Energy resources: Tidal energy
Energy from sources other than fossil or nuclear fuels is to a large extent free of the concerns about environmental effects and renewability that characterise those two sources. Each alternative source supplies energy continually, whether or not we use it. Many alternative sources of energy have been used in simple ways for millennia, e.g. wind and water mills, sails, wood burning - but only in the last two centuries has their potential begun to be exploited on an industrial scale. Except for geothermal energy, all have their origins in energy generated outside the Earth, yet the potential of each is limited by its total supply set against its rate of use. Each is likely to be renewable in the sense that the available rates of supply of each exceed those at which they are used. The main concern is whether or not such alternatives can supplant fossil- and nuclear-fuel use to power social needs fast enough to avoid the likelihood of future global warming and other kinds of pollution.
One of the alternative sources to consider is tidal energy.
The rise and fall of ocean tides result from the combined gravitational pull on water by the Moon and, to a lesser extent, by the Sun, which exerts a force on water directed towards the two astronomical bodies. These gravitational effects combine with centrifugalo forces that result from the Earth and the Moon orbiting each other to make the details of tidal changes complex.
This course considers the power of the ocean tides as a potential source of useable energy and whether or not they can ever make any significant contribution to global energy supplies.
This OpenLearn course provides a sample of level 2 study in