Tidal power harnesses the energy of tides and converts it into electricity. Recent technological advancements have improved tidal power designs and turbine technologies, increasing the potential power available and lowering costs. Tidal power uses gravitational forces from the Moon and Sun that cause regular bulges in ocean water levels and currents. These tidal currents and changes in water levels can be captured by structures like dams or turbines to generate electricity.

2. TIDAL POWER
Tidal power, also called tidal energy, is a form of
hydropower that converts the energy of tides into
useful forms of power, mainly electricity. Many
recent technological developments and
improvements, both in design (e.g. dynamic tidal
power, tidal lagoons) and turbine technology (new
axial turbines, cross flow turbines), indicate that the
total availability of tidal power may be much higher
than previously assumed, and that economic and
environmental costs may be brought down to
competitive levels.

3. Tidal power is taken from the Earth's
oceanic tides; tidal forces are
periodic variations in gravitational
attraction exerted by celestial
bodies. These forces create
corresponding motions or currents in
the world's oceans. Due to the strong
attraction to the oceans, a bulge in
the water level is created, causing a
temporary increase in sea level.
When the sea level is raised, water
from the middle of the ocean is
forced to move toward the
shorelines, creating a tide. This
occurrence takes place in an
unfailing manner, due to the
consistent pattern of the moon’s
orbit around the earth. The
magnitude and character of this
motion reflects the changing
positions of the Moon and Sun
relative to the Earth, the effects of
Earth's rotation, and local geography
of the sea floor and coastlines.

4. Dynamic tidal power is an
untried but promising
technology that would
exploit an interaction
between potential and
kinetic energies in tidal
flows. It proposes that
very long dams be built
from coasts straight out
into the sea or ocean,
without enclosing an area.
Tidal phase differences are
introduced across the dam,
leading to a significant
water-level differential in
shallow coastal seas –
featuring strong coast-
parallel oscillating tidal
currents such as found in
the UK, China, and Korea.

5. Tidal Stream is the flow of water as the tide ebbs and floods, and
manifests itself as tidal current. Tidal Stream devices seek to
extract energy from this kinetic movement of water, much as
wind turbines extract energy from the movement of air.
The sea currents created by movement of the tides are often
magnified where water is forced to flow through narrow channels
or around headlands. There are a number of locations around the
coastline of the UK where the tidal stream resource is high, and it
is in these areas where early technology developments are taking
place to explore the prospect of harnessing tidal energy.
TIDAL STREAM

6. TIDAL RANGE
Tidal Range is the vertical
difference in height
between the high tide and
the succeeding low tide.
Artificial tidal barrages or
lagoons may be
constructed to capture the
tide. Turbines in the
barrier or lagoon generate
electricity as the tide
floods into the reservoir;
water thus retained can
then be released through
turbines, again generating
electricity once the tide
outside the barrier has
receded.

7. A tsunami also known as a seismic
sea wave or as a tidal wave, is a
series of waves in a body of water
caused by the displacement of a
large volume of water, generally in
an ocean or a large lake. In being
generated by the displacement of
water, a tsunami contrasts both
with a normal ocean wave
generated by wind and with tides,
which are generated by the
gravitational pull of the Moon and
the Sun on bodies of water. Tsunami
waves do not resemble normal sea
waves, because their wavelength is
far longer. Rather than appearing as
a breaking wave, a tsunami may
instead initially resemble a rapidly
rising tide, and for this reason they
are often referred to as tidal waves.
Tsunamis generally consist of a
series of waves with periods ranging
from minutes to hours, arriving in a
so-called "wave train"

8. A waterfall is a place where water flows over
a vertical drop in the course of a stream or
river. Waterfalls also occur where meltwater
drops over the edge of a tabular iceberg or
ice shelf. Waterfalls are commonly formed in
the upper course of the river.
Streams become wider and shallower just
above waterfalls due to flowing over the
rock shelf, and there is usually a deep area
just below the waterfall because of the
kinetic energy of the water hitting the
bottom. Waterfalls normally form in a rocky
area due to erosion. After a long period of
being fully formed, the water falling off the
ledge will retreat, causing a horizontal pit
parallel to the waterfall wall. Eventually, as
the pit grows deeper, the waterfall collapses
to be replaced by a steeply sloping stretch of
river bed. In addition to gradual processes
such as erosion, earth movement caused by
earthquakes or landslides or volcanoes can
cause a differential in land heights which
interfere with the natural course of a water
flow, and result in waterfalls.