# Bellefield Solar and Energy Storage Farm

CAISO Batteries, Solar Photovoltaic · https://askthegrid.com/assets/facilities/bellefield-solar-and-energy-storage-farm

Bellefield Solar and Energy Storage Farm is a hybrid solar and battery storage facility with 1,000 MW of EIA-reported total operating capacity and 4,000 MWh of reported storage energy capacity in Kern County, California, registered as EIA Plant ID 64210. The AES Corporation is the current owner; 50LW 8me LLC is the registered plant entity or operator. In June 2023, AES and Avantus described Bellefield as the largest permitted solar-plus-storage project in the United States.

## Key facts

- Technology: Batteries, Solar Photovoltaic
- Power capacity: 1000 MW
- Operating status: operating

## Grid and market context

- ISO/RTO: CAISO
- Balancing authority: CISO (CAISO)
- Substation: Southern California Edison (SCE) Windhub Substation
- Point of interconnection: Southern California Edison (SCE) Windhub Substation
- Transmission owner: Southern California Edison (SCE)
- Interconnection voltage: 230 kV

## Source-backed facts

- Owner logo domain: aes.com — AES | Accelerating the Future of Global Energy · confidence: high
- Owner name: The AES Corporation — AES Completes First Phase of Largest Solar-Plus-Storage Project in the United States · confidence: medium
- Description: Bellefield Solar and Energy Storage Farm is a hybrid solar-and-battery facility in Kern County, California, identified as EIA plant 64210. Public plant data report 1,000 MW across two generating units; AES describes the Bellefield project as two phases, each with 500 MW of solar and 500 MW of four-hour battery storage. AES says it will serve as the long-term owner and operator, with a transmission line connecting the project to Southern California Edison’s Windhub Substation. — Bellefield Solar + Storage | AES · confidence: medium
- Parties: [{"relationship":"Long-term owner and operator","name":"The AES Corporation","official_url":"https://www.aes.com/"},{"relationship":"EIA-registered plant entity/operator","name":"50LW 8me LLC","official_url":null},{"relationship":"Original project developer","name":"Avantus","official_url":"https://avantus.com/"},{"relationship":"Phase-one PPA offtaker","name":"Amazon","official_url":"https://www.aboutamazon.com/about-us"},{"relationship":"Transmission and interconnection utility","name":"Southern California Edison","official_url":"https://www.sce.com/"}] — Bellefield Solar + Storage | AES · confidence: medium
- Parties: [{"relationship":"Long-term owner and operator","name":"The AES Corporation","official_url":"https://www.aes.com/"},{"relationship":"EIA-registered plant entity/operator","name":"50LW 8me LLC","official_url":null},{"relationship":"Original project developer","name":"Avantus","official_url":"https://avantus.com/"},{"relationship":"Phase-one PPA offtaker","name":"Amazon","official_url":"https://www.aboutamazon.com/about-us"},{"relationship":"Transmission and interconnection utility","name":"Southern California Edison","official_url":"https://www.sce.com/"}] — Avantus Completes Sale of Nation’s Largest Permitted Solar and Integrated Storage Project to AES | Avantus · confidence: medium
- Parties: [{"relationship":"Long-term owner and operator","name":"The AES Corporation","official_url":"https://www.aes.com/"},{"relationship":"EIA-registered plant entity/operator","name":"50LW 8me LLC","official_url":null},{"relationship":"Original project developer","name":"Avantus","official_url":"https://avantus.com/"},{"relationship":"Phase-one PPA offtaker","name":"Amazon","official_url":"https://www.aboutamazon.com/about-us"},{"relationship":"Transmission and interconnection utility","name":"Southern California Edison","official_url":"https://www.sce.com/"}] — AES Completes First Phase of Largest Solar-Plus-Storage Project in the United States · confidence: medium
- Parties.0: {"relationship":"Long-term owner and operator","name":"The AES Corporation","official_url":"https://www.aes.com/"} — Bellefield Solar + Storage | AES · confidence: medium
