Drinking water is the essential need for human beings, but most of the land mass is occupied by sea water which is salty in nature and contains lot of contaminants which must be purified in order for it to be consumable by living beings. There is huge scarcity for energy for purification of water and energy demands of human beings are ever increasing. In this scenario for day to day requirements energy is required for water purification, so powering a reverse osmosis system using renewable energy for producing fresh water is being considered as a viable option to meet such requirements. The techno economic evaluation of the small size reverse osmosis system has been presented in the following paper. All the renewable energies originate from Solar Energy, and the efficiency of Solar PV system is high when compared to other technologies, hence Solar PV technology in conjunction with reverse osmosis was considered the best option. In the present paper taking the climatic conditions of Bhopal in Central India, technical potential of such a project has been presented. HOMER software has been used to calculate the net present or Life cycle costs of the system and the comparison of all the costs has been presented. There is an additional advantage of using Renewable energy especially solar energy that the Carbon emissions can be reduced. Due to the increasing awareness among the countries to reduce the Carbon emissions, hence these technologies can earn carbon credits which are valuable assets for developing countries such as India. The results obtained clearly showed that even though the capital costs of a Solar PV system may be high but in the long run, it will give huge benefits. Due to the National Solar Mission, there is huge subsidies being provided for such systems, hence the entire future lies in harnessing these technologies.