Tidal Barrage

Question 1

How long is a tidal cycle?

Answer 1

12.5 hours

Question 2

When is the tidal range at its maximum?

Answer 2

When gravitational pull of the moon is augmented by the sun

Question 3

Describe how tidal barrage system works.

Answer 3

An area of coastal water, previously open to the sea is trapped by the construction of a barrage or a dam. Some gates allow free passage of water when required and others contain turbines for the production of electrical power as water flows down and through them.

Question 4

How much of the time is power actually produced?

Answer 4

Around 50% of the time. A system with a higher number of basins may overcome this though.

Question 5

What are the environmental impacts of tidal barrages?

Answer 5

At a local level, ecosystems have been known to collapse. Wildlife is effected and silt and pollutants can collect at the bottom of the basin. The interference with shipping can also be a problem.

Question 6

What is the equation describing the motion of a free surface?

Answer 6

dz/dt = CdA/Bsqrt2g(z1-z2)

Where A = cross sectional area, Cd = discharge coefficient, B = basin surface area.

Question 7

What is the equation for the power produced through tidal barrage energy capture?

Answer 7

P=rhogCdAsqrt(2g(z1-z2)^3)