Hydroelectric power plants use flowing water to produce electricity and are an efficient and environmentally friendly renewable energy source. They comprise a dam, reservoir, penstock, turbine, and generator. Hydroelectric power plants have advantages such as producing clean, renewable energy without emitting greenhouse gases, providing a stable and reliable source of electricity, and supporting aquatic ecosystems. However, they also face challenges such as environmental impact and limited availability of suitable sites. Careful planning and sustainable practices are necessary to ensure the long-term viability of hydroelectric power as a clean energy solution. Electrical Engineering Online shares the top 10 multiple-choice questions with a brief explanation on hydroelectric power plants.
Also see: Complete list of Electrical Engineering Online MCQ Questions
The energy source that is used to produce electricity in a hydropower plant
The energy source that is used to produce electricity in a hydro power plant
- Wind
- Solar
- Water
- Coal
Correct Answer: 3. Water
Explanation: The hydroelectric power station is the generating station that uses the potential energy of water for generation of electricity.
The major function of a dam in a hydro power plant is to
The major function of a dam in a hydro power plant is to
- Store water
- Generate steam
- Control pollution
- Prevent floods
Correct Answer: 1. Store water
Explanation: The dam in hydroelectric power station is a barrier that stores water and provides head to water. The basic construction and structure of dam varies area by area and topography of the site where it is construted.
The component of hydro power plant responsible for converting mechanical energy into electrical energy
The component of hydro power plant responsible for converting mechanical energy into electrical energy
- Turbine
- Transformer
- Condenser
- Generator
Correct Answer: 4. Generator
Explanation: The synchronous generator also sometimes identified as alternator is electrical part of hydroelectric power plant. Alternator is connected to turbine which is responsible for capturing energy of falling water. Once water hits the turbine blades, it rotates and causes the alternator to accordingly rotate.
The type of hydro power plant that does not require a DAM
The type of hydro power plant that does not require a DAM
- Run-of-river
- Pumped storage
- Tidal
- Reservoir
Correct Answer: Run-of-river
Explanation: Run-of-river type of hydroelectric power plant doesn’t requires a DAM. The term Run-of-river refers to a type of hydroelectric power plant that harnesses the natural flow of a river to generate electricity. Run of river hydro plants don’t need large-scale water storage or specially designed dams.
Which of the following is a major disadvantage of hydro power plants
Which of the following is a major disadvantage of hydro power plants
- High maintenance costs
- High capital costs
- Greenhouse gas emissions
- Unreliable source of energy
Correct Answer: 2. High capital costs
Explanation: One of the major offset associated with hydro power plants is high capital costs associated with it. The construction of dam and other relevant structures is quite expensive and results in raising the initial capital costs of plant.
Which of the following is a major advantage of hydro power plants
Which of the following is a major advantage of hydro power plants
- Low maintenance costs
- High capital costs
- Both of these
- None of these
Correct Answer: 1. Low maintenance costs
Explanation: One of the major advantages linked with hydro plants is maintenance costs. The construction of hydro power plant is quite simple as compared to nuclear, diesel and steam power plants and henceforth. Due to its comparable simpler design the maintenance charges are usually very small.
Which of the below mentioned is an environmental benefit of hydro power plants
Which of the below mentioned is an environmental benefit of hydro power plants
- Reduced air pollution
- Increased noise pollution
- Disruption of aquatic ecosystems
- Increased deforestation
Correct Answer: 1. Reduced air pollution
Explanation: Unlike coal power plants, the hydroelectric plant has no smoke or ash associated with it. As a result there are no environmental hazards in reference to air pollution.
The penstock in a hydro power plant is responsible for
The penstock in a hydro power plant is responsible for
- Storing water
- Regulating water flow
- Generating electricity
- Controlling dam operations
Correct Answer: 2. Regulating water flow
Explanation: Penstocks in hydro power plants are conduits that lead water to turbines. From given options, regulating water flow is the most appropriate option that indicates functionality of penstock. Hence 2. Regulating water flow is the correct answer.
The country which is the largest producer of hydroelectricity
The country which is the largest producer of hydroelectricity
- United States
- China
- India
- Germany
Correct Answer: 1. China
Explanation: China is the largest producer of hydroelectricity. With an installed hydropower capacity of 309 GW China is number 1 produced of hydropower. Next to China, is the Brazil which has total installed capacity of 109.4 GW followed by the USA which has installed capacity of 101.9 GW.
What is the efficiency range of a typical hydro power plants
What is the efficiency range of a typical hydro power plants
- 20-40%
- 40-60%
- 60-80%
- 80-90%
Correct Answer: 4. 80-90%
Explanation: Hydroelectric power plants are very efficient plants. The percentage efficiency of modern hydro power plants is as much high as about 80-90%.