Based on a further analysis for the case of fluorescent T5 lamp with electronic ballasts, it can be clearly observed that the real power for all case studies of fluorescent T5 lamp is significantly less than in comparison with the base case and its change has a value approximately 2 times less; this indicates that the energy saving will be improved by employing the fluorescent T5 lamp with electronic ballast and the end user or building can profit this advantage. However, by considering the %THDi, it can be seen that the obtained %THDi is significantly less than that of the.