The demand forecast source data is used similarly but slightly differently in each of the Council’s power system models. Due to the differences of model fidelity and focus, each model requires slightly different forms of the same source information.
Regional Portfolio Model
The methodology for converting the source forecast into information for the Regional Portfolio Model can use as load futures was discussed in the System Analysis Advisory Committee
The same source data is used but in different detail in GENESYS. Regional demand data is input on an hourly basis and is sampled in lock step with the associated hydro runoff data and wind data per the methodology in use for aligning climate change data for the plan. Demand data used for external to the region comes from the same sources as the AURORA data as described below.
For regional loads, AURORA demand assumptions within the region are the same as in the Redeveloped GENESYS with the climate change loads shaped proportionally to each zone. For demand forecasts external to the region WECC-wide forecast, some loads were updated from the AURORA default and others were left the same. The default AURORA forecast uses the following data sources: USDOE-EIA Form 826, USFERC Form 714, Statistics Canada. The modifications to the default are primarily for some of California, British Columbia and Alberta demand.
For the state of California, from 2019 to 2030 annual loads were updated to what reporting by the California Energy Commission (CEC) Form 1.5a. The hourly load shapes for California zones, were supported by the following: for 2021-2030 loads, we used investor-owned utility hourly filings with CEC. For 2031-2054 loads, load shapes from 2030. For public utilities in California the CEC annual energy forecast of energy and peaks and the default hourly shapes in Aurora were used in conjunction to create the forecast.
For British Columbia, the October 2019 filed load forecasts with Canadian regulatory agencies is used as a data source for the update. The load forecast labeled diversification is used from a filing by Alberta Electric System Operator dated October 2019 for the Alberta load forecast.
 Each zone contains demand and resources and represent a balancing authority or a subset of a larger balancing authority with significant transmissions limitations within it.