# Silver State South Storage CAISO Batteries · https://askthegrid.com/assets/facilities/silver-state-south-storage Silver State South Storage is a battery energy storage facility with 200 MW of EIA-reported operating capacity and 800 MWh of reported energy capacity in Clark County, Nevada, registered as EIA Plant ID 67734. Silver State South Storage, LLC is the registered plant entity or operator. The facility interconnects at Primm 220 kV Substation at 220 kV. Its grid role is four-hour lithium-ion battery energy-storage resource contracted for SCE mid-term reliability procurement. ## Key facts - Technology: Batteries - Power capacity: 200 MW - Energy capacity: 800 MWh - Operating status: operating ## Grid and market context - ISO/RTO: CAISO - Balancing authority: CISO (CAISO) - Substation: Primm 220 kV Substation - Point of interconnection: Primm 220 kV Substation - Transmission owner: Southern California Edison Company (SCE) - Interconnection voltage: 220 kV ## Source-backed facts - Identifiers: [{"value":"67734","system":"EIA plant ID"},{"value":"SSSB","system":"FERC/EIA generator ID"},{"value":"467 — Silver State South Solar Project shared solar/storage interconnection; 200 MW storage component","system":"CAISO queue position"},{"value":"56948","system":"FERC MBR EIA record"},{"value":"56949","system":"FERC MBR EIA record"},{"value":"EG24-290-000","system":"FERC docket"},{"value":"CAISO","system":"ISO/RTO"}] — Public Queue Report · confidence: medium - Identifiers: [{"value":"67734","system":"EIA plant ID"},{"value":"SSSB","system":"FERC/EIA generator ID"},{"value":"467 — Silver State South Solar Project shared solar/storage interconnection; 200 MW storage component","system":"CAISO queue position"},{"value":"56948","system":"FERC MBR EIA record"},{"value":"56949","system":"FERC MBR EIA record"},{"value":"EG24-290-000","system":"FERC docket"},{"value":"CAISO","system":"ISO/RTO"}] — Combined Filings · confidence: medium - Official project url: https://www.investor.nexteraenergy.com/~/media/Files/N/NEE-IR/investor-materials/supplemental-resources/generation-portfolios/2025/Copy%20of%20FPL_NextEra%20Energy%20Resources_Generation%20Portfolios_9302025.pdf — FPL_NextEra Energy Resources Generation Portfolios_9.30.2025.xlsx · confidence: medium - Owner name: NextEra Energy Resources, LLC — Source · confidence: medium - Owner name: NextEra Energy Resources, LLC — FPL_NextEra Energy Resources Generation Portfolios_9.30.2025.xlsx · confidence: medium - Description: Silver State South Storage is a 200 MW battery power plant in Clark County, Nevada. It is a transmission-connected, four-hour lithium-ion battery energy storage resource developed by NextEra Energy Resources and interconnecting at the Primm 220 kV Substation on the CAISO-controlled grid. The facility shares a point of interconnection with a solar resource. — Source · confidence: medium - Parties: [{"relationship":"Registered utility and project seller","name":"Silver State South Storage, LLC","official_url":null},{"relationship":"Developer and parent owner","name":"NextEra Energy Resources, LLC","official_url":"https://www.nexteraenergyresources.com/"},{"relationship":"Contract counterparty","name":"Southern California Edison Company","official_url":"https://www.sce.com/"}] — FPL_NextEra Energy Resources Generation Portfolios_9.30.2025.xlsx · confidence: medium - Identifiers.2: {"value":"467 — Silver State South Solar Project shared solar/storage interconnection; 200 MW storage component","system":"CAISO queue position"} — Public Queue Report · confidence: medium - Identifiers.5: {"value":"EG24-290-000","system":"FERC docket"} — Combined Filings · confidence: medium - Identifiers.6: {"value":"CAISO","system":"ISO/RTO"} — Source · confidence: high - Parties.0: {"relationship":"Registered utility and project seller","name":"Silver State South Storage, LLC","official_url":null} — Source · confidence: high - Parties.1: {"relationship":"Developer and parent owner","name":"NextEra Energy Resources, LLC","official_url":"https://www.nexteraenergyresources.com/"} — Source · confidence: medium - Parties.1: {"relationship":"Developer and parent owner","name":"NextEra Energy Resources, LLC","official_url":"https://www.nexteraenergyresources.com/"} — FPL_NextEra Energy Resources Generation Portfolios_9.30.2025.xlsx · confidence: medium - Interconnection: Primm 220 kV Substation on the CAISO-controlled