Typical efficiency by pump type, including the best-efficiency-point (BEP) value and part-load efficiency at 50% and 75% of BEP flow, plus the factors that drive efficiency. Use it to estimate absorbed power and energy cost, to compare pump families, and to understand the energy penalty of running a pump away from its best-efficiency point.
Energy is the dominant cost over a pump’s life — far larger than purchase and maintenance combined for any continuously-running unit — so efficiency is an economic decision, not just a technical one. A few points of efficiency, multiplied by thousands of running hours, pays back better materials, a correctly-sized motor and a variable-speed drive many times over.
Efficiency peaks at the best-efficiency point (BEP) and falls away on either side; running at 50–75% of BEP flow can cost ten points or more and also accelerates wear through recirculation and vibration. Larger pumps and higher specific speeds are inherently more efficient than small or very-high-head machines, and internal clearances widen with wear, so efficiency drifts down over time. The table below gives typical efficiency ranges and BEP and part-load values by pump type, with the main factors that drive them — use it to estimate absorbed power, compare options and judge the penalty of operating away from BEP.
Our expertise spans multiple industries with sector-specific water treatment solutions.
Explore closely-related tools, references and guides
Send your influent analysis and our engineers assess your process and recommend a tailored treatment solution — free, confidential and no obligation.
Select the regulatory standard for your country — it sets which parameters we need for a compliance-aware process assessment.
Required parameters for the chosen standard are flagged on the sample form. You can still submit a partial set and we will advise what else to test.
Your sample is stored against your company so we can track the project. Provide a company name or email as a minimum.