Question

Generally, _______a type turbine is used in a Tidal Power Plant.
1. Propeller
2. Reaction
3. Simple Impulse
4. Reversible

Answer 1

Correct Answer - Option 4 : Reversible

The turbine used in Tidal Power Plant:

• Turbines play the most important role in generating electricity. With the help of turbines, we can convert the kinetic energy of the ocean or tides into electricity. i.e., it is a renewable resource.
• Definition of a turbine is any rotary mechanical device that extracts energy from a flowing fluid.

Reaction Turbine

• A reaction turbine develops torque as a result of pressure or mass effects from the fluid it is in contact with.
• As a fluid passes through the turbine blades, it changes pressure and transfers some of that energy to the turbine.
• If the turbine is not fully immersed in the fluid, then it requires a casement to contain the fluid. Otherwise, the fluid would take the path of least resistance and bypass the turbine.
• Most steam turbines used in power generation, as well as wind turbines and most underwater turbines, are reaction types.

A reversible type turbine is used in a Tidal Power Plant.

Pelton Wheel Turbine

• Pelton Wheels work best in high pressure, low flow settings and worst in low pressure, high flow settings.
• Tides tend to be high flow, but relatively low pressure.
• So Pelton Wheels are not ideal for tidal power schemes that use stream generation.

Francis Turbine

• It is a reaction turbine, the Francis wheel requires a casement around its outside.
• When completely constructed a Francis turbine looks much like a Conch shell.
• Francis turbines are the most popular type of turbine used in hydroelectric plants where they range in size from 10 to 750 megawatts.
• They work well in heads from 10 to over 700 meters.

Kaplan Turbine

• A Kaplan turbine is beneficial in that it is able to operate in lower pressure situations where Pelton or Francis turbines cannot.
• Kaplan turbines operate well in head ranges of 10 to 70 meters.
• When modified with longer blades, similar to those found on wind turbines, Kaplan turbines do very well in tidal stream generator schemes where there is the low head, but high flow.
• Kaplan turbines are expensive to design and manufacture due to the fact that they are often custom-made for specific settings and applications.

Gorlov Turbine

• Simple design that is inexpensive to manufacture and has low maintenance needs
• It works well in low flow and low head settings.
• It is not dependent on the direction of current flow, so it works when the tide is coming and when it is going.