Electrical energy analysis of the University of Tennessee Lewisburg dairy Experiment Station

The primary objective of this study was to analyze the electrical consumption of the University ofTennessee Lewisburg Experiment Station and seven privately owned dairies in Tennessee. Extensive data were collected from the Lewisburg dairy, while limited data consisting of total electrical energy use were collected at the privately owned dairies. Electrical meters were installed at Lewisburg to separately measure the electrical energy use of: each of two vacuum pumps,each of two water heaters,each of two refrigeration compressors, and an air compressor. Weather data(temperatures)were also collected from the weather station at the Lewisburg Experiment Station. These data were used to see which parameters (milk production, number of cows being milked, and temperature) would best correlate to electrical consumption,as well as, create multiple regression prediction equations. Energy utilization indices (EUIs) were also calculated and compared to published energy utilization indices.

Results obtained from this study were used to create multiple regression models. These models found that the amount of milk produced was the major factor in predicting the electrical energy use for the vacuum pumps and refrigeration compressors. The monthly high temperature was found to also be an equally important factor influencing refrigeration energy use. The daily high temperature for each month were averaged and found to be the most important factor in predicting water heater energy use. Of all the parameters analyzed,the amount of milk produced was the most important in predicting overall energy use.

The energy utilization indices calculated for the Lewisburg diary ranged from well below to well above the reference indices. The energy utilization indices for the privately owned dairies ranged from slightly below to well above the reference indices.

Electrical components, such as, the vacuum pumps and air compressor may have some energy saving potential. The vacuum pumps should be operated independently,or a variable speed pump should be installed to save on electrical costs. The air compressor lines have regular leaks that should be repaired to minimize electrical use. Overall, the Lewisburg dairy was found to be typical in electrical energy use when compared to other dairy farms.