Dataframe: CAISO:caiso_load_hourly - CAISO Load Hourly

Description

Hourly (actuals) electricity load in the CAISO footprint, broken out by TAC area (Transmission Access Charge area / balancing authority).

This dataset provides grid operational context for the project. It sits alongside prices, fuel mix, and outage data as a demand-side conditioning variable rather than a spread leg or gas leg.

Data Dictionary

• interval_start_utc: TIMESTAMP Interval start, UTC.

• interval_end_utc: TIMESTAMP Interval end, UTC. Equal to the interval start plus one hour.

• tac_area_name: VARCHAR TAC area / balancing authority name. Long format - one row per area per interval.

• load: INTEGER Actual load, MW. Includes load from storage charging, unlike the 5-minute system-wide caiso_load dataset.

Notes

• Hourly granularity. The source (CAISO OASIS) retains roughly 39 months of history.

• The cached extract used here covers all TAC areas from 2018-01-01 onward, topped up daily.

• The load column counts storage charging as load; comparisons against caiso_load (which excludes it) will differ for that reason.

Data Preview

Rows: 1,944,693  |  Columns: 4  |  Cache: data/opensource/caiso_load_hourly.parquet

Sample rows

First and latest 5 rows by interval_start_utc.

interval_start_utc	interval_end_utc	tac_area_name	load
2018-01-01 08:00	2018-01-01 09:00	VEA-TAC	67.0
2018-01-01 08:00	2018-01-01 09:00	AZPS	2662.0
2018-01-01 08:00	2018-01-01 09:00	SDGE-TAC	2028.0
2018-01-01 08:00	2018-01-01 09:00	SCE-TAC	9494.0
2018-01-01 08:00	2018-01-01 09:00	PSEI	3028.0
…	…	…	…
2026-08-27 06:00	2026-08-27 07:00	TPWR	417.0
2026-08-27 06:00	2026-08-27 07:00	VEA-TAC	83.0
2026-08-27 06:00	2026-08-27 07:00	WALC	1301.0
2026-08-27 06:00	2026-08-27 07:00	WALCAEPCO	785.0
2026-08-27 06:00	2026-08-27 07:00	WALCDSW	335.0

Column summary

Column	Dtype	Nulls	Min	Max
interval_start_utc	Datetime[ns]	0	2018-01-01 08:00	2026-08-27 06:00
interval_end_utc	Datetime[ns]	0	2018-01-01 09:00	2026-08-27 07:00
tac_area_name	String	0	AVA	WALCDSW
load	Float64	0	-13352.0	51292.0

DataFrame Glimpse

Rows: 1944693
Columns: 4
$ interval_start_utc <datetime[ns]> 2026-08-27 06:00:00
$ interval_end_utc   <datetime[ns]> 2026-08-27 07:00:00
$ tac_area_name               <str> 'WALCDSW'
$ load                        <f64> 335.0

Dataframe Manifest

Dataframe Name	CAISO Load Hourly
Dataframe ID	caiso_load_hourly
Data Sources	CAISO OASIS (SLD_FCST, ACTUAL)
Data Providers	CAISO
Links to Providers	http://oasis.caiso.com
Topic Tags	Load, Grid Context
Type of Data Access
How is data pulled?	src/pulls/pull_caiso_load_hourly.py via the open-source gridstatus library
Data available up to (min)	N/A
Data available up to (max)	N/A
Dataframe Path	data\opensource\caiso_load_hourly.parquet

Linked Charts:

• None

Pipeline Manifest

Pipeline Name	Project-Lab-Energy-Weather-Natgas-Quanto-CAISO
Pipeline ID	CAISO
Lead Pipeline Developer	Brian Nguyen
Contributors	Brian Nguyen, Claire Kim
Git Repo URL
Pipeline Web Page	Pipeline Web Page
Date of Last Code Update	2026-08-27 10:08:05
OS Compatibility	Windows, Linux, macOS
Linked Dataframes	CAISO:caiso_lmp_day_ahead_hourly CAISO:caiso_lmp_real_time_15_min CAISO:caiso_lmp_real_time_5_min CAISO:caiso_fuel_prices CAISO:caiso_fuel_regions CAISO:caiso_load CAISO:caiso_load_hourly CAISO:caiso_fuel_mix CAISO:caiso_renewables_hourly CAISO:caiso_curtailed_non_operational_generator_report CAISO:caiso_outages_aggregated_hourly CAISO:openmeteo_temperature_daily CAISO:eia860m_generators CAISO:us_ba_boundaries

Build Commands:

doit