Efficiency of pump equation Jul 19, 2024 · Demonstrates how pump curves are drawn showing TDH, pump head, power, efficiency, and NPSHR versus flow rate. 85 Power required = 2,060 kW. The work done by the pump to compress water (W pump) can be estimated from the enthalpy (H) change of water before entering (H 1) and after leaving (H 2) the pump. This equation can be used for ram pumps with diameter of With the help of these equations the head developed by a pump and the head utilised by a turbine can be easily determined. Isentropic efficiency of a pump is the same equation as a compressor. , from an underground water source to the top of a building). 25 WHP / 33 BHP). this section depicts curves for pump total head, efficiency, input power, and net positive suction head required (NPSHR) as a function of flow rate. Usually, temperature correction for water is negligible. B. 75 Power required = 2,340 kW Repeat with pump efficiency, E = 0. Calculate the power of the motor. An extension of the second equation also allows the computation of the BHP required at any point on a pump’s performance curve if we know its hydraulic efficiency. And finally, the efficiency of the pump must be known, this is usually obtained from the pump manufacturer's total heads vs. ρ. Flow Designation Q Unit m3/h Apr 1, 2021 · In this section (Equation 4), we assume that all of the input flow (Q) has exited the pump discharge nozzle (image 1). Actual Power required in pump can also be derived from Heat balance across the pump. It is also called wire-to-water efficiency as it calculates the power input to the motor in relation to the power output from the pump. Nov 5, 2020 · Centrifugal pumps can approach 94 percent efficiency, but typical efficiencies are 55 percent for small pumps and 70 percent for large pumps. If the motor supplies the pump with 12 hp, what is the efficiency of the pump? Jan 18, 2012 · Where: H bep = Head produced by the pump at BEP (feet) g = Gravitational constant (32. The formula for calculating the COP of a heat pump is: “` COP = Heat Transferred / Energy Consumed “` Types of COPs. As discussed before the refrigerator or heat pump efficiency is given by a parameter known as the coefficient of performance (COP). The absorbed pump power, also called shaft power, is given in kW and can be easily calculated using the following formula: P = (Q x H x SG) ÷ (ηx 3670) P = pump power kW. Dec 7, 2023 · Compute Pump Efficiency (η): Use the formula η=Phydraulic / BKW to determine pump efficiency. P s = the shaft power. Figure 4. We assume an ideal scenario where no heat is lost to the surroundings during OVERALL PUMP EFFICIENCY BASICS Overall Pump Efficiency is the relationship between power consumed and the rate of water delivery at a given pumping head. 5 P p = P w η p P p = P w η p A pump never operates on a single defined duty point alone. But for calculating the net suitable motor, you need to calculate the shaft power of the pump. 2. Difference in Heat flow Outlet and Heat flow inlet is the actual power required for the Now, we can calculate the efficiency of this centrifugal pump: Pump Efficiency = Water horsepower/mechanical horsepower = 8. 746 HP) Pump Motor Horsepower Motor HP = BHP / Motor Ef f Where • BHP = Break Horsepower Jan 20, 2025 · An exact calculation of the pump flow rate can ensure the understanding of the pump’s efficiency, reliability, and efficiency. This is denoted by “Qtotal”. , Ps is the power provided to the pump shaft in brake horsepower (BHP) and Pw is: May 19, 2022 · In this article provided pump related formulas like fluid flow rate and velocity, power calculation, Specific Speed of Pump (Nq), Total Head, Pump Torque and temperature rise, Net Positive Suction Head, Affinity laws for pump, Pump Efficiency & Overall Efficiency of the Pump. Flow rate (Q) = Pump speed x Impeller size x liquid density Pump efficiency is termed as the ratio of the power or energy imparted on the fluid by the pump in relation to the power supplied to drive the pump. Pump efficiency is the fluid power divided by the power input. Chart-1-Pump-Efficiency-for-flow-100-1000-GPM Loss and efficiency in positive displacement pump. P 2 and P 1 are measured with pressure gauges at the discharge and suction of the pump being assessed, Q is the total pump flow measured with a fixed or portable flow meter, and kW is the true power going to the electric motor driver. W pump = H 2 – H 1. Jun 22, 2021 · As a result of the pump efficiency calculations, it was determined that the efficiency of pump 3 on unit 2 is 53. Ascertain Total Head (H): The total head in a hydraulic system represents the height in feet that the pump needs to lift the water. η = overall efficiency. So, the Pump flow rate formula is. These formulas are common practice rules of thumb and