This Software for Design Activity in Power Plants Equipments helps the Power Plant engineers and managers to manage the development and design activities of equipments in the field of power plants. This paper is basically concerned with the computerization of the design activity of Condenser, vital equipment in Heat Exchanger Unit (HEU) of Thermal Power Plant required for condensing the steam and for further reclaimable purposes to achieve economy. This software will also provide facilities to maintain user profile and the respective work details. The study use a developed model which estimates software effort by studying and analyzing small and medium scale application software.