Investigation of using blowdown of cooling tower to generate electricity

Abstract

This paper reports an investigation of using blowdown of cooling tower to generate electricity. To this end, a small model of an electric power system was designed and assembled. Three micro hydro turbine generators available in the market were tested at flowrate ranging from 300 to 2000 liter/hour similar to blowdown of cooling tower from power plant. The vertical head of water supplied to the turbines was varied 1, 1.5, and 2 m. Experimental data indicated that impulse turbine generator type can generate electricity at a maximum flowrate of 1000 liter/hour, with a power output of 1.05, 1.07, and 1.15 watts at head of 1, 1.5 and 2 m respectively. Pelton turbine can generate electricity at a maximum flowrate of 1300 liter/hour, with a power output of 10.11, 10.37, and 10.4 watts at head of 1, 1.5 and 2 m, respectively. Finally, water wheel turbine can generate electricity at a maximum flowrate of 2000 liter/hour, with a power output of 0.57, 0.68, and 0.83 watts at head of 1,1.5 and 2 m, respectively. Under test conditions, Pelton turbine is the most suitable to produce electricity following the proposed concept. The research output can be used as a guideline for using blowdown of cooling tower from power plants to produce electricity.