An energy recovery system includes a ventilation system of a defined area, at least one windmill located exterior to the defined area and at least one flow guide apparatus positioned between the at least one exhaust and the at least one windmill. The ventilation system has at least one exhaust from which air from within the defined area is expelled out of the defined area by an exhaust fan as an exhaust air flow. The one or more flow guide apparatuses are positioned between the exhaust and the one or more windmills and are preferably sized and configured to redirect at least a portion of the exhaust air flow into an axial flow that moves toward one or more of the windmills.