EVALUATION OF TURBINE SELECTION FOR ELECTRICITY GENERATION FROM COOLING TOWER BLOWDOWN WATER : A COMPARISON BETWEEN EXPERIMENTAL DATA OF A PELTON TURBINE AND REFERENCE DATA OF A KAPLAN TURBINE

Abstract

This research aims to evaluate the suitability of using water turbines to generate electricity from cooling tower blowdown water by comparing a Pelton turbine experimentally tested using a small-scale power generation prototype with a Kaplan turbine, analyzed using data from a Turbine Application Chart. A small-scale power generation prototype was constructed with dimensions of 0.70 meters in length, 3.68 meters in width, and 1.55 meters in height to test a 50-watt Pelton turbine under flow rates ranging from 500 to 1,300 liters per hour. The experiments were conducted under conditions simulating real cooling tower blowdown water flow and head. Voltage, current, and power output were measured at each flow rate. The results showed that under a flow rate of 25,590 liters per hour and a head of 2 meters, the Pelton turbine operated efficiently with cooling tower blowdown water when the flow rate was sufficiently high. Although the head was relatively low (2 meters), the system could still generate an appropriate amount of electricity for small loads. The Pelton turbine achieved a maximum power output of 321.02 watts, making it suitable for systems with high head and low flow rate. In contrast, the Kaplan turbine, which is designed for low head and high flow conditions, produced 125.37 watts. Using a Kaplan turbine may require system modifications to increase the flow rate. When comparing energy efficiency and installation feasibility, the Pelton turbine showed greater potential for application with cooling tower blowdown water. Additionally, it could reduce carbon dioxide emissions by approximately 1,686 kilograms per year.

            This study demonstrates that generating electricity from cooling tower blowdown using a small Pelton turbine is a feasible and promising approach. It offers an opportunity to recover energy from the cooling tower's discharge system, improve energy efficiency, and promote the use of renewable energy for long-term sustainability.