Sea Energy Conversion: Problems and Possibilities

Nowadays, policies are being developed in many countries in order to decrease their greenhouse gases emissions. While in this area some technologies are widely installed (wind and solar energy), other ones, like the sea energy, could get an important role in the medium and long term. That is why the most relevant technologies associated to the sea energy conversion are presented in this paper: Tidal energy (both the traditional power plants and those based on tidal streams), wave energy and ocean thermal energy conversion. However, the sea energy conversion is not completely developed yet due to some unsolved technical problems, apart from their high cost. The most important advantages and disadvantages related to each kind of technology are also analyzed in this paper, comparing the main characteristics among them. Therefore, technological development government policies and the possibility of setting up a related industrial field will be the key actions to make possible the future of the sea energy. Solving the economical and technical problems, it will be possible to make good use of this alternative source of energy, with high energy density.