The hourly, normalized load shape for combined residential equipment use is shown in Figure 21, and is based on the ELCAP study of household electricity use in the Pacific Northwest (Pratt et al. 1989). In most situations, this profile is adequate for simulating all electric and gas end uses except space conditioning and hot water. However, because some individual end-use profiles are nearly constant (such as refrigerator and transformer loads) and some are highly dependent on time of day (such as the range and dishwasher), we have also developed a series of normalized hourly profiles for major appliances and MELs, shown in Figure 22 to Figure 29. Numerical values associated with these profiles can be found in the BA Analysis Spreadsheet posted on the BA Web site (http://www1.eere.energy.gov/buildings/building_america/perf_analysis.html). The hourly profiles for machine energy usage in the clothes washer and dishwasher are identical to those provided earlier in the section on DHW (see Figure 6 to Figure 9).
All hourly end-use profiles were taken from the ELCAP study, except the profile for “Miscellaneous Electric Loads,” which was derived by subtracting the energy consumption profiles for the major appliances from the combined profile for all equipment, assuming an all- electric, 1800-ft2, three-bedroom house in Memphis, Tennessee. Internal sensible and latent loads from appliances and plug loads shall be modeled using the same hourly profiles used for end-use consumption. Appliance loads may be modeled in either the living spaces or bedroom spaces, depending on their location in the Prototype.
Fraction of Total Daily Usage
0.1 0.09 0.08 0.07 0.06 0.05 0.04 0.03 0.02 0.01
10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Hour of Day
Figure 21. Total combined residential equipment profile (Pratt et al. 1989)