Improving the energy efficiency of pumping systems

Many pumping stations do not operate at anywhere near optimum energy effici ency. Work in the UK and overseas has consistently indicated that improving the operation and performance of pumping plant can make reductions in ener gy costs of between 30-50%. These savings may be generated by: refurbishing or replacing equipment that is worn or no longer appropriate f or the duty; improving the scheduling of multi-pump systems to give the minimum operatin g costs for any particular demand; employing appropriate technology such as high efficiency motors and efficie ncy enhancing coatings; more effectively matching pump performance to demand by improving pump sele ction, impeller trimming or the use of variable speed drives; minimising hydraulic losses and installation effects; continuous monitoring of high energy use pumping plant. Although several water companies are taking a proactive approach to the red uction of pumping costs there is still plenty of scope for improvement. Thi s paper draws on the experience of carrying out many pumping cost reduction programmes in the UK and overseas. It examines the methodology behind thes e programmes, details potential energy saving areas and gives real examples of where significant savings have been made.