20141016IES_Pivot Low Pressure Drains_Usage Savings.docx

E1 = annual kWh savings per drain for replacing pivot low pressure drains
E2 = Estimated leaking flow rate per drain (4 gpm)
E3 = Average pump operating pressure (65 psi)
E4 = Average pumping plant efficiency (60% or 0.6)
E5 = Estimated average annual operating hours (1,940 hours)
Equation Constants
Conversion factor from psi to feet of head = 2.31
Conversion factor from hp to kW = 0.746
Units conversion factor for water horsepower calculation = 3,960