Abstract
As the ocean covers 70% of earth surface, it has a very significant role in providing the clean energy in the form of tidal energy, tidal currents, wave energy, temperature gradient and salinity gradient which are sufficient enough to meet the global energy demand. This paper presents an overview in respect of current state of research and development in the field of tidal energy as this form of renewable energy is considered as most advanced one. The article focuses on available technology to harness it, its estimated potential and its current exploitation level both globally as well as in India. Further, barriers and obstacles in its deployment and commercial exploitations have also been discussed.