Tidal Energy

Presented by: Courtney Winter and Quinn Foley

Overview*How Tidal Energy Works

*Environmental Impact

*Advantages/Disadvantages

*The Four Outputs

* Conclusion

Where Does Tidal Energy Come From?

Form of hydropower from the movement of water caused by tidal currents or the rise and fall of the sea levels due to the tides

Comes from waves that start from wind

This forms as a result of the sun's heating of the Earth

As the wind hits the water, ripples form which then push until they grow to be large waves

Relevant HistoryEight main sites around Britain where tidal

power stations could usefully be builtThe “Swan turbine” is a design that is

different to other devices. The blades are connected to an electrical generator without a gearbox in between.

The largest tidal power station in the world is in the Rance Estuary in northern France, in which it was built in 1966. Swan

turbine

The Process

Turbine and generator

Estuary

Produced in a motion that can be transformed into power

Channel or tube that flows the water

An efficient design that can be lifted on a ship for maintenance

Keeps the generator on the ocean floor

StatisticsA Tidal Reef across the Severn Estuary is

being proposed --- mud flats could still be exposed at low tide, and this

makes it to generate power for more hours in the tidal cycle

---can also make sections of it to allow shipping to go through, control tidal levels further upstream, prevent storm surges, and to avoid flooding on low-lying land

Tidal Reef across the

Severn Estuary

Statistics (continued)

Tide mills ---mill operated by the tidal movement of waterexamples:

Statistics (continued)Ebb and Flow (Flood and Drain)

---this invention relates to a system for a method of moving sea water by utilizing the tidal flow and ebb

Environmental ImpactMany birds rely on the tide uncovering the

mud flats so that they can feed

Tidal energy is a renewable source of electricity which does not result in the release of gases responsible for global warming or acid rain associated with fossil fuel generated electricity

Use of tidal energy could also decrease the need for nuclear power, with its associated radiation risks

AdvantagesTidal Power produces no fuel and produces

electricity reliably

It produces no greenhouse gases or other waste

Not expensive to maintain

Tides are predictable

Does not have a large environmental impact

DisadvantagesThere are few suitable sites for tidal

barrages

Only provides power for around 10 hours each day, when the tide is actually moving in or out

Damages like reduced flushing, winter icing and erosion can change the undergrowth of the area and disrupt the balance

Only is available in small regions

Four OutputsType 1- Expected and Desired

--- produces electricity reliablyType 2- Expected and Undesired

---can destroy marine life Type 3- Unexpected and Desired

---generator can make the sea level go down

Type 4- Unexpected and Undesired---(could possibly) put the generator in a

wrong place in which it would not generate electricity

Conclusion (and citations)Tidal Power is a good way to modernize our

energy systems and help improve our environment

Citations ---Darvill. 21 Dec. 2008 http://www.darvill.com.---Dictionary. 21 Dec. 2008 http://www.dictionary.com

.---How Stuff Works. 21 Dec. 2008

http://www.howstuffworks.com.

---Wikipedia. 21 Dec. 2008 http://www.wikipedia.com.

Questions?