250+ TOP MCQs on Thermal and Hydropower and Answers

Irrigation Engineering Multiple Choice Questions on “Thermal and Hydropower”.

1. A hydropower plant developed at the site of a drop in an irrigation canal is of the type ________
a) runoff river plant
b) storage plant
c) pumped storage plant
d) tidal plant
Answer: a
Clarification: In the Run-off river installation, power is generated on the basis of day to day flow in the river. To maintain the water level at a pre-determined level, a weir or a barrage across the river is sometimes constructed. The excess water during the peak-off hours is temporarily stored on u/s side of the barrage.

2. A nuclear power development scheme is essentially a _____________________
a) thermal power scheme
b) hydropower scheme
c) both thermal and hydropower scheme
d) atomic power scheme
Answer: a
Clarification: Nuclear power station is the one where atomic fuel is used to produce steam. The steam is produced in water boilers in case of an ordinary thermal power station and in atomic power station, the boiler is replaced by a nuclear reactor and steam generator. This electric power generation scheme is called thermal power scheme.

3. Fossil fuels are used in _____________________
a) a nuclear power plant
b) an ordinary thermal power plant
c) a hydropower plant
d) atomic power plant
Answer: b
Clarification: Fossils fuels like coal, gas, oil, etc and atomic fuel are used to generate steam. Thermal power station or ordinary thermal power station is the one where the conventional type of fuels i.e. fossil fuels is used to produce steam for running the turbine.

4. A runoff river plant for hydropower generation is essentially a ________________________
a) high head scheme
b) medium head scheme
c) low head scheme
d) any of the schemes
Answer: c
Clarification: Run-off river plant is essentially a low head scheme. The plant installed on main rivers or on diversion canals is usually provided with small storage to meet the short term fluctuations of the water requirement of the plant.

5. A storage hydro plant essentially involves ________________
a) a barrage or a weir
b) a dam
c) either barrage or a dam
d) check dams
Answer: b
Clarification: A dam is constructed across the river and the powerhouse may be located at the foot of the dam. The powerhouse may sometimes be located much away from the dam at the end of the tunnels which carry water away from the reservoir.

6. The natural high waterfalls may be used for generation of ____________________
a) hydro-power
b) water-power
c) both hydropower and water power
d) thermal power
Answer: c
Clarification: Hydroelectricity can be generated from naturally existing waterfalls while most hydroelectric plants generate water from human-made waterfalls. The naturally available high falls can also be developed for generating electric power and the common examples are Jog falls in India and Niagara falls in the USA.

7. Which among the following is an example of a tidal plant?
a) Rance power station in France
b) Ganguwal powerhouse located on Nangal hydel channel in India
c) Sarda powerhouse located on Sarda canal in UP in India
d) Mohammad Pur and Pathri powerhouses on Ganga Canal
Answer: a
Clarification: The water that runs back to the ocean during low tides is also utilized to generate electric power and special turbines are provided for the same. Rance power station is an example of such tidal plants. The tidal range is about 11 meters and this powerhouse contains 9 units of 38,000 KW.

8. When the powerhouse is located near the dam as is done in the low head installations, it is known as _________________
a) concentrated fall hydroelectric development
b) divided fall hydroelectric development
c) concentrated fall thermal power development
d) divided fall thermal power development
Answer: a
Clarification: Divided fall development is the one where the water is carried to the powerhouse at a considerable distance from the dam through a canal. Concentrated fall hydroelectric development is the one when powerhouse is located near the dam as in low head installations.

9. Which of the following plants utilize the minimum flow in a river having no appreciable pondage on its upstream side?
a) Storage plant
b) Run-off river plant
c) Pumped storage plants
d) Tidal plants
Answer: b
Clarification: Run-off river plants utilize the minimum flow in a river having no appreciable pondage on its upstream side. The excess water is temporarily stored in the pond on u/s side when the discharge at the site is more than the demand i.e. peak-off hours. It is then utilized during peak hours.

10. Which among the following plant generates power during peak hours?
a) Storage plant
b) Run-off river plant
c) Pumped storage plants
d) Tidal plants
Answer: c
Clarification: During off-peak hours, the water is pumped back from the tailwater pool to the headwater pool for future use. The pumped storage plant is primarily meant for assisting an existing thermal plant or some hydel plant. They generate power during peak hours only.

11. Which of the following dam is not an example of High head scheme?
a) Bhakra dam in Punjab
b) Rihand dam In UP
c) Hoover Dam in the USA
d) Sarda canal
Answer: d
Clarification: This scheme uses a water head of more than 60 m or so. The common examples are Bhakra dam in Punjab, Rihand dam in UP and the Hoover Dam in the USA. Sarda powerhouse on Sarda canal is under low to the medium head scheme.

12. Pondage in a hydropower station is _________________________________
a) pond level
b) temporary storage to meet peak demands
c) excess runoff to last for years
d) excess runoff for a few hours only
Answer: b
Clarification: The pondage takes care of the hour to hour fluctuations over a day or occasionally day to day fluctuations over a weekly cycle. It ensures that the desired instantaneous rate of flow into the turbines under day to day changing conditions of power load as well as of inflow. It may also be provided for weekly demands.

13. In a low head scheme, a weir or barrage is constructed to raise the water level.
a) True
b) False
Answer: a
Clarification: A weir or a barrage is constructed to raise the level and the powerhouse is constructed either in the continuation or at some distance downstream of the barrage. The water is taken through an intake canal called the power canal or the diversion canal.

14. Which of the following plant uses a reversible turbine that can work at relatively high efficiencies and helps in reducing the cost of such a plant?
a) Run-off river plant
b) Storage plant
c) Pumped storage plant
d) Tidal plant
Answer: c
Clarification: Reversible turbine has been devised for heads varying between 15 to 90 m that can function both as a turbine as well as a pump. This provision helps considerably in improving the load factor of the power system. They can work at relatively high efficiencies and helps in cost reduction.