Environmental Engineering Reference
In-Depth Information
Moving water below
the ocean surface can
also generate power.
These underwater
streams are called
currents. Most move
much faster than the
tides that reach the shore.
One well-known current
is the Gulf Stream. It
carries warm water from
the Gulf of Mexico across
the North Atlantic Ocean.
Experts say that the
energy in this one large
current is equal to 30
times the energy created
by all the rivers on Earth.
No one has found a way
to tap this energy yet.
Some Florida researchers,
though, are testing
turbines off the coast of
their state. The constant
speed of the current—
5 miles (8 kilometers)
per hour—could one
day provide energy for
some of the large cities in
southern Florida.
u
Salter and
His “Duck”
British scientist Stephen Salter
was one of the fi rst modern
inventors to explore ways to
create electricity from ocean
waves. In 1974, he invented a new
device for capturing the energy
in waves. The device would sit on
the ocean surface and move up
and down as the waves passed
by. Inside the device, the energy
of the waves would move metal
rods called pistons. The rods
would power a generator that
created electricity. The shape
of Salter's device and the way it
moved reminded some people of
a duck. Salter wanted to set up
rows of his “ducks” to capture
the energy in the passing waves.
He ran out of money, however,
before he could test his device in
the ocean. Salter's Duck remains
too expensive to build on a large
scale, but Salter is still looking for
ways to use wave power.
