Eolus Secures Milestone Payments for Arizona Solar+Storage

• Eolus’ Centennial Flats reaches key milestones in Arizona—500 MW solar plus 267 MW storage—after a 2022 sale, triggering progress-based payments tied to its landmark solar-plus-storage deal.

Swedish renewable energy developer Eolus received milestone payments tied to its Centennial Flats solar-plus-storage project in Arizona. The facility combines 500 MW of photovoltaic generation with 267 MW of battery storage.

Eolus sold Centennial Flats in 2022, marking the company’s first sale of a project that pairs solar generation with energy storage. The latest payments reflect progress under the terms of that transaction.

How did Eolus milestone payments advance Arizona’s Centennial Flats solar-plus-storage project?

• The milestone payments were triggered by agreed development and construction progress on Centennial Flats, helping convert project “build steps” into scheduled cash inflows.
  
• By tying payment timing to technical and regulatory milestones, the structure reduced schedule risk for Eolus while ensuring capital was released as the project moved from development toward energization.
  
• The payments supported downstream activities critical to a solar-plus-storage build—such as final engineering, procurement of major long-lead equipment, grid interconnection work, and construction mobilization.
  
• Funding the transition from development to execution improved the project’s ability to maintain contractor commitments and manage cost escalation during procurement and construction.
• The added liquidity helped finance integration work specific to storage deployments (battery system commissioning plans, battery performance testing, and system-level controls) rather than relying solely on earlier capital.
  
• Because the facility was sold in 2022 as part of Eolus’ first transaction involving a combined solar-and-storage asset, milestone payments effectively aligned ongoing seller responsibilities (handover conditions, completion criteria) with the buyer’s commissioning timeline.
  
• The arrangement also helped the buyer and Eolus manage remaining deliverables toward commercial operation, since payments were linked to demonstrated progress rather than only upfront transfers.
• Overall, milestone payments advanced the project by providing stepwise capital, de-risking the build schedule, and ensuring resources stayed available through key phases leading up to commissioning of the combined 500 MW solar and 267 MW storage installation.