- Parties.0: {"relationship":"Long-term owner and operator","name":"The AES Corporation","official_url":"https://www.aes.com/"} — AES Completes First Phase of Largest Solar-Plus-Storage Project in the United States · confidence: medium
- Parties.2: {"relationship":"Original project developer","name":"Avantus","official_url":"https://avantus.com/"} — Avantus Completes Sale of Nation’s Largest Permitted Solar and Integrated Storage Project to AES | Avantus · confidence: medium
- Parties.3: {"relationship":"Phase-one PPA offtaker","name":"Amazon","official_url":"https://www.aboutamazon.com/about-us"} — AES Completes First Phase of Largest Solar-Plus-Storage Project in the United States · confidence: high
- Parties.4: {"relationship":"Transmission and interconnection utility","name":"Southern California Edison","official_url":"https://www.sce.com/"} — Bellefield Solar + Storage | AES · confidence: high
- Unit configuration: Hybrid solar photovoltaic and battery energy storage facility; two phases, each with 500 MW of solar and 500 MW of four-hour battery storage — Source · confidence: medium
- Duration hours: 4 — Source · confidence: high
- Energy mwh: 4000 — Source · confidence: medium
- Construction scope: The exact EIA plant record reports 2 operational generating units totaling 1,000 MW. AES describes Bellefield as a two-phase hybrid project, with each phase comprising 500 MW of solar and 500 MW of four-hour battery storage. Documented physical works include a 14-mile transmission line to SCE’s Windhub Substation; 230 kV overhead and underground transmission lines; substations and switchyards; collection and communication systems; service roads; energy-storage facilities; O&M facilities; and three permanent property entrances. Clark Bros. reports civil/site-development work including clearing, grading, laydown yards, substation and BESS preparation, SWPPP and dust control, and roadway construction. No source provides installed counts for solar modules, inverters, battery units, or storage containers. — Bellefield Solar + Storage | AES · confidence: medium
- Construction scope: The exact EIA plant record reports 2 operational generating units totaling 1,000 MW. AES describes Bellefield as a two-phase hybrid project, with each phase comprising 500 MW of solar and 500 MW of four-hour battery storage. Documented physical works include a 14-mile transmission line to SCE’s Windhub Substation; 230 kV overhead and underground transmission lines; substations and switchyards; collection and communication systems; service roads; energy-storage facilities; O&M facilities; and three permanent property entrances. Clark Bros. reports civil/site-development work including clearing, grading, laydown yards, substation and BESS preparation, SWPPP and dust control, and roadway construction. No source provides installed counts for solar modules, inverters, battery units, or storage containers. — AES Completes First Phase of Largest Solar-Plus-Storage Project in the United States · confidence: medium
- Construction scope: The exact EIA plant record reports 2 operational generating units totaling 1,000 MW. AES describes Bellefield as a two-phase hybrid project, with each phase comprising 500 MW of solar and 500 MW of four-hour battery storage. Documented physical works include a 14-mile transmission line to SCE’s Windhub Substation; 230 kV overhead and underground transmission lines; substations and switchyards; collection and communication systems; service roads; energy-storage facilities; O&M facilities; and three permanent property entrances. Clark Bros. reports civil/site-development work including clearing, grading, laydown yards, substation and BESS preparation, SWPPP and dust control, and roadway construction. No source provides installed counts for solar modules, inverters, battery units, or storage containers. — Source · confidence: medium
