GHG Allowance Price Index

Daily greenhouse-gas allowance price index used as a CAISO market-clearing input.

Prices data CAISO market

Query with the agent

Native record

event_time

daily publication cadence

Evidence

Observed market data

Published observations from the named source

Time basis

Point-in-time records

UTC · event_time

Overview

This is an input price, not a nodal LMP or the nodal GHG LMP component.

Query contract

Preserve one canonical row per (event_time) before aggregating.

Analysis rules

Group only after preserving the declared grain: event_time.

Access

Query from your own tools

Use the guarded HTTP endpoint directly, or connect an MCP client and load the dataset contract with describe_data before calling query_data.

CAISO MCP API reference

HTTP endpoint

POST /api/v1/datasets/caiso_ghg_allowance/query

Schema3

Column

Type

event_timeDateTime64(6, 'UTC')

ghg_prc_idxNullable(Float64)

ingested_atDateTime64(6, 'UTC')

Sample data

event_time	ghg_prc_idx	ingested_at
2026-09-03 07:00:00.000000	33.35	2026-09-03 15:00:39.694771
2026-09-02 07:00:00.000000	33.74	2026-09-03 15:00:39.694771
2026-09-01 07:00:00.000000	33.69	2026-09-03 15:00:22.326251
2026-08-31 07:00:00.000000	33.35	2026-09-02 15:00:26.001992
2026-08-30 07:00:00.000000	33.35	2026-09-01 15:18:10.712373
2026-08-29 07:00:00.000000	33.35	2026-08-31 15:00:23.321682
2026-08-28 07:00:00.000000	33.18	2026-08-30 15:00:30.380341
2026-08-27 07:00:00.000000	32.92	2026-08-29 15:00:20.805691
2026-08-26 07:00:00.000000	32.98	2026-08-28 15:00:20.874668
2026-08-25 07:00:00.000000	32.61	2026-08-27 15:00:29.917935
2026-08-24 07:00:00.000000	32.96	2026-08-26 15:00:21.503679
2026-08-23 07:00:00.000000	32.96	2026-08-25 15:00:22.295659
2026-08-22 07:00:00.000000	32.96	2026-08-24 15:00:28.870933
2026-08-21 07:00:00.000000	33.49	2026-08-23 15:00:28.281668
2026-08-20 07:00:00.000000	33.39	2026-08-22 15:00:28.969716
2026-08-19 07:00:00.000000	33.47	2026-08-21 15:00:22.192503
2026-08-18 07:00:00.000000	33.25	2026-08-20 15:00:28.935981
2026-08-17 07:00:00.000000	33.32	2026-08-19 15:00:26.738234
2026-08-16 07:00:00.000000	33.32	2026-08-18 15:00:21.370194
2026-08-15 07:00:00.000000	33.32	2026-08-17 15:00:28.276036
2026-08-14 07:00:00.000000	33.34	2026-08-16 15:00:28.046662
2026-08-13 07:00:00.000000	33.43	2026-08-15 15:00:27.228744
2026-08-12 07:00:00.000000	33.4	2026-08-14 15:00:22.078359
2026-08-11 07:00:00.000000	33.3	2026-08-13 15:00:30.477549
2026-08-10 07:00:00.000000	33.16	2026-08-12 15:00:27.950972

Coverage

51.6% complete2,048 gap days2,185 days with data

Show coverage history ▾

Coverage: 51.6%Days with data: 2,185Gaps: 2,048

2026

2025

2024

2023

2022

2021

2020

2019

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2016

2015

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Related prices data

Related prices data
Dataset	Description
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CAISO Real-Time PricesCAISO · 5-minute (RTD)	CAISO real-time locational marginal prices, one row per interval and location. 15.76B rows, 2016-01 to now. Carries price_usd_mwh plus energy_usd_mwh, congestion_usd_mwh, loss_usd_mwh and ghg_usd_mwh — CAISO is the only market here that publishes a greenhouse-gas component. Locations are node (26k — including the TH_ trading hubs such as TH_SP15_GEN-APND; CAISO has no 'hub' kind), interface (the ties), zone (6 aggregates only); location_id joins atg.caiso_locations for the readable name, and kind is carried inline so a hub-only or zone-only question needs no join at all. Every market's real-time price table in this catalog has these same column names, so a cross-market price comparison is a UNION rather than a per-ISO rewrite. Revisions are already collapsed — read it plainly.
Day-Ahead LMPCAISO · hourly (DAM)	Hourly locational marginal prices from CAISO's day-ahead market for pricing nodes across the California ISO footprint. These are cleared market outcomes for future delivery, not forecasts. Comparing the exact same delivery hour and pricing node with five-minute RTD prices shows day-ahead versus real-time divergence. The official source is CAISO OASIS.
Fuel Region Gas PricesCAISO · Daily (gas day)	CAISO's daily natural-gas price for each of its fuel regions, in $/MMBtu. CAISO posts this as FUEL REGION \| GAS INDEX \| TRANSPORT \| TOTAL, and the value here is that total: a published gas index plus a transport adder, i.e. the delivered cost of gas to that region, not a hub spot assessment. It is the number CAISO uses to reference and floor gas-fired energy bids, so it is the fuel-cost input underneath thermal offer behavior across the West. 201 fuel regions are currently active across 27 electric subregions, reaching well beyond California: Waha and El Paso Permian in West Texas, Opal, Kern River, Cheyenne, CIG and the San Juan points in the Rockies, Malin, Stanfield, Northwest Sumas and Kingsgate in the Pacific Northwest, Alberta AECO in Canada, and the SoCal Citygate and PG&E Citygate burner-tip regions in California. Receipt-point regions such as Waha (FRWHA1-3), El Paso Permian (FREPP1-4), Opal, Malin and Sumas track the underlying published index closely, because their transport adder is small; citygate regions are burner-tip costs and spread widely, so they are not interchangeable with a hub price — on 2026-08-20 the 40 region ids named SoCal Citygate ranged from 4.43 to 8.15 $/MMBtu on the same day. Region ids ending in GHG carry a California carbon-allowance adder on top and are a different quantity again. Negative prices are real and are concentrated in the takeaway-constrained Permian regions: 0.97% of rows are below zero, to a minimum of -10.51 $/MMBtu. Rows are stamped hourly, 24 per region per gas day, but the price is constant across a gas day, and the gas day is the America/Los_Angeles calendar date — it steps at Pacific midnight, so daily rollups must use toDate(event_time, 'America/Los_Angeles'). The current gas day is partial until the next 14:30 UTC pull, though its price is already complete. History runs from 2015-02-01 and is continuous and complete from 2026-02-01 onward; before that date it covers 1,972 of 4,018 days in whole-month blocks (February through April, June, September and November of each year), so a pre-2026 average over an arbitrary window is an average over the months that are present, not over the period requested. Hub attribution is INFERRED from CAISO's region coding, not published: CAISO's monthly fuel-region posting lists region ids with their index, transport and total and no hub names at all, and FRWHA does not appear in it — so 'Waha' here reads the id, corroborated by the price sitting where Waha sits against Henry Hub, rather than by a CAISO mapping. Treat a region as the delivered cost CAISO assigns to it; do not cite it as a hub assessment. This dataset is FUEL-COST CONTEXT, not market settlement data, and is queryable from every active grid scope: a question asked under ERCOT about West Texas gas cost answers from the Waha-region ids here, said as delivered fuel cost. The official source is CAISO OASIS report PRC_FUEL.