Question 1

Q.1. What do you mean by sustainable development?

Accepted Answer

Sustainable development is development that meets present energy and resource needs without compromising the ability of future generations to meet their own needs, balancing economic growth, environmental protection and social equity.

Question 2

Q.2. Define working principle of thermal power plant.

Accepted Answer

A thermal power plant converts the chemical energy of fuel into heat (by combustion), the heat converts water into high-pressure steam in a boiler, and the steam expands through a turbine coupled to an alternator, converting thermal energy into mechanical and then electrical energy.

Question 3

Q.3. What do you mean by fissile material?

Accepted Answer

A fissile material is an isotope capable of sustaining a nuclear fission chain reaction upon absorbing a slow (thermal) neutron, e.g., U-235, Pu-239 and U-233, which are used as nuclear reactor fuel.

Question 4

Q.4. What do you mean by solar desalination?

Accepted Answer

Solar desalination uses solar thermal energy to evaporate saline water and condense the vapor as fresh water, typically in a solar still, providing potable water in remote, sunny, water-scarce regions without electricity.

Question 5

Q.5. How many types of wind turbine are there? Name them.

Accepted Answer

Wind turbines are classified by axis orientation into two types: Horizontal Axis Wind Turbines (HAWT), where the rotor shaft is horizontal/parallel to the ground, and Vertical Axis Wind Turbines (VAWT), where the rotor shaft is vertical (e.g., Darrieus, Savonius types).

Question 6

Q.6. Define biomass energy.

Accepted Answer

Biomass energy is renewable energy derived from organic matter (plant and animal waste, wood, agricultural residue) through combustion, biochemical, or thermochemical conversion into heat, electricity, or biofuels.

Question 7

Q.7. Define energy farming.

Accepted Answer

Energy farming (or energy plantation) is the practice of cultivating fast-growing trees, shrubs and crops specifically for producing biomass fuel/energy, on wasteland or otherwise unused agricultural land.

Question 8

Q.8. Give concept of tidal energy.

Accepted Answer

Tidal energy harnesses the potential energy of rising and falling ocean tides (caused by gravitational pull of the moon and sun) by trapping water in a basin at high tide and releasing it through turbines at low tide to generate electricity.

Question 9

Q.9. What is geothermal energy?

Accepted Answer

Geothermal energy is the heat energy stored within the Earth's crust (from radioactive decay and residual heat from formation), extracted as steam or hot water from underground reservoirs to generate electricity or provide direct heating.

Question 10

Q.10. What is energy planning?

Accepted Answer

Energy planning is the systematic process of forecasting future energy demand and formulating strategies for exploration, development, allocation and utilization of various energy resources to meet that demand efficiently, economically and sustainably.

Question 11

Q.1. Discuss world energy status.

Accepted Answer

World energy status shows continued dominance of fossil fuels (~80% of primary energy: oil, coal, natural gas) despite rapid growth in renewables (solar, wind), with rising global demand driven by developing economies, alongside urgent decarbonization pressure due to climate change concerns.

Question 12

Q.2. Describe open cycle gas turbine plants.

Accepted Answer

An open-cycle gas turbine plant draws fresh atmospheric air, compresses it, burns fuel with it in a combustion chamber, expands the hot gases through a turbine to produce power, and exhausts the spent gases directly to the atmosphere rather than recirculating them.

Question 13

Q.3. Describe principle of operation of solar cookers.

Accepted Answer

A solar cooker operates on the principle of the greenhouse effect: sunlight passes through a transparent glass cover and is absorbed by a blackened cooking vessel, converting to heat that is trapped by the glass and insulated box, raising the temperature enough to cook food.

Question 14

Q.4. Describe principle of operation of solar dryers.

Accepted Answer

A solar dryer uses solar-heated air, circulated by natural or forced convection through a drying chamber, to remove moisture from agricultural produce, offering faster and more hygienic drying than open-sun drying.

Question 15

Q.5. Define wind energy conversion systems.

Accepted Answer

A Wind Energy Conversion System (WECS) is the complete assembly of equipment that captures the kinetic energy of moving air using rotor blades and converts it into mechanical shaft power, which a generator then converts into electrical energy.

Question 16

Q.6. What do you mean by pyrolysis?

Accepted Answer

Pyrolysis is the thermochemical decomposition of biomass at high temperature (300-900°C) in the complete or partial absence of oxygen, producing solid char, liquid bio-oil and combustible gases as products.

Question 17

Q.7. Describe wave energy.

Accepted Answer

Wave energy is the kinetic and potential energy contained in ocean surface waves, generated by wind blowing over the sea surface, harnessed by devices such as oscillating water columns, point absorbers and attenuators to generate electricity.

Question 18

Q.8. Describe geothermal energy.

Accepted Answer

Geothermal energy harnesses heat from within the Earth via hydrothermal reservoirs of steam or hot water tapped by wells, used directly for heating or to drive steam turbines (dry-steam, flash-steam, or binary-cycle plants) for electricity generation.

Question 19

Q.1. Discuss current energy scenario in India.

Accepted Answer

India's energy scenario is characterized by rapidly growing demand driven by economic growth and electrification, continued heavy reliance on coal (~70% of electricity generation) alongside oil and natural gas, but rapid, policy-driven expansion of renewable energy (solar, wind), with per-capita consumption still below the world average and significant thrust toward energy security, rural electrification and decarbonization (net-zero by 2070 target).

Question 20

Q.2. Describe basic schemes and working principles of thermal power plants wi…

Accepted Answer

A thermal power plant operates on the Rankine cycle, with major subsystems being the coal-and-ash handling circuit, air-and-flue-gas circuit, feed-water-and-steam circuit, and cooling-water circuit; feed water is boiled into superheated steam, expanded through the turbine to generate electricity, then condensed and recirculated.

Question 21

Q.3. Describe in detail closed cycle and open cycle gas turbine plants with s…

Accepted Answer

Gas turbine plants operate on the Brayton cycle; open-cycle plants draw fresh air, compress, combust and exhaust gases directly to atmosphere in one pass, while closed-cycle plants recirculate the same working fluid through a closed loop, using external heating and cooling via heat exchangers instead of direct combustion contact.

Question 22

Q.4. Explain in detail flat plate and concentrating solar collectors with sui…

Accepted Answer

Flat plate collectors use a blackened absorber plate under a glass cover to capture non-concentrated solar radiation for low-temperature applications (water/space heating up to ~80°C), while concentrating collectors use mirrors/lenses to focus sunlight onto a small receiver, achieving much higher temperatures for power generation and industrial process heat.

Question 23

Q.5. Describe in detail wind energy hybrid system.

Accepted Answer

A wind energy hybrid system combines wind turbines with one or more complementary sources (solar PV, diesel generator, battery storage, or micro-hydro) to provide reliable, continuous power despite the intermittent nature of wind alone, especially for remote/off-grid areas.

Question 24

Q.6. Describe biomass conversion technologies in detail.

Accepted Answer

Biomass conversion technologies include direct combustion, thermochemical routes (pyrolysis, gasification, liquefaction) and biochemical routes (anaerobic digestion, fermentation), each transforming raw biomass into heat, producer gas, bio-oil, biogas or liquid biofuels for energy use.

Question 25

Q.7. Write short notes on: (a) OTEC cycles (b) Solar pond

Accepted Answer

OTEC (Ocean Thermal Energy Conversion) generates power from the temperature difference between warm surface seawater and cold deep seawater using a Rankine-type cycle, while a solar pond is a body of saline water that stores absorbed solar heat in a stable, insulating bottom layer of concentrated brine, from which the heat can be extracted for power or heating.

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