Resolves as YES if there is strong evidence that total installed U.S. grid‑connected battery energy storage energy capacity reached at least 260 gigawatt‑hours (GWh) before January 1st 2030.

For the purposes of this market:

• Baseline and “doubling” threshold

  • For this market, the end‑2025 total installed U.S. battery energy storage capacity is fixed at 130 GWh (E₍₂₀₂₅₎ = 130 GWh).

  • This is an approximate, rounding‑friendly value based on current industry estimates for cumulative installed battery energy storage across all segments at the end of 2025.

  • “Doubles over 2025–2029” is therefore defined as total installed U.S. battery energy storage capacity reaching at least 260 GWh (2 × 130 GWh) at any point up to and including December 31st 2029.

  This market does not wait to see what ex‑post data says about the “real” 2025 total; the baseline of 130 GWh and the doubling threshold of 260 GWh are fixed constants for resolution.

• Metric

  • The metric is battery energy storage capacity, i.e. the maximum electrical energy (in MWh) that all operating grid‑connected battery storage systems in the U.S. can deliver from a full charge.

  • Resolution will be based on this cumulative capacity expressed in GWh (1 GWh = 1,000 MWh).

• Scope

  • Included: Grid‑connected electrochemical battery energy storage systems of any chemistry (lithium‑ion, sodium‑ion, flow batteries, etc.), whether stand‑alone or co‑located with generation, in all market segments (utility‑scale, commercial & industrial, community, residential) so long as they are counted in the chosen national‑level dataset.

  • Excluded: Pumped‑hydro storage, compressed‑air storage, hydrogen, flywheels, thermal storage, and any other non‑battery technologies; off‑grid and purely behind‑the‑meter batteries not captured in national storage statistics also do not count.

• Geography

  • “United States” means the 50 states plus the District of Columbia.

  • If the chosen dataset includes or excludes U.S. territories, it should do so consistently across all years; the resolver should not mix series with different geographic coverage.

• Primary data source

  The intended primary reference is the U.S. Energy Storage Monitor (ACP + Wood Mackenzie), or a clear successor, which publishes national totals for cumulative installed U.S. battery energy storage capacity in GWh.

  • If the latest available edition covering year‑end 2029 shows total U.S. cumulative battery energy storage capacity ≥260 GWh, this market resolves YES.

  • If it clearly shows <260 GWh, this market resolves NO.

• Fallback data source

  If the U.S. Energy Storage Monitor totals for 2029 are not available or are clearly unusable, the resolver should choose one alternative national‑level dataset that:

  1. Reports cumulative, installed battery (electrochemical) energy storage capacity in the United States in MWh/GWh for 2025 and 2029;

  2. Covers all segments, or at least clearly indicates which segments are included;

  3. Excludes non‑battery storage or allows batteries to be clearly separated.

  Example: a U.S. government or NREL compilation that aggregates EIA battery‑storage energy‑capacity data plus distributed storage estimates.

  The resolver should pick a single series, explain the choice in a comment, and use it consistently.

• Timing and “before January 1st 2030”

  • The key comparison is between December 31st 2025 (baseline, fixed at 130 GWh) and December 31st 2029.

  • The condition “before January 1st 2030” is satisfied if any data point with a reference date on or before December 31st 2029 shows total installed U.S. battery energy storage capacity ≥260 GWh.

  • Data can be published later; what matters is the reference date of the capacity value, not the publication date.

• Revisions and conflicting estimates

  • If the chosen dataset is revised, the resolver should use the most recent, methodologically consistent version of that dataset.

  • If multiple reputable datasets give slightly different 2029 totals, the resolver should choose the one that best matches the metric and scope above and apply the simple rule:

    • If best‑supported 2029 total ≥260 GWh → YES

    • Otherwise → NO
      
      

Intuition (not part of resolution):
The market is effectively “Will U.S. grid‑connected batteries reach at least 260 GWh by the end of 2029?”, which is very close to the current central forecast (~261 GWh). So it’s a direct bet on whether the present U.S. storage boom can stay on pace despite policy and supply‑chain headwinds.