# 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 2026-08-27 06:00:00 $ interval_end_utc 2026-08-27 07:00:00 $ tac_area_name 'WALCDSW' $ load 335.0 ``` ## Dataframe Manifest | Dataframe Name | CAISO Load Hourly | |--------------------------------|--------------------------------------------------------------------------------------| | Dataframe ID | [caiso_load_hourly](../dataframes/CAISO/caiso_load_hourly.md) | | 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](../../../index.md) | | 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](../../dataframes/CAISO/caiso_lmp_day_ahead_hourly.md)
[CAISO:caiso_lmp_real_time_15_min](../../dataframes/CAISO/caiso_lmp_real_time_15_min.md)
[CAISO:caiso_lmp_real_time_5_min](../../dataframes/CAISO/caiso_lmp_real_time_5_min.md)
[CAISO:caiso_fuel_prices](../../dataframes/CAISO/caiso_fuel_prices.md)
[CAISO:caiso_fuel_regions](../../dataframes/CAISO/caiso_fuel_regions.md)
[CAISO:caiso_load](../../dataframes/CAISO/caiso_load.md)
[CAISO:caiso_load_hourly](../../dataframes/CAISO/caiso_load_hourly.md)
[CAISO:caiso_fuel_mix](../../dataframes/CAISO/caiso_fuel_mix.md)
[CAISO:caiso_renewables_hourly](../../dataframes/CAISO/caiso_renewables_hourly.md)
[CAISO:caiso_curtailed_non_operational_generator_report](../../dataframes/CAISO/caiso_curtailed_non_operational_generator_report.md)
[CAISO:caiso_outages_aggregated_hourly](../../dataframes/CAISO/caiso_outages_aggregated_hourly.md)
[CAISO:openmeteo_temperature_daily](../../dataframes/CAISO/openmeteo_temperature_daily.md)
[CAISO:eia860m_generators](../../dataframes/CAISO/eia860m_generators.md)
[CAISO:us_ba_boundaries](../../dataframes/CAISO/us_ba_boundaries.md)
| **Build Commands:** ``` doit ```