Pump ownership costs are much more than the initial cost of installation. Energy usage and maintenance costs can represent up to 95 per cent of pump costs over their life cycle.
Energy costs can be very significant, for example, pumps in municipal water systems can account for up to 50 per cent of the systems’ total energy usage.
Optimising pump performance to maximise efficiency can result in significant energy savings, lowering operational and maintenance costs. Optimising pump operation is also a significant tool in lowering an operation’s environmental footprint through minimising greenhouse gas emissions and improving sustainability.
The efficiency of a pumping system refers to the ratio of power used for useful work, compared to the amount of power consumed. While inefficiencies can also be introduced through friction in the pipeline, valves and other restrictions, common causes for poor pump efficiencies and high energy usage include:
- improper pump sizing, resulting in operating pumps away from their best efficiency point
- oversized or inefficient motors
- inefficient piping configuration
- throttling of valves to control flow rate
- frequent on/off pump cycling
- changing the function or capacity of a system without considering the effect on pumps
- poor maintenance leading to wear and damage to pump bearings, impellers, seals, motors and variable speed drives.
A pump efficiency assessment can identify these issues and develop strategies to optimise performance.