Theoretical investigations were conducted of pollutants dispersion, NOx, SO2 and Particulate Matter (PM), from stacks of arbitrary four power plants in Libya, e.g. North Benghazi, South Tripoli, Zweitina, Khoms. The first four stations are gas power plants, while the last one is gas and steam station. Gaussian plume model has been used to identify ground-level NOx concentrations profile downwind and crosswind of the chimneys through urban regions and also the location of maximum pollutant concentrations. The study is based on the worst-case emission conditions of Pasquill stability categories (class D). Results indicate that maximum ground-level NOx impacts for all plants locate at a distance of approximately 1.0-2.5 km from stacks. The site most critical to ambient air NOx impact is Zweitina, where the plant site is in direct vicinity to residential areas. Khoms electric station exhibits the maximum emitted NOx, SO2, and PM intensity, about 305, 48, and 0.7 mu g/m(3), respectively, that is lower than allowable concentrations recommended by World Health Organization. Copyright (c) 2006 John Wiley & Sons, Ltd.