Estimating nonprocess energy from building energy consumption

From this research, an important technique for estimating the nonprocess energy (also known as overhead energy) in industrial and manufacturing buildings was examined. The building energy data for six industrial facilities were collected over multiple months in which production varied over these months. This technique then used a regression of monthly building energy or utilities' use versus monthly production rate. The nonprocess energy was estimated for each facility as the energy extrapolated to zero production in these regression models. The range of monthly production data was also used to determine a midpoint or average production at each facility and the corresponding average total building energy (process and nonprocess). The energy at zero production, as a percentage of the midpoint production energy, was thus the nonprocess energy percentage. In addition, the zero production power intensity (in watts per square meter) was compared to industry average nonprocess energy intensities (heating, cooling, lighting, and ventilation) to interpret the nature and possible improvement in nonprocess energy.