A manufacturer-published field result
Sulzer reports 15% lower electricity consumption following XFP pump installations in Sluis, Netherlands. This is the manufacturer’s application result, not a Prodso project reference or a savings promise for every facility. When reviewing a retrofit proposal, define the hydraulic service delivered and the energy used instead of applying another site’s percentage directly to your bill. The following measurement approach helps structure that assessment.
Keep a consistent measurement boundary
Record flow, total head, actual electrical input power and measurement duration on the comparison sheet. Nameplate kW is not the electrical power drawn at that moment. Results are not equivalent if one measurement includes only the motor and another includes controls and auxiliaries. With variable loads, compare representative operating periods rather than one instantaneous value. State the instruments, measurement positions and units clearly.
Illustrative calculation: wire-to-water efficiency
For an illustrative calculation unrelated to Sluis, assume water density of 1,000 kg/m³, flow of 50 m³/h and total head of 12 m. Hydraulic power, ρ × g × Q × H, is approximately 1.64 kW with Q converted to m³/s. At 3.0 kW electrical input, overall efficiency is about 54.5%. At 2.6 kW for the same hydraulic duty, it is about 62.9%. The difference is 8.4 percentage points; this is not motor efficiency.
Mechanical and operational scope of a retrofit
Fitting inside the wet well does not by itself establish suitability. Check connection geometry, lifting arrangements, service access, cable routing and existing protection. Operationally, redundancy, available capacity during maintenance and alarm responsibility also matter. To compare quotations on equal terms, request separate items for the pump, adaptation work, installation and commissioning. This makes differences in retrofit scope visible before an order is placed.
What evidence should support the purchase?
Keep baseline measurements, target operating range, acceptance method and annual operating hours together in the decision file. Maintenance labour and unplanned downtime can supplement the energy comparison, but unmeasured items should be identified as estimates. Manufacturer cases are useful starting points. The investment decision for your facility should rest on its own measurements, the quoted scope and a verifiable acceptance result.
Let’s select the right product.
Your contact information and a short description are enough to start. Add flow, head, fluid and quantity if known; we can clarify the rest together.