provide theoretical values to which actual values will likely differ. Dec 16, 2024 · An electric motor has an efficiency of 35 %. The overall loss is also dependent upon the principle of construction and viscosity of the liquid. How to calculate pump efficiency? To calculate pump efficiency, you first need to determine the variables presented in the equation above. Pump displacement increases faster than pump slippage resulting in greater pump efficiency with increasing speed. Plug Values into the Equation: Insert your Q and H values into the WHP equation. The formula for calculating pump efficiency is: Jul 14, 2016 · Solving for the pump efficiency term, you arrive at the final pump efficiency equation (see Equation 6). Mar 4, 2012 · It describes how to measure key parameters like flow, head, and power to determine a pump's efficiency. Where: HR is the heating rate (amount of heat produced) W is the work (energy input The efficiency of a pump is a critical parameter that determines how effectively the pump converts electrical energy into hydraulic energy, ultimately influencing productivity and profitability across several industries. 95 and the efficiency from the manufacturer’s pump curve is 68 percent. Pump efficiency is the ratio of water power output to mechanical power input. The formula for calculating OPE is (Flow X Total Dynamic Head) divided by (HP-in X 3,960) Flow - GPM or rate in gallons per minute Whether calculating centrifugal pump efficiency, hydraulic pump performance, or heat pump efficiency, this tool provides precise efficiency assessments to optimize system performance and reduce energy costs. To determine specific efficiency for pump, motor and overall review the following equations: Example 1: A pump has a water horsepower requirement of 8. YouTube video tutorial at […] Pump efficiency (η) is also referred to as coupling or overall efficiency and characterises the ratio of pump power output (P Q) to power input (P) for the operating point in question: The best pump efficiency (η opt ) is the highest efficiency or the rotational speed and fluid handled as specified in the delivery contract. This involves analyzing factors such as the pump's design, operating conditions, and energy losses due to friction or other inefficiencies. Jul 19, 2024 · Pump input power can also be determined if the amount of power absorbed by the fluid and efficiency are known by rearranging the equation shown for the efficiency curve: Eq. W is the work needed by the considered approach. This involves assessing the ratio of hydraulic power output to the supplied shaft power, often expressed as a percentage. Heating COP (COPh): Measures the efficiency of the heat pump when operating in heating mode. The power output is equal to energy ÷ time Dec 3, 2023 · What is the formula for HP pump? If by “HP pump” you refer to Brake Horsepower (BHP) for a pump, the formula is PBKW =Q⋅H⋅ρ⋅g /η, where PBKW is the Brake Kilowatt power. 7 percent at that flow point. BHP is indicated on the pump performance curve as a function of pump capacity, and is used to select an appropriate size of motor (or other driver type) for the pump. Apr 29, 2024 · Pump Efficiency Formula Pump efficiency is a measure of how effectively a pump converts input power into useful output power. System without Static Head Because this system has no static head, Equation 1 was used to calculate the new operating pump speed: Because the new operating pump speed is less than 66. Aug 24, 2022 · Pump horsepower is an overview of a pump's capacity to achieve its rated discharge (or volumetric flow rate output) and pressure head. . It is Jul 19, 2024 · Pump input power can also be determined if the amount of power absorbed by the fluid and efficiency are known by rearranging the equation shown for the efficiency curve: Eq. 4 Pump efficiency considerations. Mathematically, mechanical efficiency formula is written as: The power at the impeller in kW. With the help of these equations the head developed by a pump and the head utilised by a turbine can be easily determined. The COP usually exceeds 1, especially in heat pumps, because instead of just converting work to heat (which, if 100% efficient, would be a COP of 1), it pumps additional heat from a heat source to where the heat is required. Aug 2, 2017 · It is calculated by (TDH x gpm x SG)/ (3960 x pump %). 6. Consequently, we need to think about how electrical power (when using electric motors) or heat power (when using combustion engines) converts into liquid power to really understand pump efficiency. In the U. Processing math: 0% Figure 4 to validate the mathematically calculated new pump efficiency. 