There are various methods which are commercially available for turbine air inlet cooling aiming to improve gas turbine efficiency. In this study a new approach has been proposed to improve performance of a gas turbine. The approach has been applied to one of the Khangiran refinery gas turbines. The idea is to cool inlet air of the gas turbine by potential cooling capacity of the refinery natural-gas pressure drop station. The study is part of a comprehensive program aimed to enhance gas turbines performance of the Khangiran gas refinery. The results show that the gas turbine inlet air temperature could be reduced in range of 4-25 K and the performance could be improved in range of 1.5-5% for almost 10 months. (C) 2009 Elsevier Ltd. All rights reserved.