Resolves as YES if there is strong evidence that cumulative installed U.S. utility‑scale battery storage power capacity reached at least 90 gigawatts (GW) before January 1st 2030.

For the purposes of this market:

• “Cumulative installed U.S. utility‑scale battery storage power capacity” means the total nameplate power capacity (in MW or GW) of all grid‑connected, utility‑scale battery energy storage systems in the United States (stand‑alone or co‑located with generation), as of the end of calendar year 2029.

• “Utility‑scale” is intended to match the definition used by the primary data source (typically ≥1 MW and connected to the transmission or distribution grid as a power‑sector asset, rather than behind‑the‑meter customer equipment).

• Primary reference for resolution: the national‑level totals for operating U.S. utility‑scale battery storage power capacity published by the U.S. Energy Information Administration (EIA), e.g. in the Preliminary Monthly Electric Generator Inventory, Electric Power Monthly, or any successor series that clearly reports total U.S. battery storage capacity in MW or GW.

  • If EIA’s best available estimate for year‑end 2029 shows ≥ 90 GW of U.S. utility‑scale battery storage power capacity, this market resolves YES.

  • If it clearly shows < 90 GW, this market resolves NO.

• Fallback sources:
  If the exact EIA series normally used becomes unavailable, obviously inconsistent, or is not updated to include year‑end 2029, the resolver should use the best available national‑level dataset that:

  1. Covers the whole United States with a single cumulative figure for operating battery storage power capacity (GW or MW),

  2. Clearly distinguishes battery storage from pumped hydropower and other non‑battery storage, and

  3. Is produced by a reputable statistical or analytical organization (e.g. another EIA publication, a U.S. government report, a major intergovernmental or research body, or a widely‑cited industry analytics firm).

  If multiple such sources disagree slightly, the resolver should pick the one that is most methodologically transparent and internally consistent and explain the choice in a comment.

Clarifications and edge cases

• Timing:
  The condition is about capacity that is in service as of the end of 2029 (i.e., projects that have reached commercial operation and are counted as installed by that date), even if the confirming data is only published in 2030 or later.

• Geography:
  “United States” here means the 50 U.S. states plus the District of Columbia. If the chosen data series either includes or excludes U.S. territories, it should be used consistently across years; the resolver should not mix incompatible series.

• Technology scope:

  • Included: grid‑connected battery energy storage systems of any chemistry (e.g. lithium‑ion, flow batteries, sodium‑based, etc.), whether stand‑alone or co‑located with solar, wind, or other generators.

  • Excluded: pumped hydropower storage, compressed‑air or other mechanical storage, flywheels, hydrogen, or any storage that is not reported under “battery storage” (or a clearly equivalent category) in the chosen data series.

  • If a source bundles batteries with other storage technologies in a way that cannot be cleanly separated, that source should not be used unless no better alternative exists, in which case the resolver should explain the reasoning.

• Metric:
  The market is about power capacity (GW or MW), not energy capacity (GWh or MWh). If a source reports both, the resolver should use the power figure.

• Revisions and conflicting data:
  If figures are later revised, the resolver should use the most recent, methodologically consistent estimate available at the time of resolution. If different reputable sources disagree significantly about whether the 90‑GW threshold was reached, the resolver should favor the source that best matches the definitions above and document the decision in a comment.
  
  

Intuition / scale (not part of resolution):

• The 90‑GW threshold is chosen to be roughly a “doubling from the mid‑2020s baseline” using EIA’s definition of utility‑scale battery storage, making this market hinge on whether the current boom in grid batteries can sustain itself through the rest of the decade under evolving policy, supply‑chain, and demand conditions.