This study presents a comprehensive analysis of costs and benefits of technologies based on cold plasma for the removal of sulfur and nitrogen oxides of flue gases. Assessment is based on welfare economics and seeks to include all relevant costs and benefits to evaluate the net social benefit of a project. A plasma unit installed in a CHP plant was used as the case study for this study. Results obtained from the study showed that the use of plasma technology is not financially viable unless all economic, social and environmental costs and benefits for all parties affected by the project are included. Compared to alternative flue gas treatment technologies, plasma proved to be more economically attractive if capital expenditures and operating costs were taken into account.