- Construction scope: The exact EIA plant record reports 2 operational generating units totaling 1,000 MW. AES describes Bellefield as a two-phase hybrid project, with each phase comprising 500 MW of solar and 500 MW of four-hour battery storage. Documented physical works include a 14-mile transmission line to SCE’s Windhub Substation; 230 kV overhead and underground transmission lines; substations and switchyards; collection and communication systems; service roads; energy-storage facilities; O&M facilities; and three permanent property entrances. Clark Bros. reports civil/site-development work including clearing, grading, laydown yards, substation and BESS preparation, SWPPP and dust control, and roadway construction. No source provides installed counts for solar modules, inverters, battery units, or storage containers. — Bellefield Solar + Storage - AES Corporation · confidence: medium
- Kind: solar — Bellefield Solar + Storage - AES Corporation · confidence: medium
- Description: Bellefield Solar and Energy Storage Farm, EIA plant 64210, is a hybrid solar photovoltaic and battery project in Kern County, California, within CAISO. AES describes the project as two phases, each comprising 500 MW of solar and 500 MW of four-hour battery storage, with a 14-mile transmission line to Southern California Edison’s Windhub Substation. Avantus, formerly 8minute, developed and sold the project to AES in June 2023; phase one is supported by a 15-year power purchase agreement with Amazon. AES completed construction of the 1,000 MW Bellefield 1 phase in June 2025, while construction of Bellefield 2 was scheduled for completion in 2026. — Bellefield Solar + Storage | AES · confidence: medium
- Description: Bellefield Solar and Energy Storage Farm, EIA plant 64210, is a hybrid solar photovoltaic and battery project in Kern County, California, within CAISO. AES describes the project as two phases, each comprising 500 MW of solar and 500 MW of four-hour battery storage, with a 14-mile transmission line to Southern California Edison’s Windhub Substation. Avantus, formerly 8minute, developed and sold the project to AES in June 2023; phase one is supported by a 15-year power purchase agreement with Amazon. AES completed construction of the 1,000 MW Bellefield 1 phase in June 2025, while construction of Bellefield 2 was scheduled for completion in 2026. — AES Acquires Largest Permitted Solar-Plus-Storage Project in the United States · confidence: medium
- Description: Bellefield Solar and Energy Storage Farm, EIA plant 64210, is a hybrid solar photovoltaic and battery project in Kern County, California, within CAISO. AES describes the project as two phases, each comprising 500 MW of solar and 500 MW of four-hour battery storage, with a 14-mile transmission line to Southern California Edison’s Windhub Substation. Avantus, formerly 8minute, developed and sold the project to AES in June 2023; phase one is supported by a 15-year power purchase agreement with Amazon. AES completed construction of the 1,000 MW Bellefield 1 phase in June 2025, while construction of Bellefield 2 was scheduled for completion in 2026. — AES Completes First Phase of Largest Solar-Plus-Storage Project in the United States · confidence: medium
- Quality notes: ["The exact EIA identity is plant 64210, generator 50LWA, registered to 50LW 8me LLC in Kern County; AES separately describes the broader two-phase development as a 2,000 MW project.","The 1,000 MW directory capacity corresponds to the completed or near-completed Bellefield 1 phase; the ultimate project configuration is 2,000 MW across two phases.","The disclosed battery configuration is four-hour duration. AES reported phase-one construction completion in June 2025 and expected in-service timing in the second half of 2025; its later annual report recorded substantial completion in December 2025. No exact commercial-operation day is stated."] — AES Completes First Phase of Largest Solar-Plus-Storage Project in the United States · confidence: medium
