Implementation of Energy Efficiency Strategies in Cooling Towers—A Techno-Economic Analysis

Abstract

This paper depicts the results of a detailed energy audit, analysis, and implementation of energy efficient operations and maintenance strategies in a large commercial mall in Kuwait. Initially, the cooling towers (CTs) operated only at high speed, and on a typical summer day, nearly one-fourth of the make-up water was used for self-cooling of air. The study based on measured data and analysis, for a period of one year, revealed that the use of variable frequency drive (VFD) could reduce the water wastage for self-cooling of air by as much as 75% and overall water consumption by 18.6% while keeping the cooling system performance at the design level. An optimization model was developed, suitable exclusively for arid climatic conditions. Implementation of various energy efficient operation and maintenance strategies (EEO&MS) with ventilation and air-conditioning (VAC), and lighting systems obtained an overall reduction of 9879 MWh/y, equivalent to a percentage reduction of 11.7% in the annual energy consumption and a 345 kW in peak power demand. The study estimated an economical benefit of 19,958 KD/y for the owners and to the Ministry of Electricity and Water, in addition to a considerable environmental benefit of deduction in CO2 emissions by 6990 t/y.