Seyed Ali Qasemi - Head of chemical engineering office in Montazer Ghaem Power plant
Abbas Khoshhal - Department of Chemical Engineering, Payame Noor University, Tehran, Iran
Alireza Poorhamidi - Energy Expert at National Standard organization of Iran

In this paper, a 156 MW conventional power plant is modelled by the help of Thermoflow software and the amount of water evaporation, drift and also blowdown of wet cooling tower is estimated and investigated to be optimized by the application various dry cooling systems. Possible substitutions of the existing wet cooling tower are: mechanical draft dry cooling system, natural draft dry cooling system, air cooled condenser, air cooled condenser with water spray and hybrid cooling system. Each of the mentioned substitutions is investigated in 4 probable project lives and also 3 various discount rates and economic aspect of each case is indicated by NPV, IRR and also payback period. This project seems mandatory to be employed out in order to reduce over 2.6 million m3 water waste per year of this power stataion.

Conventional power plant, Hybrid cooling system, Power de-rating,Water consumption, Mechanical draft dry cooling tower, Natural draft dry cooling system, Air cooled condenser