Tidal Fence TurbinesBY: FREDRICO WATSON

Table of Content Introduction What is a Tidal Fence Turbine? How does it work? Where are they placed?

United Kingdom Scotland Canada South Korea France

Advantages Disadvantages Conclusion

Introduction

Tidal energy has been around since 900 A.D. and has advance greatly over the years. The tidal fence turbine is a combination of a tidal barrage and tidal stream turbine. The tidal fence takes advantage of the fast flowing underwater currents and converts the kinetic energy into electricity.

What is a Tidal Fence Turbine? It is an man-made device used

to harvest kinetic energy from the sea

They are entwined together like a fence

They are submerged in the sea

How does it work? Tidal fence is a series mounted in a

row across a estuary Each turbine has a vertical shaft

attached The shaft is mounted in the fence The tidal currents spin the turbines When the turbine is turned the

attached generator shaft turns and produce electricity

The turbine and shaft are the only elements submerged

The generator and transformers are above water

Where are they placed? They are placed usually in enhanced tidal

areas By the entrance of estuaries or narrow

channels They are located in area such as The United

Kingdom, Scotland, Canada, South Korea & France

Water flow

United Kingdom

Estimated that the UK can generate 50.2 TW h/yr with tidal

Western Europe as a whole is estimated to generate up to 105TWh/yr

Tidal fences wouldn’t not affect the currents

Scotland The MeyGen tidal project is the largest

tidal turbine project in Caithness, Scotland The capacity proposed was 86MW They increased the capacity to 298MW The project was a collaboration of Atlantis

Resources & Morgan Stanley Atlantis Resources got full responsibility of

the project

Canada Installed a 20MW in Annapolis Basin The world third biggest operating tidal power plant Generates 50GWh annually Powers over 4000homes The plant is operated by Nova Scotia Power Uses a path built in the 1960’s Path meant to be a transportation link The plant has four single blade turbine The gates are closed when tides create head ponds Turbine generate power when the head pond is 1.6m or

more

South Korea The Sihwa Lake tidal power station has a

capacity of 254MW It is said to be world’s biggest tidal power

plant The plant uses 12.5km long seawall Has 10 submerged 25MW bulb turbines Project took 7years to be initiated &

operational Daewoo Engineering & Construction was

used for construction of the project The annual generation capacity of the

plant is 552.7GWh

France The La Rance tidal power plant has been

used since 1966 Was constructed in 1961 It is the world oldest power station The second biggest tidal power station The dam of the tidal plant is 145.1m long

with sixed wheel gates 163.6m long drain Power is produced using 24 reversible

10MW rated bulb turbines The power is sent to a 225kV national

transmission network The network powers approximately

130,000 household annually

Advantage

Energy can be produce all year round Can be calculated or predictable Clean energy Cheap energy after initial investment is paid off Can get more energy from waves compared to other renewables

such as wind

Disadvantages

Initial Cost Maintenance Can alter the flow of salt water in and out of bays Too many placed in an area can block the flow Kills marine life Limited locations to put them

Conclusion

Tidal energy is a very clean. It is a renewable and inexhaustible power source meaning that it can produce energy all year. It has the potential to replace coal. The only problem is that they cant be placed in any locations based on sea level restrictions. The high initial cost is also a set back to tidal plants. The tidal fence will be a great resource once problems such as the killing of marine life or altering currents are resolved.

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