Pumped Up

Steve Schofield offers strategies to optimise pump systems and identify energy savings

GIVEN the global rise in energy costs, there has never been a better time to review and assess the efficiency of your pumping systems – whatever their size, complexity or indeed sphere of operation.

In this article, I will offer guidance on purchasing, maintaining and designing pump systems for optimum energy efficiency, maximum CO2 reduction and best capital expenditure payback time.

Pump systems account for 20% of global electrical energy demand and between 25–50% of the electrical energy usage in certain applications. Pumps are the single largest user of electricity within industry across the EU, consuming over 300 TWh/y, which in turn accounts for over 65m t of CO2 emissions.

It is also well documented that rotodynamic pumps which account for 80% of the installed base are between 20-30% oversized. There is therefore a major potential to save energy if rotodynamic pumps are properly sized and operated.

Where to start: Assess the potential for savings

Understand your pumping system. To identify if a pumping system is sized correctly make the following checks:

• Are you wasting liquid flow?
• Are you creating additional pressure?
• What is the monitoring and controls philosophy?
• Are there any oversized pumps installed for your required duty?
• Are there any significantly old pumps employed in the system?
• Is there excessive noise in the system?
• Are there any throttling valves installed in the system?
• Have you the correct size of pipework installed?
• Inadequate maintenance lowers pump system efficiency, so what maintenance procedures are in place?
• Are you adopting a proactive equipment replacement programme to current EU legislation?