25 water horsepower (WHP). In most cases, we use pumps to deliver water and other fluids to a higher location (e. 6 horsepower (hp) and in Equation 3, the pump efficiency (η) is calculated to be 55. P w = the water power. An air to air heat pump operates between temperature -5 o C on the cold side and temperature 40 o C on the hot side. AJ Design ☰ Math Geometry Physics Force Fluid Equation for water at 68 Fahrenheit Aug 1, 2023 · Equations For Heat Pump Efficiency. Centrifugal pump losses and efficiency are the sum of mechanical and hydraulic losses in the pump. 95. The first of which is the density of the fluid. As a rule of thumb - the temperature increase in a fan transporting air is approximately 1 o C. Equation 1 Efficiency. flow curve of the pump (see typical pump curve). So, in terms of kWh (or BTU output) the heat pump will use more than 3 times less kWh. For example, a pump that generates 1000 GPM at 100 Ft can also be said to be generating 25. The power at the shaft of the centrifugal pump is more than the power available at the impeller of the pump. The power equation calculates the power output of the wind mill based on the wind speed and turbine diameter. P s(kW) = shaft power (kW) η = pump efficiency. It indicates the ratio of the pump’s output power (often hydraulic power or water horsepower) to its input power (typically shaft power or brake horsepower). Jul 18, 2024 · The pump pressurizes liquid water from the condenser before it enters the boiler. In other contexts, the power input can also refer to the Brake Horse Power (BHP) or the actual power delivered by an engine. Maximum pump efficiency occurs at approximately Q* = 0. Thus, the hydraulic Feb 5, 2025 · For example, a system with lower efficiency requires a pump capable of delivering a higher head to compensate for the energy losses compared to a highly efficient system. The COP equation is: COP=\frac{Q}{W} Where: Q is the total heat supplied or removed by the system. Oct 1, 2023 · Pump efficiency is equal to the power of the water produced by the pump divided by the pump’s shaft power input. If the pump is powered by electricity derived from an open cycle gas turbine operating at 35% efficiency using methane, the CO2 emissions over a 20-year cycle would be 232,000 t with 75% pump efficiency and 205,000 t with 85% Centrifugal pump losses and efficiency. Which makes it a relatively poor design. Centrifugal pump efficiency equation. Pump efficiencies are certainly important to any well site or office personnel trying to run energy-efficient operations. Pump Efficiency Formula. Pump efficiency for developed head (F) between 50 and 300 ft and flow (G) between 100 and 1000 GPM is shown in Chart 1 below. 91 x 100 = 82%. Let’s use the example of 175 gpm at a TDH of 70. WHP = HQ 3960 Oct 3, 2024 · Pump efficiency is a critical measure in hydraulic systems, indicating how effectively a pump converts electrical power into hydraulic power. 5% (25. 5 P p = P w η p P p = P w η p • Efficiency = Pump efficiency from its pump curves for the water flow and TDH Power consumption, KWH = KW input x operating hours The KW input will depend on the motor efficiency and pump power requirement. Equation 4 . Do not compare this with the pump literature because the literature is for pump efficiency only. You can verify this by thinking about the range of possible efficiencies (0-100%). It’s expressed as a percentage. Continuity Equation: The continuity equation is simply a mathematical expression of the principle of conservation of mass. The overall efficiency of a centrifugal pump is simply the ratio of the water (output) power to the shaft (input) power and is illustrated by the equation below. The efficiency of a pump reflects its ability to move a fluid with minimal energy loss. The pump efficiency is 75%. The shaft power P supplied is defined as the product of rotary moments and angular velocity at the pump’s shaft coupling. S. Of course, you need to be aware that electricity per kWh (and per BTU) is more expensive than gas per kWh (or BTU). 4. Step by step example of calculation of pump power. Pump slippage increases with increasing pump speed. If the input horsepower into the pump is measured while the pump is generating 1000 GPM at 100 Ft, and the input horsepower is found to be 33 brake horsepower (BHP), the efficiency of the pump would be approximately 76. The flow rate of the pump directly depends upon the speed of the pump, impeller size, and density of fluid. 7. 