CAISO Battery Revenue Index
Estimated revenue for every California battery. Free.

Grid-scale batteries are California's fastest-growing power resource, but how much money each project actually makes is locked behind expensive subscriptions. This index estimates monthly day-ahead energy arbitrage revenue for every utility-scale battery in CAISO from public data: EIA-923 monthly charge/discharge energy, shaped by the CAISO fleet's 5-minute dispatch and priced at each plant's own grid node.

The fleet is earning less per kW — by design

Every new battery flattens the very price spreads the fleet feeds on. The benchmark line shows what a perfect-foresight 4-hour battery at the average node could have earned in the day-ahead market; the bars show what the reporting fleet is estimated to have actually earned.

Fleet revenue vs. perfect foresight ($/kW-month)

Estimated DA energy arbitrage, MW-weighted fleet average · benchmark: perfect TB4 at battery nodes

Installed battery capacity in CAISO (MW)

Cumulative nameplate MW online, from EIA-860M commercial operation dates

Where the money is

Marker size = nameplate MW; color = estimated trailing revenue in $/kW-year. Gray rings are batteries without monthly EIA reporting (typically small or recently commissioned). Click a marker for detail.

$/kW-year (TTM)

< 15

15 – 25

25 – 35

> 35

no monthly data

Project leaderboard

Estimated day-ahead energy revenue per project. Capture compares each project's estimate to a perfect-foresight battery moving the same energy at the same node — a measure of dispatch quality. Click any row for monthly detail. Hybrid projects (co-located solar) are flagged: their charging cost is largely internal PV, so treat their numbers as indicative.

#	Project	County	MW	Hrs	Online	$/kW-mo	$/kW-yr	Capture	Cycles/day

Methodology & honest caveats

Everything here is an estimate built entirely from public data — no settlement data, no confidential information. The point is a credible, free benchmark where none exists.

How it works

Roster. Every operating battery in the CAISO balancing authority from EIA-860M: capacity, energy, location, commercial operation date, operator.
Monthly energy. Each plant's monthly gross discharge and charging MWh from the EIA-923 energy storage schedule (~92% of fleet MW reports monthly).
Node matching. Each plant is matched to the nearest geocoded CAISO pricing node (generation nodes preferred within 15 km), reusing the node map behind the Battery Locator.
Hourly shaping. The plant's monthly discharge and charge energy is allocated to hours in proportion to the CAISO fleet's actual 5-minute battery dispatch that month, then priced at the plant's own node's hourly day-ahead LMP — i.e. a volume-weighted average price for its discharge and its charge.
Price history. Nodal LMPs are used from 2023 onward (CAISO OASIS only retains ~39 months). Earlier months are priced at each plant's TAC-area hourly day-ahead price (PG&E / SCE / SDG&E), which mutes locational differences between projects — treat pre-2023 project rankings as approximate.
Benchmarks. Capture divides the estimate by a perfect-foresight dispatch of the same monthly energy at the same node (best-priced hours each day, at nameplate power). The market benchmark line uses a perfect TB4: charge the 4 cheapest hours (grossed up by 1/0.86 round-trip efficiency), discharge the 4 most expensive.

What this deliberately excludes

Ancillary services, RA capacity payments and hedges. This is day-ahead energy value only. For many projects, AS and resource adequacy contracts are a large share of total revenue, and real-time trading can add or subtract more.
Plant-specific dispatch. Individual dispatch profiles are not public; the fleet shape is applied to every plant. Differences between projects therefore come from their node's prices and their monthly energy volumes — not from their trader's hour-by-hour skill.
Hybrid accounting. Co-located (hybrid) batteries often charge from their own solar; their effective charging cost differs from the nodal LMP used here. They are flagged throughout.
EIA data quality. Monthly EIA-923 figures are survey responses and occasionally revised; nameplate energy (MWh) in EIA-860M is unreliable for some plants, so duration-derived stats are suppressed where implausible.

Sources: EIA-860M, EIA-923, CAISO OASIS day-ahead LMPs, CAISO Today's Outlook. The full dataset behind this page is open: index_data.json. Corrections welcome — email me.

CAISO Battery Revenue IndexEstimated revenue for every California battery. Free.