AWWA JAW34226

Pumps that are operating efficiently look just like those that are wasting energy. It takes some work to identify which pumps are inefficient and why. The best approach depends on the size of the utility and its budget. Pump inefficiency can be addressed at several levels that range, in order of increasing cost, from field testing of equipment to the use of optimal computer control. Whatever steps are taken, conflicting goals must be met: everyday and emergency demands must be met; water quality must be maintained; and capital cost must be minimized. With this in mind, there are several causes of inefficiency. The author offers suggestions for solving various problems, from changing pressure-zone boundaries to avoiding peak-hour pumping. In addition to solving problems at hand, utilities can look at the bigger picture by analyzing their overall system, measuring wire-to water efficiency, or conducting an engineering-economic evaluation, which would include reviewing energy bills, identifying peak-demand periods, and determining operating points. Finally, optimization studies may provide added savings. Includes 7 references, figures.