Project New Horizon (Copper Crossing Phase 2) — 5 MW / 50 MWh iron flow battery LDES pilot, Florence, Arizona
ESS Tech signs 10-year energy storage agreement with Salt River Project for a 5 MW / 50 MWh iron flow battery pilot at SRP's Copper Crossing Energy and Research Center in Florence, AZ. Google provides partial funding via cost-sharing; EPRI serves as independent technical oversight. Batteries deliver 10-hour duration using ESS Energy Base platform (iron, salt, water chemistry). Manufacturing begins 2026; delivery targeted December 2027. Part of SRP's broader Project New Horizon multi-technology LDES portfolio, which also includes CMBlu Energy's Desert Blume pilot (5 MW / 50 MWh organic flow). ESS batteries carry 25-year life expectancy and >90% domestic content.
Deal Value
5MW
Capacity
50MWh
Storage
Iron Flow Battery (LDES)
Technology
AZ
Location
Deal Details
- Deal Type
- Energy Storage Agreement
- Seller / Sponsor
- ESS Tech, Inc.
- Buyer / Financier
- Salt River Project (SRP)
- Offtaker
- Salt River Project (SRP)
- Stage
- Development
- Source
- BusinessWire / ESS Tech
Service Providers
Advisory & Legal
- technicalOversight
- Electric Power Research Institute (EPRI)
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