric supply is available to meet demand,” said Andrew Flanagan, CEO of RWE Clean Energy. “As part of our Growing Green Strategy, we’re planning to increase our battery portfolio globally to 6 gigawatts by 2030, and these three new systems are contributing to that goal.”

Storage Paired with Solar Power

RWE has said its battery energy storage systems supply flexible electricity and are especially important during periods of peak demand for power. The three new systems are each paired with solar power at their sites, in keeping with the trend of pairing energy storage with renewable energy to address intermittency issues. The three new BESS store excess electricity from the solar arrays, with the ability to dispatch that energy to the grid as needed.

The new projects include:

Bright Arrow: This 100 MW (200 MWh) BESS, paired with 300-MWac of solar photovoltaic (PV) power, is located in Sulphur Springs, Texas. The project came online in December 2023, with an additional 200 MWac of solar scheduled to achieve commercial operation in spring 2024. The BESS will participate in the ERCOT market and the solar PV electricity output will be provided to an affiliate of NRG Energy.
Big Star: This project includes 80 MW (120 MWh) of battery storage and 200 MWac of solar PV. Big Star, located in Bastrop County, Texas, is completing testing and is scheduled to achieve commercial operation in March 2024. The BESS will participate in the ERCOT market and the solar PV electricity output will be provided to a third party.
Mesquite 4: This 10 MW (40 MWh) battery storage and 52.5 MWac solar project in Maricopa County, Arizona, is expected to come online later this month. The addition of Mesquite 4 brings the total operating capacity of the Mesquite Complex to about 530 MWac. The solar PV electricity output and BESS services will be provided to Modesto Irrigation District.

RWE on Wednesday said the company “has leveraged its in-house solid technical battery energy storage experience and project design, modeling and system integration capabilities to ensure the operation of safe, high-performing and reliable assets. Additionally, the company markets its energy storage assets through its proprietary dispatch and optimization algorithms to extract maximum market value from its battery and renewable asset portfolio.”

RWE’s Big Star project includes 80 MW (120 MWh) of battery storage and 200 MWac of solar PV. The installation in Bastrop County, Texas, is completing testing and is scheduled to achieve commercial operation in March 2024. The BESS will participate in the ERCOT market and the solar PV electricity output will be provided to a third party. Source: RWE

Expanding Storage Business

RWE, which develops, builds, and operates battery storage systems in the U.S., Europe, and Australia, plans to expand its battery energy storage business to 6 GW of capacity worldwide by 2030. The company last year connected its first utility-scale BESS in the U.S., a 137-MWac (548 MWh) installation collocated with a 150-MWac solar PV array at the Fifth Standard complex in Fresno County, California. The Fresno system is RWE’s largest operating installation to date.

RWE in March 2023 acquired UK solar and battery developers JBM Solar, adding an advanced battery project development pipeline of 2.3 GW to its portfolio. The company also is planning, building, and operating innovative combined solar and storage plants at its German opencast mining sites. RWE also recently won the bid for a long-duration battery storage system (50 MW/400 MWh) in Australia. The company also continues to develop the Canopy Offshore Wind Farm, a planned 1.6-GW installation off the coast of Humboldt County in Northern California.

—Darrell Proctor is a senior associate editor for POWER (@POWERmagazine).