There is a need to quantify the environmental impact of powering macro base transmitter station sites with diesel generators. The energy consumption of diesel generators to power base stations for telecommunication networks is a contributor to global greenhouse gas (GHG) emissions. This paper presents a model for calculating emission generation. The model was used to study the environmental impact of macro radio base stations powered by diesel generators using the Hybrid Optimization Model for Electric Renewables (HOMER) - optimization and simulation software tool. The environmental impact of powering base stations with diesel generators was assessed by quantifying the emissions generated in terms of pollution and the impact in terms of environmental cost ($200t/yr). From the results of emissions generated from diesel generators and presented in this study [105.96 tonnes of carbon dioxide (CO2), 0.26 tonnes of carbon monoxide (CO), 0.03 tonnes of unburned hydrocarbons (UHC), 0.02 tonnes of particulate matter (PM), 0.21 tonnes of sulfur dioxide (SO2), and 2.33 tonnes of nitrogen oxides (NOX)], the use of diesel generators to power GSM base station sites is concluded to have significant environmental impact.