Energy savings in livestock houses through the use of variable speed fans

IAQ control is fundamental in livestock houses due to the presence of microbiological active contaminants that can affect the animal health. Furthermore, no mechanical cooling is present inside livestock houses and high ventilation flow rates (up to 50 ach) are provided to decrease the indoor air temperature during the warmest periods. On the one hand, ventilation represents a considerable energy consumption (up to 60% of the primary energy for climate control) and a financial cost for farmers. To decrease this energy consumption, one of the most promising solution are variable angular speed fans equipped with an Electronically Commutated (EC) motor. In this work, the effectiveness of this new type of fans is numerically assessed against the commonly used fixed (angular) speed fans. The numerical assessment is performed through a dynamic energy simulation model that was ad-hoc developed and validated for broiler houses. The results demonstrate that the new technology reduces both the electrical and the thermal energy consumption of the broiler house. In particular, the adoption of the variable speed fans entails a reduction in the energy use by about 20% if compared to a traditional ventilation system, maintaining the same indoor environmental conditions.