- Commercial parties: [{"relationship":"Long-term owner and operator","name":"The AES Corporation","detail":"AES acquired the Bellefield project in June 2023 and states that it will serve as the long-term owner and operator.","official_url":"https://www.aes.com/"},{"relationship":"EIA-registered plant entity/operator","name":"50LW 8me LLC","detail":"The entity associated with EIA plant 64210 and generator 50LWA in the EIA/FERC plant record.","official_url":null},{"relationship":"Original project developer and seller","name":"Avantus","detail":"Avantus, formerly 8minute, developed the two phases and announced the sale of Bellefield to AES on June 7, 2023.","official_url":"https://avantus.com/"},{"relationship":"Phase-one offtaker","name":"Amazon","detail":"Phase one is supported by a 15-year power purchase agreement with an Amazon corporate customer.","official_url":"https://www.aboutamazon.com/about-us"},{"relationship":"Transmission and interconnection utility","name":"Southern California Edison","detail":"A 14-mile transmission line connects the project to SCE’s Windhub Substation.","official_url":"https://www.sce.com/"},{"relationship":"Preferred investment partner","name":"Hannon Armstrong Sustainable Infrastructure Capital","detail":"Hannon Armstrong, commonly known as HASI, invested $250 million in Bellefield for a preferred membership interest in November 2024.","official_url":"https://www.hasi.com/"}] — Bellefield Solar + Storage | AES · confidence: medium
- Commercial parties: [{"relationship":"Long-term owner and operator","name":"The AES Corporation","detail":"AES acquired the Bellefield project in June 2023 and states that it will serve as the long-term owner and operator.","official_url":"https://www.aes.com/"},{"relationship":"EIA-registered plant entity/operator","name":"50LW 8me LLC","detail":"The entity associated with EIA plant 64210 and generator 50LWA in the EIA/FERC plant record.","official_url":null},{"relationship":"Original project developer and seller","name":"Avantus","detail":"Avantus, formerly 8minute, developed the two phases and announced the sale of Bellefield to AES on June 7, 2023.","official_url":"https://avantus.com/"},{"relationship":"Phase-one offtaker","name":"Amazon","detail":"Phase one is supported by a 15-year power purchase agreement with an Amazon corporate customer.","official_url":"https://www.aboutamazon.com/about-us"},{"relationship":"Transmission and interconnection utility","name":"Southern California Edison","detail":"A 14-mile transmission line connects the project to SCE’s Windhub Substation.","official_url":"https://www.sce.com/"},{"relationship":"Preferred investment partner","name":"Hannon Armstrong Sustainable Infrastructure Capital","detail":"Hannon Armstrong, commonly known as HASI, invested $250 million in Bellefield for a preferred membership interest in November 2024.","official_url":"https://www.hasi.com/"}] — Avantus Completes Sale of Nation’s Largest Permitted Solar and Integrated Storage Project to AES | Avantus · confidence: medium
- Commercial parties: [{"relationship":"Long-term owner and operator","name":"The AES Corporation","detail":"AES acquired the Bellefield project in June 2023 and states that it will serve as the long-term owner and operator.","official_url":"https://www.aes.com/"},{"relationship":"EIA-registered plant entity/operator","name":"50LW 8me LLC","detail":"The entity associated with EIA plant 64210 and generator 50LWA in the EIA/FERC plant record.","official_url":null},{"relationship":"Original project developer and seller","name":"Avantus","detail":"Avantus, formerly 8minute, developed the two phases and announced the sale of Bellefield to AES on June 7, 2023.","official_url":"https://avantus.com/"},{"relationship":"Phase-one offtaker","name":"Amazon","detail":"Phase one is supported by a 15-year power purchase agreement with an Amazon corporate customer.","official_url":"https://www.aboutamazon.com/about-us"},{"relationship":"Transmission and interconnection utility","name":"Southern California Edison","detail":"A 14-mile transmission line connects the project to SCE’s Windhub Substation.","official_url":"https://www.sce.com/"},{"relationship":"Preferred investment partner","name":"Hannon Armstrong Sustainable Infrastructure Capital","detail":"Hannon Armstrong, commonly known as HASI, invested $250 million in Bellefield for a preferred membership interest in November 2024.","official_url":"https://www.hasi.com/"}] — AES Acquires Largest Permitted Solar-Plus-Storage Project in the United States · confidence: medium
