D40 QUIZ OF THE DAY

What is the function of a surge tank in a hydroelectric project?

• To increase water velocity
• To reduce water hammer pressure
• To store energy
• To purify water

Answer explanation

Surge tanks are provided to absorb water hammer pressure caused by load fluctuations in penstocks.

Which turbine is best suited for high head and low discharge?

• Francis turbine
• Kaplan turbine
• Pelton turbine
• Propeller turbine

Answer explanation

Pelton turbines are impulse turbines designed for high head and low flow rates.

Which part conveys water from the reservoir to the power house?

• Draft tube
• Penstock
• Forebay
• Spillway

Answer explanation

Penstock carries water under pressure from the forebay to the turbine.

What type of energy conversion takes place in the turbine of a hydroelectric power plant?

• Mechanical to Electrical
• Hydraulic to Mechanical
• Thermal to Mechanical
• Hydraulic to Thermal

Answer explanation

Turbine converts hydraulic energy to mechanical energy, which is then converted to electricity.

Which of the following is NOT an impulse turbine?

• Pelton
• Turgo
• Kaplan
• Crossflow

Answer explanation

Kaplan is a reaction turbine, not an impulse turbine.

If the gross head is 100 m and net head is 80 m, what is the hydraulic efficiency?

• 80%
• 100%
• 60%
• 20%

Answer explanation

Hydraulic efficiency = Net Head / Gross Head = 80/100 = 0.8 or 80%.

A plant has a turbine efficiency of 90% and generator efficiency of 95%. What is the overall plant efficiency?

• 85.5%
• 90%
• 95%
• 80%

Answer explanation

Overall efficiency = 0.90 × 0.95 = 0.855 or 85.5%.

Which component connects the turbine to the tailrace and increases fluid pressure?

• Forebay
• Penstock
• Draft Tube
• Surge Tank

Answer explanation

Draft tube is a diverging tube provided at the exit of runner to recover pressure head.

Which turbine is suitable for low head and high discharge?

• Pelton
• Turgo
• Francis
• Kaplan

Answer explanation

Kaplan turbines are axial flow reaction turbines used for low head, high discharge.

What does the capacity factor of a hydroelectric plant represent?

• Installed capacity only
• Ratio of actual to maximum potential energy

• Overall efficiency
• Head loss

Answer explanation

Capacity factor = actual energy produced / maximum potential energy.