Abstract: A process for identifying patterns of electric energy consumption and demand in a facility and determining possible changes in the facility for energy conservation, using monthly electric billing data over the years to ascertain billing periods and KW and Kwh consumption and to obtain from the ration Kwh/KW the hours use of peak demand per week, which provides a useful estimate of hours of use for the facility. Together with minimal facility data (just area data) and daily maximum and minimum outside temperature data, the process identifies patterns of consumption and demand, and then uses conveyance of an empirical analysis to disaggregate billing data into lighting, power, and HVAC end-use categories, and a statistical analysis, including regression, to separate the same billing data into usage and temperature-dependent components. Proposed retrofits for energy conservation are indicated and then implementable. Actual savings are calculated and used to further refine the model of actual facility operation.