The Unilever case story

Unilever wanted to investigate several critical areas where the factory had the opportunity to reduce the power consumption of its existing pumps.

The pumps being used were 20 years old and were fitted with 37kW motors, running constantly with limited control of the motor. To control the flow, the discharge valve had been shut by almost 40%. It was agreed that in this instance the Grundfos Pump Audit tool should be used to undertake the assessment and was duly fitted to the sites 8” pipework in order to understand the process requirements downstream.

The subsequent report from the audit concluded that the existing 37kW pumps were costing more than £16k per annum to operate, once the correct duty had been calculated it was agreed that the replacement pumps would now only need to be rated at 15kW. This meant that a fixed speed replacement pump would have reduced costs to less than £7k per annum.

To further increase savings by 20%, Unilever opted to install Grundfos variable-speed pumps. The variable-speed solution has given Unilever greater control over the process, and the new pumps need only operate at a running speed of 45 Hz to supply the process. The payback period for the new pumps was a mere 12 months.