3. The efficiency equation calculates the efficiency of the pump based on the pump size and fluid properties. Example: Calculate the Pump efficiency for the given details of horsepower . Feb 24, 2025 · Determining how effectively a pump converts input power into useful hydraulic power is essential for optimizing system performance and minimizing energy consumption. Loss and efficiency in positive displacement pump is determined by the appearance of losses as, internal leakage, internal friction, flow losses in inlet and outlet ports and mechanical losses. The efficiency can be increased slightly by using a diffuser. Calculate: Divide the product of Q and H by 3960 to find the water horsepower. Operators may want their pumping unit efficiency to be evaluated for the complete unit. CENTRIFUGAL PUMP SELECTION, SIZING, AND INTERPRETATION OF Dec 26, 2024 · The formula to calculate the heat pump efficiency (Ehp) is: Ehp = (HR / W) * 100. 39% and the efficiency of pumps 2, 4, and 7 is 63–72%. Efficiency is represented in percentages on the right side of the curve graph. A pump’s output power is determined by how much water and how much pressure it delivers. Pump efficiency, reflecting the pump’s internal energy conversion effectiveness, plays a significant role. A slippage formula called the Patterson equation is available to calculate the slippage volume and used to determine impact of slippage on pump efficiency and pump production. It is also called wire-to-water efficiency as it Mar 22, 2024 · To calculate the pump efficiency, multiply the density, gravitational constant, flow rate, and head together, then divide by the power input. Jan 20, 2012 · The overall efficiency of a centrifugal pump is simply the ratio of the water (output) power to the shaft (input) power and is illustrated by the equation below: Ef = PW / PS. Nov 9, 2024 · A higher COP indicates a more efficient heat pump. Flow can be measured using tracer methods, ultrasonic meters, or by filling a tank. As the name suggests these equations were formulated by Leonhard Euler in the eighteenth century. The SG of the fluid being pumped is 0. The pump efficiency is determined using the following formula: True pump system efficiency needs to factor in the efficiency of both the motor AND the pump. Jul 19, 2024 · Pump Curves Tutorial. However, most pumps do not operate at the peak efficiency, which is around 87 percent. The maximum theoretical efficiency can be calculated by using (1b) as. Thus, the hydraulic The shaft power - the power required transferred from the motor to the shaft of the pump - depends on the efficiency of the pump and can be calculated as. The more efficient the pump and motor, the lower the energy use. Step 1 : calculate the pump head Jul 28, 2015 · An empirical equation was presented to determine the efficiency of hydraulic ram pumps by using experimental data and nonlinear regression. Step 3: Calculate the power output. Measured Performance Data Note: This formula calculates both motor and pump-end efficiency as one total number. If so, the efficiency of the motor or engine will be included, and the overall efficiency will be lower than pump efficiency. At the BEP, Q = Q*, hp = hp*, BHP = BHP*. Namely, a 90% gas furnace has 90% efficiency; a 3 COP heat pump gas a 300% efficiency. Equation 5 from Jekat 2 approximates the hydraulic efficiency. A pump has to deliver 100 m3/h of water at 2 bar g and 20c, from a tank at atmospheric pressure. Water Power Output Pumps apply energy to develop the discharge pressure and deliver flow. However, is this a true assumption? Jun 26, 2023 · Calculating Overall Efficiency for Hydraulic Pumps. The amount of electrical energy used by the pumps in an average industrial facility will vary by plant type. Since the efficiency of electric motors is about 93%, it does not need to be changed. It lifts a 7. Answer: Step 1: Write down the efficiency equation (as a percentage) Step 2: Rearrange equation for the useful power in. Pump efficiency (E pump, Equation 1) is the ratio of the output work (called water power or water horsepower, WP) the pump exerts to the water in relation to Note: Equation for water at 68 Fahrenheit. 2 kg load through a height of 5 m in 3 s. Basic required formulas for the operation of Pump Pump efficiency is defined as the ratio of the hydraulic power imparted on the fluid to the electrical power input required to operate the pump. An inline water pump works between pressure 1 bar (1×10 5 N/m 2) and 10 bar (10× using this formula: It should be noted that this document outlines the procedures for determining pump efficiency only. Every pump exhibits internal losses while pumping. 02-hp pump input power (P) listed in Image 1. Formula: Pump efficiency is calculated using the equation: η = p × g × Q × H P × 100 \eta = \frac{p \times g \times Q \times H}{P Feb 24, 2024 · For example, if a pump has a volumetric efficiency of 90% and a mechanical/hydraulic efficiency of 91%, its overall efficiency is 82% (90 x 91 / 100 = 82%). Where: E f = efficiency. 