Ocean
Power
Ocean Power
Tidal and Wave energy
Boyd Evans
Tabitha Darko
Diana Crow
Many Ways to Harness
Ocean Power
There are several ways to harness the
power of the ocean. The main Goal Remains
the Same for each technique, to harness the
immense wave power in the world’s oceans.
The technology we develop to do this may
someday be used to solve the world’s energy
crisis, and make human life more
sustainable.
Wave Energy: Duck Buoys
• Rising and falling of
buoys on the ocean
generates mechanical
energy
• Mechanical energy
converted into electric
energy
• Sends electricity to
shore through
underwater power cable
http://www.oceanpowertechnologies.com/tech.htm#
Pros and Con of Wave Buoys
– Pros
• Simple installation
• No emissions or wastewater
• A 10-megawatt station
would only take up 30
acres of ocean
• 1000x Higher Energy
density than wind
• Not disruptive
• Can help wildlife by acting
as artificial reef
– Con
• Wave buoys are
very easily
damaged in
storms
Wave Energy
• Ocean waves are caused by the wind as it
blows across the open expanse
• of water, the gravitational pull from the sun
and moon, and changes in atmospheric
pressure, earthquakes and other things.
• Waves created by the wind are the most
common waves and the waves relevant for
most wave energy technology.
Wave Power (Continued)
• Wave energy conversion takes advantage of
the ocean waves caused primarily by the
interaction of winds with the ocean surface.
• They are a powerful source of energy, but are
difficult to harness and convert into
electricity in large quantities.
Tech Obstacles
• The energy needs to be converted to a 60
Hertz frequency before it can be added to the
electric utility grid.
• The majority of designs to capture wave
power call for many small units, each
having their own turbine. This results in a
high voltage, but frequency substantially
lower than 60 Hertz. However, it can be
converted via several adaptors in the plant
Wave Hub: Large Wave Farm in
planning stages
• Could create 1,800 jobs and
over 500 million pounds
• Enough electricity for
7,500 homes
• Save 300,000 tons of
carbon dioxide
• 15% of energy for
Southwest England
http://www.wavehub.co.uk/
• From just ONE wave farm
• Just a 4x2 km area
So far most of the Ocean’s energy has
gone untapped despite the fact that it has
No emissions
Minimal environmental
disruption
Huge amount of energy
Unlike wind and solar power, the tides are
always in motion.
F.Y.I.
The moon’s gravity
acting on the ocean’s
water and the Earth’s
centrifugal force cause
the tides to go in and out
every day. In essence,
this makes tidal power
kinda like lunar power,
as opposed to solar power
http://www.unm.edu/~abqtom/images/Moon/Moon11-19-02b.jpg
Ocean Current
• Turbine acts as an
underwater windmill to
ocean currents
www.wikipedia.org/tidalpower open source
Pros /Cons for Ocean Current
– Pros
• Very high energy yield
per turbine
– Cons
• Needs currents with
speed of 4.5 to 5 knots
or higher
• Needs depth of 20-30m
• Not every coast meets
those requirements
• Some models can be
noisy
Tidal Power
• This technique takes advantage of the rise
and fall of the tides to produce electric power
in a design similar to that of a dam that you
would find in an artificial lake
• There Are several techniques for achieving
this subcategory as well.
Channelization
Channelization
Turbine
Narrow
Channel
Backto the Ocean
Tidal Dams
Political / Economic obstacles of Ocean Power
• costly to develop and put together
• could interfere with mooring and anchorage lines
with commercial and sport-fishing
• Long term problem is making the technology work
at a cost of power which a consumer is willing to
pay
• Some Slight Negative Environmental Impacts
• can disturb or disrupt marine life
• may degrade scenic ocean front views from wave
energy devices located near or on the shore
Make a Difference
• The energy from waves alone could supply
the world's electricity needs.
• The total power of waves breaking on the
world's coastlines is estimated at 2 to
• 3 million megawatts.
• Does not create pollution by releasing carbon
dioxide.
• Wave energy is free after cost to build plants
• Maintenance / operation costs are very low
Bibliography
• http://www.southwestrda.org.uk/news/release.asp?releaseid
=2136
• http://www.marineturbines.com/background.htm
• http://home.hiwaay.net/~krcool/Astro/moon/moontides/
• http://www.oceanpowertechnologies.com/tech.html
• http://www.wavesenergy.com
• http://www.jamstec.go.jp/jamstec/MTD/Whale/
• Snedden, Robert. Energy Alternatives
• Chicago, Illinois. Reed
• Educational and Professional Publishing. 2002. p. 28