grid; shared point of interconnection with a solar resource — Source · confidence: high - Unit configuration: One generating unit: 200 MW lithium-ion battery energy storage system with four-hour duration — Source · confidence: medium - Duration hours: 4 — Source · confidence: high - Power mw: 200 — Source · confidence: high - Energy mwh: 800 — Source · confidence: medium - Kind: bess — Source · confidence: high - Kind: bess — Source · confidence: high - Significance: Silver State South Storage is a 200 MW, four-hour, transmission-connected lithium-ion battery resource sharing a point of interconnection with a solar facility at CAISO's Primm 220 kV Substation. — Source · confidence: high - Description: Silver State South Storage is a 200 MW battery energy-storage facility in Clark County, Nevada, with one 200 MW generating unit. The four-hour lithium-ion resource was developed by NextEra Energy Resources and is operated by Silver State South Storage, LLC. It began commercial operation on April 1, 2025, and is connected to the CAISO-controlled grid at the Primm 220 kV Substation. The related 250 MW AC Silver State South solar project was sold by First Solar to a NextEra Energy Resources subsidiary on May 27, 2014; that transaction was for the solar project and does not establish a separate sale of the storage facility. — Source · confidence: medium - Description: Silver State South Storage is a 200 MW battery energy-storage facility in Clark County, Nevada, with one 200 MW generating unit. The four-hour lithium-ion resource was developed by NextEra Energy Resources and is operated by Silver State South Storage, LLC. It began commercial operation on April 1, 2025, and is connected to the CAISO-controlled grid at the Primm 220 kV Substation. The related 250 MW AC Silver State South solar project was sold by First Solar to a NextEra Energy Resources subsidiary on May 27, 2014; that transaction was for the solar project and does not establish a separate sale of the storage facility. — NextEra Energy Newsroom - News Releases · confidence: medium - Quality notes: ["The May 27, 2014 transaction was expressly described as the sale of a 250 MW AC solar project, so it should not be treated as a separately priced acquisition of the 200 MW storage facility.","The storage contract's costs and amended terms were confidential. No public sale consideration, financing amount, lender, or financing-close date was identified.","No battery OEM or storage-specific EPC contractor, expansion, retirement, or repowering event was identified. First Solar's EPC role in the cited transaction applies to the related solar project, not expressly to the battery system."] — Source · confidence: medium - Financing summary: NextEra's 2025 generation portfolio lists Silver State South Energy Storage as a 200 MW, 2025 in-service, solar-coupled battery project with ITC and DMI/Project Debt financing. DMI is identified in NextEra portfolio materials as Differential Membership Interest; no debt amount, lender, financing-close date, tax-equity amount, or sale consideration is disclosed. The May 2014 solar-project sale had undisclosed transaction terms and is distinct from storage financing. — florida power & light company generation portfolio · confidence: medium - Financing summary: NextEra's 2025 generation portfolio lists Silver State South Energy Storage as a 200 MW, 2025 in-service, solar-coupled battery project with ITC and DMI/Project Debt financing. DMI is identified in NextEra portfolio materials as Differential Membership Interest; no debt amount, lender, financing-close date, tax-equity amount, or sale consideration is disclosed. The May 2014 solar-project sale had undisclosed transaction terms and is distinct from storage financing. — NextEra Energy Generation Portfolio_12312022.xlsx · confidence: medium - Financing summary: NextEra's 2025 generation portfolio lists Silver State South Energy Storage as a 200 MW, 2025 in-service, solar-coupled battery project with ITC and DMI/Project Debt financing. DMI is identified in NextEra portfolio materials as Differential Membership Interest; no debt amount, lender, financing-close date, tax-equity amount, or sale consideration is disclosed. The May 2014 solar-project sale had undisclosed transaction terms and is distinct from storage financing. — Source · confidence: medium - Financing summary: NextEra's 2025 generation portfolio