3) Overall efficiency ( η o): Overall efficiency of a centrifugal pump is the ratio of the power output of the pump to the power input to the Oct 6, 2024 · A: The volumetric efficiency of a pump can be affected by several factors, including the design of the pump, the condition of the pump, and the operating conditions. Other equations for BHP can be written using other USCS or SI units, by taking Equations , and adding pump efficiency, η, in the denominator, as is done in Equation above. (1 KW = 0. Example Problem. 9% by dividing by the 98. COP heating = (40 + 273) / ((40 + 273) - (-5 + 273)) = 6. May 22, 2022 · Using the flow and head for the supply pump in Image 1, the calculations show the pump output power to be 54. 9 x 0. P s(kW) = P h(kW) / η (3) where . The efficiency points are then plotted on the graph and the curve is generated (below figure). Depending on variations on the TDH and flow discharge the pump efficiency may be lower than the peak. Centrifugal Pump Efficiency and Discharge Temperature. Sep 3, 2020 · To make it easier, I made two charts to represent Equation 1 and Equation 2, respectively. The difference between these two measurements is taken and the 2nd formula above is used to convert to head. Overall efficiency for a hydraulic pump is simply the product of volumetric and mechanical/hydraulic efficiency. Q: How can volumetric efficiency be improved? A: Volumetric efficiency can be improved by using a pump that is properly designed for the application, maintaining the pump in good Sep 11, 2017 · In this article we learn how to perform pump calculations in both imperial and metric units to assess pumping performance following the change of flow rate, pump speed, head pressure and power. [1] These equations can be derived from the moment of momentum equation when applied for a pump or a turbine. Calculating pump efficiency Pump efficiency: Here: • Q is the flow in cubic meters per hour (m3/h) • H is the pump head, or pressure, in meters (m) • P 1 is the motor power consumption in kilowatts (kW) Note: This formula calculates both motor and pump-end efficiency as one total number. For example, a pump receiving 10 kW of shaft power and delivering 8 kW of hydraulic power operates at 80% The overall efficiency of a centrifugal pump is simply the ratio of the water (output) power to the shaft (input) power and is illustrated by the equation below. 7%, Equation 4 was used to calculate the pump efficiency operating at point B. The typical practical value for a heat pump is in the The Pump Volumetric Efficiency equation calculates a pump's Volumetric Efficiency (Effvol) in percent (%) given it's Actual Flow Rate Output (Qact) and Theoretical Flow Rate Output (Qtheo). There are two main types of COPs for heat pumps: 1. In the ‘traditional’ technique, pump efficiency is calculated from equation (1) as follows: η = q. Takaishi, Tatsuo; Numata, Akira; Nakano, Ryouji; Sakaguchi, Katsuhiko (March 2008). The shaft power is equal to the pump required power divided by the efficiency. 2 ft/sec2) ηH = Hydraulic efficiency, as a decimal. For a pump, the efficiency equation is, A pump's differential head (in feet) is calculated from suction and discharge pressures as, Mar 12, 2025 · The heat pump equation used to calculate the efficiency of a heat pump system is the Coefficient of Performance (COP) formula, which is the ratio of the heat output to the work input. For example, a pump that uses 10 kW of electricity to deliver 8 kW of hydraulic power has an 80% effectiveness rating. Formula for Calculating COP. So essentially, it is the ideal "work" required by the pump for a reversible cycle (numerator) divided by the actual work required by the pump (denominator). Volumetric Efficiency. P W The thermal efficiency of such a simple Rankine cycle and in terms of specific enthalpies would be: It is a very simple equation, and for the determination of the thermal efficiency, you can use data from steam tables. The formula for calculating pump efficiency is: Efficiency = (Flow Rate x Total Head x Specific Weight of Liquid) / (3960 x Brake Horsepower) Higher efficiency means less energy waste. The formula for efficiency is as follows: Using the above formula, the efficiency at which the pump is operating at any given capacity can be determined. Example - Hydraulic Efficiency for a Pump. With the rising demand for energy efficiency and sustainability, particularly in sectors such as manufacturing, agriculture, and water management, optimizing pump efficiency Pump calculator solving for efficiency given water and brake horsepower. The affinity laws for pumps express the relationship between the several variables involved in pump performance. The pump is connected to a pipe of same diameter DN100 at the inlet and outlet of the pump. g. This is the best efficiency point BEP. It includes both elevation difference and friction losses. Jun 12, 2022 · The pump efficiency curve describes a pump’s efficiency over its whole operating range. References