- Quality notes.1: The 1,000 MW directory capacity corresponds to the completed or near-completed Bellefield 1 phase; the ultimate project configuration is 2,000 MW across two phases. — AES Completes First Phase of Largest Solar-Plus-Storage Project in the United States · confidence: high
- Timeline.0: {"event":"Acquisition and sale","date":"2023-06-07","detail":"AES announced its acquisition of the 2 GW Bellefield project from Avantus. The project was in late-stage development, with two 500 MW solar phases and up to 500 MW of four-hour battery storage per phase."} — AES Acquires Largest Permitted Solar-Plus-Storage Project in the United States · confidence: high
- Timeline.0: {"event":"Acquisition and sale","date":"2023-06-07","detail":"AES announced its acquisition of the 2 GW Bellefield project from Avantus. The project was in late-stage development, with two 500 MW solar phases and up to 500 MW of four-hour battery storage per phase."} — Avantus Completes Sale of Nation’s Largest Permitted Solar and Integrated Storage Project to AES | Avantus · confidence: high
- Timeline.1: {"event":"Construction start","date":"2023","detail":"Project reporting places construction of Bellefield 1 in the third quarter of 2023."} — AES Completes Bellefield Phase One, Energising Record... · confidence: medium
- Timeline.5: {"event":"Financial close","date":"2025-01-06","detail":"AES reached financial close on a reported $1.68 billion Bellefield financing package consisting of construction-to-term debt, a tax-equity bridge loan, and a letter-of-credit facility."} — AES closes Project Bellefield solar-plus-storage financing - Proximo · confidence: medium
- Commercial parties.0: {"relationship":"Long-term owner and operator","name":"The AES Corporation","detail":"AES acquired the Bellefield project in June 2023 and states that it will serve as the long-term owner and operator.","official_url":"https://www.aes.com/"} — Bellefield Solar + Storage | AES · confidence: high
- Commercial parties.2: {"relationship":"Original project developer and seller","name":"Avantus","detail":"Avantus, formerly 8minute, developed the two phases and announced the sale of Bellefield to AES on June 7, 2023.","official_url":"https://avantus.com/"} — Avantus Completes Sale of Nation’s Largest Permitted Solar and Integrated Storage Project to AES | Avantus · confidence: high
- Commercial parties.3: {"relationship":"Phase-one offtaker","name":"Amazon","detail":"Phase one is supported by a 15-year power purchase agreement with an Amazon corporate customer.","official_url":"https://www.aboutamazon.com/about-us"} — AES Acquires Largest Permitted Solar-Plus-Storage Project in the United States · confidence: high
- Commercial parties.3: {"relationship":"Phase-one offtaker","name":"Amazon","detail":"Phase one is supported by a 15-year power purchase agreement with an Amazon corporate customer.","official_url":"https://www.aboutamazon.com/about-us"} — AES Completes First Phase of Largest Solar-Plus-Storage Project in the United States · confidence: high
- Commercial parties.4: {"relationship":"Transmission and interconnection utility","name":"Southern California Edison","detail":"A 14-mile transmission line connects the project to SCE’s Windhub Substation.","official_url":"https://www.sce.com/"} — Bellefield Solar + Storage | AES · confidence: high
- Seller: Avantus — AES Acquires Largest Permitted Solar-Plus-Storage Project in the United States · confidence: medium
- Prior owner: Avantus — AES Acquires Largest Permitted Solar-Plus-Storage Project in the United States · confidence: medium
- Substation: Southern California Edison (SCE) Windhub Substation — Bellefield Solar Project by 50LW 8ME LLC (8Minute Energy) · confidence: medium

