U.S. Battery Storage Planned Additions, Next 12 Months

## What this measures

The nameplate capacity, in gigawatts, of utility-scale batteries that developers told EIA they plan to start operating in the 12 months after each report month. The reading for a month covers the next twelve: the August 2026 inventory counts units planned for September 2026 through August 2027.

## Why it matters

It is a forward read of grid storage: what is due to arrive on the U.S. grid over the next year, before it shows up in operating capacity (energy.battery_storage.operating_gw.us).

## How to read it

The August 2026 inventory listed 23.4 GW due by August 2027, against 19.6 GW a year earlier; the record is 24.4 GW in the December 2025 inventory. Plans run ahead of delivery: the December 2023 inventory listed 14.3 GW for 2024 and operating capacity grew 11.2 GW that year; the December 2024 inventory listed 18.2 GW for 2025 and capacity grew 15.7 GW. Higher means a larger pipeline due within a year. Compare it with the capacity actually added over the following twelve months to see how much arrives on schedule.

## What it does not say

Plans slip. Many projects are delayed, shrunk or cancelled, and the count includes units at every stage, from those still awaiting regulatory approval to those built but not yet in commercial operation. It is the developers' schedule as reported to EIA, not an EIA forecast. Each reading is fixed to its own monthly inventory; earlier readings are not revised.

## How it's built

Palanor reads the "Planned" sheet of each month's EIA-860M workbook and sums the nameplate capacity of units with technology "Batteries" whose planned operation month falls one to twelve months after the report month. History starts with the January 2019 inventory.

## Source

U.S. Energy Information Administration, Form EIA-860M Preliminary Monthly Electric Generator Inventory, Planned sheet (eia.gov/electricity/data/eia860m). EIA data are in the public domain.