Tidal Turbines

5 September 2007

Stephen was inspired to design and make this TIDAL TURBINE model by the Behind the News wind farm story and rain water tank project.
Stephen watches Behind the News with his class mates at St Francis Xavier's Catholic School.

My project is looking at an efficient way to create green electricity using the power of the waves and tide.

The structure of the water turbines is similar to that of a weir. Inside there will be separate compartments. The number of compartments will be determined by the size of the whole project. The size of the structure will determine on the location and the ebb and flow of the tide.

Inside the compartments are large turbines which are pushed by the current coming through holes near the top of each one. The water will then be pushed out of a hole through the back of each compartment, or a hole positioned at the front of the base of each compartment.

When water is pushed out through the hole at the base, it is pushed into the oncoming current which will then be pushed back through the top hole, causing the process to continually repeat itself. When the water travels through the hole at the back of each compartment, it will continue on its journey to the coast.

Inside each turbine on the ends are magnets, so when spinning they turn around a metal shaft creating an electrical impulse, this will be using water proof wiring running along the ocean floor, to a rectifier onshore which will clean and regulate the incoming impulses to alternating current.

When the tide is going, out the water will enter through the rear hole of each compartment and turn the turbines then being forced out the top hole where it will continue its journey.

Costs and maintenance could be reduced by building the unit on submersible pontoon allowing the structure to be retrieved or relocated as required. Water proof cabling can run out from the turbines to a shore based rectifier.

Most of the project will be made out fibre glass to prevent and reduce the amount of corrosion and to stop sea life inhabiting the structure. The turbines acts as a self cleaning force, the sea life will slip off and lose grip for the speed and force of the turbines themselves, which are made out of fibre glass will push them off. The outside structure though, will need to be scraped regularly of molluscs and other sea life.

My idea could power all coastal cities and could be converted to inland cities while other reusable energy sources could power populations out of reach of this.


by Stephen Comley


If you want to know more about tidal power check out these sites:
• Tidal Energy Systems
• Tidal Power
• Tidal Turbine Images