lists Silver State South Energy Storage as a 200 MW, 2025 in-service, solar-coupled battery project with ITC and DMI/Project Debt financing. DMI is identified in NextEra portfolio materials as Differential Membership Interest; no debt amount, lender, financing-close date, tax-equity amount, or sale consideration is disclosed. The May 2014 solar-project sale had undisclosed transaction terms and is distinct from storage financing. — NextEra Energy Newsroom - News Releases · confidence: medium - Timeline: [{"event":"Related solar-project acquisition and sale","date":"2014-05-27","detail":"First Solar completed the sale of the 250 MW AC Silver State South Solar Project to a subsidiary of NextEra Energy Resources. Transaction terms were not disclosed; the cited release does not identify a separate sale of the storage facility."},{"event":"Initial storage reliability contract","date":"2022-12-20","detail":"Southern California Edison and the seller executed an initial option contract for the Silver State South Storage project, with an expected initial delivery date of June 1, 2024."},{"event":"Interconnection-related contract amendment","date":"2024-03-25","detail":"SCE filed for approval of an amended and restated storage contract after interconnection-facilities work delayed the project beyond its original 2024 delivery target."},{"event":"Regulatory approval of amended contract","date":"2024-07-11","detail":"The California Public Utilities Commission approved SCE's 200 MW amended and restated Mid-Term Reliability contract with Silver State South Storage, LLC. Expected delivery was moved to June 1, 2025, under a 15-year RA-with-financial-settlement arrangement."},{"event":"Commercial operation","date":"2025-04-01","detail":"EIA 860M-derived plant data identifies April 1, 2025 as the first-unit online date for the 200 MW battery plant."},{"event":"In-service and financing classification","date":"2025","detail":"NextEra's generation portfolio lists Silver State South Energy Storage as a 200 MW battery project in service in 2025 and financed through ITC and DMI/Project Debt."}] — NextEra Energy Newsroom - News Releases · confidence: medium - Timeline: [{"event":"Related solar-project acquisition and sale","date":"2014-05-27","detail":"First Solar completed the sale of the 250 MW AC Silver State South Solar Project to a subsidiary of NextEra Energy Resources. Transaction terms were not disclosed; the cited release does not identify a separate sale of the storage facility."},{"event":"Initial storage reliability contract","date":"2022-12-20","detail":"Southern California Edison and the seller executed an initial option contract for the Silver State South Storage project, with an expected initial delivery date of June 1, 2024."},{"event":"Interconnection-related contract amendment","date":"2024-03-25","detail":"SCE filed for approval of an amended and restated storage contract after interconnection-facilities work delayed the project beyond its original 2024 delivery target."},{"event":"Regulatory approval of amended contract","date":"2024-07-11","detail":"The California Public Utilities Commission approved SCE's 200 MW amended and restated Mid-Term Reliability contract with Silver State South Storage, LLC. Expected delivery was moved to June 1, 2025, under a 15-year RA-with-financial-settlement arrangement."},{"event":"Commercial operation","date":"2025-04-01","detail":"EIA 860M-derived plant data identifies April 1, 2025 as the first-unit online date for the 200 MW battery plant."},{"event":"In-service and financing classification","date":"2025","detail":"NextEra's generation portfolio lists Silver State South Energy Storage as a 200 MW battery project in service in 2025 and financed through ITC and DMI/Project Debt."}] — Source · confidence: medium - Timeline: [{"event":"Related solar-project acquisition and sale","date":"2014-05-27","detail":"First Solar completed the sale of the 250 MW AC Silver State South Solar Project to a subsidiary of NextEra Energy Resources. Transaction terms were not disclosed; the cited release does not identify a separate sale of the storage facility."},{"event":"Initial storage reliability contract","date":"2022-12-20","detail":"Southern California Edison and the seller executed an initial option contract for the Silver State South Storage project, with an expected initial delivery date of June 1, 2024."