US renewable energy IPP Longroad Energy’s Sun Pond solar-plus-storage project in Maricopa County, Arizona, US has reached commercial operation.
Announced 5 May, Sun Pond combines 111MW of solar PV generation with a 85MW/340MWh battery energy storage system (BESS), and has long-term power purchase agreements (PPAs) with California community choice aggregators (CCA) Ava Community Energy and San José Clean Energy (SJCE).
In December 2024, Longroad announced financial close of Sun Pond, noting that construction company McCarthy Building Companies would act as the engineering, procurement and construction (EPC) contractor on the project.
Additionally, the BESS cells would be provided by Japan-headquartered lithium-ion battery manufacturer Automotive Energy Supply Corporation (AESC), which is majority owne by Chinese firm Envision Energy.
Try Premium for just $1
- Full premium access for the first month at only $1
- Converts to an annual rate after 30 days unless cancelled
- Cancel anytime during the trial period
Premium Benefits
- Expert industry analysis and interviews
- Digital access to PV Tech Power journal
- Exclusive event discounts
Or get the full Premium subscription right away
Or continue reading this article for free
BESS integrator Fluence, which at that time, had recently secured US-manufactured cells from AESC, would work with Longroad and operations and maintenance firm NovaSource Power Services to provide operations and maintenance (O&M) services for the Sun Pond project.
In the past week, AESC sold its stake in the US lithium-ion battery manufacturing business to US firm Fixx Energy, amid tighter restrictions in the US on companies seen to be controlled by the Chinese government.
Longroad has specified that Fluence’s Gridstack BESS solution was used at Sun Pond. PV modules from First Solar, smart trackers from Nextpower, and solar inverters from Sungrow were also used in the project.
Sun Pond is part of Longroad’s Sun Streams Complex, which is made up of three additional projects, and brings the Complex’s total capacity to 973MW solar PV and 600MW/2,400MWh BESS.
| Sun Streams Complex Project | MW PV, MW/MWh BESS |
| Sun Streams 2 | 200MW solar PV |
| Sun Streams 3 | 285MW solar PV, 215MW/860MWh BESS |
| Sun Streams 4 | 377MW solar PV, 300MW/1200MWh BESS |
| Sun Pond | 111MW solar PV, 85MW/340MWh BESS |
Longroad claims that the Sun Streams Complex will provide over US$300 million in benefits to Arizona schools and local communities through its long-term leases with the Arizona State Land Department and tax remittances.
In March 2024, the company closed on Serrano, a large-scale solar PV and battery storage project in Pinal and Pima Counties, Arizona, with PV modules also developed by First Solar.
Prior to closing on the Serrano project, Longroad closed on Sun Streams 4, which was the company’s largest solar and storage project to date, at 377MW PV and 300MW/1,200MWh. The project was part of a portfolio it acquired from First Solar.
