Electric water heating for single-family residences: group load research and analysis. Final report

A computer program incorporating a behavior model and physical model was developed to estimate the diversified electrical demand of electric water heaters on an electric utility system, based on demographic variables of customers in its service area and on relevant physical variables. A vast amount of 15-minute magnetic-tape-recorded test data for the 12 months ended January, 1980 was gathered from 110 single-family residences (10 per utility) by 11 utilities scattered throughtout the continental United States. An econometric (behavioral) model for predicting hourly hot water consumption of single-family residence was developed. The explanatory variables of the model account for approximately 70% of the variation in hot water consumption found in each time period in the tests. A physical model was developed which incorporates the behavioral model, a thermodynamic model of an electric water heater and a Monte Carlo simulation in order to predict the total hourly diversified electrical demands placed on a utility grid by water heaters. By specifying times when power will be inhibited to the water heater the utility can simulate any water heater load control strategy. A ''data base'', or master file, of edited gallons of water test data was prepared; it includes each test customer for themore » 12-month period, plus all other magnetic-tape-recorded data for the month of August 1979 only - all in pulse count form. Also, a ''load profile'' data of this same information, on an hourly basis, in engineering units, was prepared for each customer. A computer tape of each of these two data files was supplied to EPRI. 43 figs., 30 tabs.« less