},{"event":"Interconnection-related contract amendment","date":"2024-03-25","detail":"SCE filed for approval of an amended and restated storage contract after interconnection-facilities work delayed the project beyond its original 2024 delivery target."},{"event":"Regulatory approval of amended contract","date":"2024-07-11","detail":"The California Public Utilities Commission approved SCE's 200 MW amended and restated Mid-Term Reliability contract with Silver State South Storage, LLC. Expected delivery was moved to June 1, 2025, under a 15-year RA-with-financial-settlement arrangement."},{"event":"Commercial operation","date":"2025-04-01","detail":"EIA 860M-derived plant data identifies April 1, 2025 as the first-unit online date for the 200 MW battery plant."},{"event":"In-service and financing classification","date":"2025","detail":"NextEra's generation portfolio lists Silver State South Energy Storage as a 200 MW battery project in service in 2025 and financed through ITC and DMI/Project Debt."}] — florida power & light company generation portfolio · confidence: medium - Commercial parties: [{"relationship":"Registered project company, seller, and operator","name":"Silver State South Storage, LLC","detail":"Named as the storage-project seller in SCE's approved contract and identified as the operator of the 200 MW EIA plant.","official_url":null},{"relationship":"Developer and parent owner","name":"NextEra Energy Resources, LLC","detail":"The California regulatory record identifies NextEra Energy Resources as the storage project's developer.","official_url":"https://www.nexteraenergyresources.com/"},{"relationship":"Offtake and reliability-contract counterparty","name":"Southern California Edison Company","detail":"SCE contracted for 200 MW of the storage resource under a Mid-Term Reliability contract with delivery beginning June 1, 2025.","official_url":"https://www.sce.com/"},{"relationship":"Related solar-project predecessor owner, seller, developer, and EPC provider","name":"First Solar, Inc.","detail":"First Solar developed and designed the related 250 MW AC Silver State South solar project, provided EPC services, and sold that solar project to a NextEra Energy Resources subsidiary in May 2014.","official_url":"https://www.firstsolar.com/"},{"relationship":"Interconnecting balancing authority and market operator","name":"California Independent System Operator","detail":"The storage resource interconnects with the CAISO-controlled grid at the Primm 220 kV Substation.","official_url":"https://www.caiso.com/"}] — NextEra Energy Newsroom - News Releases · confidence: medium - Commercial parties.1: {"relationship":"Developer and parent owner","name":"NextEra Energy Resources, LLC","detail":"The California regulatory record identifies NextEra Energy Resources as the storage project's developer.","official_url":"https://www.nexteraenergyresources.com/"} — Source · confidence: medium - Commercial parties.3: {"relationship":"Related solar-project predecessor owner, seller, developer, and EPC provider","name":"First Solar, Inc.","detail":"First Solar developed and designed the related 250 MW AC Silver State South solar project, provided EPC services, and sold that solar project to a NextEra Energy Resources subsidiary in May 2014.","official_url":"https://www.firstsolar.com/"} — NextEra Energy Newsroom - News Releases · confidence: medium - Commercial parties.4: {"relationship":"Interconnecting balancing authority and market operator","name":"California Independent System Operator","detail":"The storage resource interconnects with the CAISO-controlled grid at the Primm 220 kV Substation.","official_url":"https://www.caiso.com/"} — Source · confidence: medium - Timeline.0: {"event":"Related solar-project acquisition and sale","date":"2014-05-27","detail":"First Solar completed the sale of the 250 MW AC Silver State South Solar Project to a subsidiary of NextEra Energy Resources. Transaction terms were not disclosed; the cited release does not identify a separate sale of the storage facility."} — NextEra Energy Newsroom - News Releases · confidence: high - Timeline.1: {"event":"Initial storage reliability contract","date":"2022-12-20","detail":"Southern California Edison and the seller executed an initial option contract for the Silver State South Storage project, with an expected initial delivery date of June 1, 2024."