moving to falling water in tides is known as tidal I grains. Tidal energy is harnessed for energy: electricity by constructing a dam across of opening to the sea. But this is not a majore of the following two (1) The rise and fall of sea water during is not enough to generate electricity of large scale, (2) There are very few sites which suitable for building tidal dams. thermal energy. (a) Ocean thermal energy : Water at the thace of an ocean gets heated by absorbing the remains cold. Thus, there is a difference in lants, levels of an ocean. This difference in temperature is found to be up to $20^{\circ }\mathrm{C}$. The energy available due to the difference in temperature of water at the surface and at deeper levels of ocean is called ocean thermal energy (OTE). Obviously, this energy also comes indirectly from the sun. Ocean thermal energy is harnessed for producing electricity by a device called ocean thermal energy conversion power plant (OTEC power plant). (b) Oceanic (or sea) waves energy : Due to the wind blowing on the surface of oceans, waves move at high speed on its surface which are called oceanic waves (or sea waves). Due to their high speed, they carry tremendous amount of energy with them. Thus, the kinotic energy 134