## Timeline

- 2023-06-07 — Acquisition and sale
  AES announced its acquisition of the 2 GW Bellefield project from Avantus. The project was in late-stage development, with two 500 MW solar phases and up to 500 MW of four-hour battery storage per phase.
  Source: AES Acquires Largest Permitted Solar-Plus-Storage Project in the United States (https://www.prnewswire.com/news-releases/aes-acquires-largest-permitted-solar-plus-storage-project-in-the-united-states-301844765.html)
- 2025-06-11 — Phase-one construction completion
  AES announced completion of construction of the 1,000 MW Bellefield 1 phase. The phase-one project is under a 15-year contract with Amazon, and Bellefield 2 was on track for completion in 2026.
  Source: AES Completes First Phase of Largest Solar-Plus-Storage Project in the United States (https://www.prnewswire.com/news-releases/aes-completes-first-phase-of-largest-solar-plus-storage-project-in-the-united-states-302478336.html)
- 2026 — Phase-two expected completion
  AES reported that construction of Bellefield 2 was expected to be completed in 2026.
  Source: AES Completes First Phase of Largest Solar-Plus-Storage Project in the United States (https://www.prnewswire.com/news-releases/aes-completes-first-phase-of-largest-solar-plus-storage-project-in-the-united-states-302478336.html)

## Sources

- [AES | Accelerating the Future of Global Energy](https://www.aes.com/) — aes.com · tier other
- [Lookup Data - MBR](https://mbrweb.ferc.gov/LookupData/Index/entities_to_genassets?page=389) — mbrweb.ferc.gov · tier regulatory
- [Bellefield Solar + Storage | AES](https://www.aes.com/sustainability-impact/people-communities/projects/bellefield-solar-storage) — aes.com · tier other
- [AES Completes First Phase of Largest Solar-Plus-Storage Project in the United States](https://www.prnewswire.com/news-releases/aes-completes-first-phase-of-largest-solar-plus-storage-project-in-the-united-states-302478336.html) — prnewswire.com · tier other
- [Avantus Completes Sale of Nation’s Largest Permitted Solar and Integrated Storage Project to AES | Avantus](https://avantus.com/news/avantus-completes-sale-of-nations-largest-permitted-solar-and-integrated-storage-project-to-aes) — avantus.com · tier other
- [Source](https://aes.com/sustainability-impact/people-communities/projects/bellefield-solar-storage) — aes.com · tier other
- [Source](https://downloads.regulations.gov/FWS-R8-ES-2022-0034-0004/content.pdf) — downloads.regulations.gov · tier regulatory
- [Bellefield Solar + Storage, California, US - NS Energy](https://www.nsenergybusiness.com/projects/bellefield-solar-storage-california-us/) — nsenergybusiness.com · tier other
- [AES Acquires Largest Permitted Solar-Plus-Storage Project in the United States](https://www.prnewswire.com/news-releases/aes-acquires-largest-permitted-solar-plus-storage-project-in-the-united-states-301844765.html) — prnewswire.com · tier other
- [Source](https://www.aes.com/sites/vault/files/2026-03/AES-Corp-2025-Annual-Report-03-20-2026.pdf) — aes.com · tier other
- [AES closes Project Bellefield solar-plus-storage financing - Proximo](https://www.proximoinfra.com/news/68054/aes-closes-project-bellefield-solar-plus-storage-financing) — proximoinfra.com · tier other
- [AES Completes Bellefield Phase One, Energising Record ...](https://list.solar/news/aes-completes/) — list.solar · tier other
- [aes-20250331](https://www.sec.gov/Archives/edgar/data/874761/000087476125000035/aes-20250331.htm) — sec.gov · tier regulatory
- [Bellefield Solar Project by 50LW 8ME LLC (8Minute Energy)](https://ceqanet.lci.ca.gov/2021010168/3) — ceqanet.lci.ca.gov · tier regulatory

## Data quality

- The exact EIA identity is plant 64210, generator 50LWA, registered to 50LW 8me LLC in Kern County; AES separately describes the broader two-phase development as a 2,000 MW project. The 1,000 MW directory capacity corresponds to the completed or near-completed Bellefield 1 phase; the ultimate project configuration is 2,000 MW across two phases. The disclosed battery configuration is four-hour duration. No exact commercial-operation day is stated.

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Source: Ask the Grid — https://askthegrid.com/