} — Source · confidence: high - Timeline.2: {"event":"Interconnection-related contract amendment","date":"2024-03-25","detail":"SCE filed for approval of an amended and restated storage contract after interconnection-facilities work delayed the project beyond its original 2024 delivery target."} — Source · confidence: high - Timeline.5: {"event":"In-service and financing classification","date":"2025","detail":"NextEra's generation portfolio lists Silver State South Energy Storage as a 200 MW battery project in service in 2025 and financed through ITC and DMI/Project Debt."} — florida power & light company generation portfolio · confidence: medium ## Timeline - 2014-05-27 — Related solar-project acquisition and sale First Solar completed the sale of the 250 MW AC Silver State South Solar Project to a subsidiary of NextEra Energy Resources. Transaction terms were not disclosed; the cited release does not identify a separate sale of the storage facility. Source: NextEra Energy Newsroom - News Releases (https://newsroom.nexteraenergy.com/First-Solar-Completes-Sale-of-250MW-Silver-State-South-to-NextEra-Energy-Resources?l=12) - 2022-12-20 — Initial storage reliability contract Southern California Edison and the seller executed an initial option contract for the Silver State South Storage project, with an expected initial delivery date of June 1, 2024. Source: Source (https://docs.cpuc.ca.gov/PublishedDocs/Published/G000/M533/K188/533188700.PDF) - 2024-03-25 — Interconnection-related contract amendment SCE filed for approval of an amended and restated storage contract after interconnection-facilities work delayed the project beyond its original 2024 delivery target. Source: Source (https://docs.cpuc.ca.gov/PublishedDocs/Published/G000/M533/K188/533188700.PDF) - 2024-07-11 — Regulatory approval of amended contract The California Public Utilities Commission approved SCE's 200 MW amended and restated Mid-Term Reliability contract with Silver State South Storage, LLC. Expected delivery was moved to June 1, 2025, under a 15-year RA-with-financial-settlement arrangement. Source: Source (https://docs.cpuc.ca.gov/PublishedDocs/Published/G000/M533/K188/533188700.PDF) ## Sources - [NextEra Energy Newsroom - News Releases](https://newsroom.nexteraenergy.com/First-Solar-Completes-Sale-of-250MW-Silver-State-South-to-NextEra-Energy-Resources?l=12) — newsroom.nexteraenergy.com · tier other - [Public Queue Report](https://www.caiso.com/documents/publicqueuereport.xlsx) — caiso.com · tier other - [Combined Filings](https://www.regulations.gov/document/FERC-2024-1281-0001) — regulations.gov · tier regulatory - [florida power & light company generation portfolio](https://www.investor.nexteraenergy.com/~/media/Files/N/NEE-IR/investor-materials/supplemental-resources/generation-portfolios/2025/Copy%20of%20FPL_NextEra%20Energy%20Resources%20Generation%20Portfolios_9302025.pdf) — investor.nexteraenergy.com · tier other - [Source](https://docs.cpuc.ca.gov/PublishedDocs/Published/G000/M533/K188/533188700.PDF) — docs.cpuc.ca.gov · tier regulatory - [NextEra Energy Resources | Mount Vernon Battery Storage | FAQ](https://www.nexteraenergyresources.com/mount-vernon-battery-storage/faq.html) — nexteraenergyresources.com · tier other - [NextEra Energy Resources | Key Energy Storage | FAQ](https://www.nexteraenergyresources.com/key-energy-storage/faq.html) — nexteraenergyresources.com · tier other - [NextEra Energy Generation Portfolio_12312022.xlsx](https://www.investor.nexteraenergy.com/~/media/Files/N/NEE-IR/NEE%20Generation%20Portfolio_12312022.pdf) — investor.nexteraenergy.com · tier other - [Source](https://www.caiso.com/documents/metering-exemption-listing-report-2026.pdf) — caiso.com · tier other ## Data quality - The May 27, 2014 transaction was expressly described as the sale of a 250 MW AC solar project, so it should not be treated as a separately priced acquisition of the 200 MW storage facility. The storage contract's costs and amended terms were confidential. No public sale consideration, financing amount, lender, or financing-close date was identified. No battery OEM or storage-specific EPC contractor, expansion, retirement, or repowering event was identified. First Solar's EPC role in the cited transaction applies to the related solar project, not expressly to the battery system. --- Canonical page: https://askthegrid.com/assets/facilities/silver-state-south-storage Source: Ask the Grid — https://askthegrid.com/