3.7 Interaction with Electric Model
Once the end-use model has projected energy demands across the economy over the model time horizon for each of the individually modeled structural classes within each region, an hourly load shape for electricity demand is calculated for each end-use.
For space heating and cooling, the load shape is based on the hourly temperature profile for a given year. All load shapes, as well as renewable resource profiles, are based on the same representative year to ensure that the joint distribution is captured appropriately. In the buildings model, energy use for each temperature band was calculated to inform long-run average annual energy use. These same calculations are used to derive hourly energy consumption in the representative year.
For vehicle charging, the load shape is constructed as described above as a linear combination of three exogenous charging patterns. These patterns are specified for 24 diurnal hours, which are mapped onto the corresponding 8760 hours of the representative year. This same hourly profile is assumed to apply to non-passenger transportation uses of electricity.
For other building uses, including lighting, water heating, electronics, and appliances, and a generic industrial end-use, EPRI has developed a load shape library to describe typical diurnal profiles by season and day type (i.e. weekday vs. weekend)—see Figure 3‑17 for examples. These profiles are similarly mapped to the corresponding 8760 hours to generate annual load shapes.
These calculations result in a different aggregate load profile for each region in each time period as the load mix across end-uses changes. For this reason, the representative hour procedure described in Chapter 2 is repeated for each time step, generating a time-dependent set of representative hours to capture the changing relative distribution of load vs. wind and solar.