of pump efficiency : depending on the pump design and the pump speed, the typical pump efficiency will be 80-90% for a single stage pump and 70-90% for multi stage high pressure pumps. Aug 25, 2006 · To calculate the efficiency of different parallel pumps, or identical parallel pumps with different differential head outputs, I would use a weighted average of the sum of the individual efficiencies. Solve for pump efficiency: Solve for brake horsepower: Net on seat. H/ M E. This formula accounts for the actual power used by the pump, considering its efficiency. The efficiency curve’s peak characterizes the BEP, with efficiency diminishing as the curve arcs away, either right or left, from the BEP. At any other operating point, efficiency is less, pump head can be higher or lower, and BHP can be higher or lower. Understanding Example - Maximum Heat Pump Efficiency. Then the pump will work in the area with the best efficiency. Online Pump Calculator - SI-units Note: This formula calculates both motor and pump-end efficiency as one total number. For this reason, care should be taken in dimensioning that the heat pump’s duty point is in the middle third of the pump curve for most of the heating period. The losses in a pump or fan converts to heat that is transferred to the fluid and the surroundings. η = P W / P S where η is efficiency, P w is the water power, and P s is the shaft power. Defining Pump Efficiency. Jan 20, 2012 · These equations predict that a pump that produces 100 GPM at 30 feet of head and requires 1 BHP will have an overall efficiency is 75. Several factors influence system efficiency. In Equation 4, we assumed that all the flow that enters the pump also exits from it. A part of the shaft power is used in overcoming friction resistance in bearings and The equations for a wind mill powered piston pump include the power equation, the efficiency equation, and the flow rate equation. The Pump Volumetric Efficiency equation calculates a pump's Volumetric Efficiency (Effvol) in percent (%) given it's Actual Flow Rate Output (Qact) and Theoretical Flow Rate Output (Qtheo). That’s It. The efficiency cannot be measured directly, but must be calculated from the measured information. Jul 28, 2015 · An empirical equation was presented to determine the efficiency of hydraulic ram pumps by using experimental data and nonlinear regression. Dec 31, 2019 · For this, 226 commercial pumps were studied, registering the efficiency at the optimum operating point, as well as other variables such as the flow rate, height, and pump type. Overall efficiency is the most important measure of the performance of a pump or motor. So in other words, Qinlet = Qoutlet. A pump performance curve is a graphical representation of the head generated by a specific pump model at rates of flow from zero to maximum at a given operating speed. This ratio expresses how effectively the pump converts input power to useful hydraulic power. Efficiency can be determined with the following equation: The equation above is for general pump efficiency. 84/20 * 100 = 44% In this hypothetical example, our centrifugal pump has a peak efficiency of 44%. There are numerous inefficiencies inherent in converting energy to usable fluid power, some of which are entirely pump design issues (and hence not readily changeable once the pump purchase is made). Efficiency of Pump. P (kW -Shaft) = P (kW) / η. Total head is the difference between suction and discharge heads. Dec 14, 2023 · Pump efficiency, E = 0. 6 Qmax. The continuity equation is: m (inlet) = m (outlet) (ρ 1 x A 1 x v 1) inlet = (ρ 2 x A 2 x v 2) outlet (ρ 1 2x (R 1) x v 1) inlet = (ρ 2 2x (R 2) x v 2) outlet Example 8: Mar 1, 2025 · Determining how effectively a pump converts input power into useful hydraulic output is crucial in various applications. Hence the required motor power in kW formula can be written as, P (kW -motor) = q (m 3 /hr) x ρ (kg/m 3) x g (m 2 /s) x h (m) x p (Pa On-site constraints often make it difficult to accurately measure pump efficiency under installed conditions by the same method that pump manufacturers traditionally use for works tests. Heat Pump Efficiency: Types and Equations Different Types of Pumps: Ultimate Guide in 2021 Determining Pump Efficiency As mentioned before, pump efficiency can be calculated by dividing the water (P ) power by the shaft power (P). 1. This equation can be used for ram pumps with diameter of The difference between these two measurements is taken and the 2nd formula above is used to convert to head. So continuing with the above example, the overall efficiency of the pump is 0. Centrifugal pump efficiency = Power Output from Pump/ Power Input to Pump * 100. 5 whp. svnohq dzsmuna huoeh lba agputkx xsyhu umpjekey ixlne fytjorjm asooyf gyb witavok ajp knehs gbtmg