site is designed to be viewed on an
800 x 600 screen,
with level 4+
Created by Andy
Science teacher at
School, Weston-super-Mare, England
Web site http://www.darvill.clara.net/myon.htm
Wave Power - energy from the wind on the sea
Introduction How it
details Advantages Disadvantages Is it
Ocean waves are
caused by the wind as it blows across the sea. Waves are a powerful
source of energy.
The problem is
that it's not easy to harness this energy and convert it into
electricity in large amounts. Thus, wave power stations are
How it works
several methods of getting energy from waves, but one of the most
effective works like a swimming pool wave machine in reverse.
At a swimming
pool, air is blown in and out of a chamber beside the pool, which
makes the water outside bob up and down, causing waves.
At a wave power
station, the waves arriving cause the water in the chamber to rise
and fall, which means that air is forced in and out of the hole in
the top of the chamber.
We place a turbine
in this hole, which is turned by the air rushing in and out. The turbine
turns a generator.
A problem with this
design is that the rushing air can be very noisy, unless a silencer is
fitted to the turbine. The noise is not a huge problem anyway, as the
waves make quite a bit of noise themselves.
Once you've built
it, the energy is free, needs no fuel and produces no waste or
One big problem is
that of building and anchoring something that can withstand the roughest
conditions at sea, yet can generate a reasonable amount of power from
small waves. It's not much use if it only works during storms!
called Ocean Power Delivery are developing a method of
offshore wave energy collection, using a floating tube called
hinged tube (about the size of 5 railway carriages) bobs up and
down in the waves, as the hinges bend they pump hydraulic fluid
which drives generators.
more, including an interactive model, videos and technical details
company is called Renewable Energy Holdings. Their idea for
generating wave power (called "CETO") uses underwater
equipment on the sea bed near the coast. Waves passing across the
top of the unit make a piston move, which pumps seawater to drive
generators on land.
They're also involved with wind power and
more at http://www.reh-plc.com/projects_waveceto.asp
- The energy is
free - no fuel needed, no waste produced.
- Not expensive
to operate and maintain.
- Can produce a
great deal of energy.
- Depends on the
waves - sometimes you'll get loads of energy, sometimes nothing.
- Needs a suitable
site, where waves are consistently strong.
- Some designs are
- Must be able to
withstand very rough weather.
Is it renewable?
Wave power is renewable.