Abstract
The dependence on fossil fuels for energy production has come to an alarming stage. Energy demand continues to increase with growing population. Consequently fossil fuel reserves are continuously draining and the world is confronted with their extinction in near future. This implied the use of non-conventional energy sources. Out of many such sources Tidal is the one which requires high amount of research. Tidal current technologies have salient advantages such as cleaner than fossil fuels, intermittent but predictable, security and diversity of supply, and limited social and environmental impacts. This paper presents the tidal stream turbines' working, types and some information about current and future power stations.