Tides are basically big
bulges of water created by the gravity of the sun and the
moon. These bulges move around our planet, back and
forth, creating currents and causing water levels to rise
and drop. Since we know where the moon is at all times,
we can predict the rise or fall of water levels and at
which location it occurs. Usually it takes about twelve
hours for water to rise and twelve hours to fall.
We can take advantage of this
rise/fall phenomenon by harnessing renewable energy from
it. By installing barrages (small damns), we can generate
electricity from passing water by using turbines. Because
the rise/fall phenomenon is always there, tidal power is
a clean, non-polluting, renewable source of energy.
Check out the
disadvantages of tidal energy.