ENERGY PRODUCTION FROM SEA WAVES AND CURRENTS. A GENERAL REVIEW

Abstract

Energy from the sea constitutes the 'blue' type of the renewable energy sources (RES). During the last decades, a number of devices for electric energy production from sea waves and currents are in implementation. Depending on their location and the technologies, different types of those devices were developed. Concerning the highest mean wave power worldwide, this varies from 20 to 70 kW/m at the coasts of West Europe, Canada, USA, south coasts of Australia and Latin America. In the Mediterranean Sea the wave power varies between 4 and 11 kW/m. Regarding the the currents energy, the main exploitable type is the tidal currents mainly at West Europe and North America East coasts. Many countries of the afore-mentioned areas have exploited the energy from sea before the end of the previous millennium. Other countries, with low sea energy potential, are at the level of theoretical investigation. A special case of profitable exploitation of the 'marine' energy, especially when this energy potential is low, is the construction and operation of structures or devices which, apart from their main role (the protection of a harbour or desalination of the seawater), have also the additional role of the sea energy exploitation.