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PG Diploma Solar Semester one Paper 2 Exam Section B
- April 4, 2026
- Posted by: iisemumbai
- Category: Question bank
PG Diploma Solar Semester one Paper 2 Exam Section B
🔹 Renewable Energy (Q1–Q12)
1. What is energy?
Answer: Energy is the capacity to do work or perform tasks. It exists in different forms such as electrical, thermal, and mechanical energy. It is essential for all human activities and development processes.
2. State the first law of thermodynamics.
Answer: The first law states that energy cannot be created or destroyed. It can only be converted from one form to another. This principle applies to all energy systems, including solar energy systems.
3. What are renewable energy sources?
Answer: Renewable energy sources are those that are naturally replenished over time. Examples include solar, wind, and biomass energy. They are sustainable and environmentally friendly.
4. Give two examples of renewable energy.
Answer: Solar energy and wind energy are common examples of renewable energy. They are widely used for electricity generation. These sources do not get depleted easily.
5. What are conventional energy sources?
Answer: Conventional energy sources are traditional sources like coal, petroleum, and natural gas. They are limited in supply and cause environmental pollution. These are also called non-renewable sources.
6. Why is renewable energy important?
Answer: Renewable energy is important because it reduces dependence on fossil fuels. It helps lower greenhouse gas emissions and supports sustainable development. It also ensures long-term energy availability.
7. What is solar energy?
Answer: Solar energy is the energy obtained from the sun’s radiation. It can be converted into electricity using solar panels. It is clean, abundant, and widely available.
8. What is biomass energy?
Answer: Biomass energy is derived from organic materials such as plant waste and animal matter. It can be used to produce heat and electricity. It is considered a renewable energy source.
9. What is wind energy?
Answer: Wind energy is produced using the movement of air. Wind turbines convert kinetic energy into electrical energy. It is a clean and renewable source of power.
10. Why is electrical energy convenient?
Answer: Electrical energy is easy to transmit over long distances. It can be converted into other forms like heat and light. It is widely used in homes, industries, and transportation.
11. What is COâ‚‚ emission?
Answer: COâ‚‚ emission refers to the release of carbon dioxide gas into the atmosphere. It mainly occurs due to burning fossil fuels. High COâ‚‚ levels contribute to global warming.
12. How does renewable energy help the environment?
Answer: Renewable energy reduces air pollution and greenhouse gas emissions. It minimizes environmental damage compared to fossil fuels. It supports cleaner and greener energy production.
🔹 Basics of Electricity (Q13–Q30)
13. What is electric current?
Answer: Electric current is the flow of electrons through a conductor. It occurs when a voltage is applied across a circuit. It is measured in amperes.
14. What is voltage?
Answer: Voltage is the force that pushes electrons through a conductor. It is also called potential difference. It is measured in volts.
15. What is resistance?
Answer: Resistance is the opposition offered by a material to the flow of current. It depends on material, length, and temperature. It is measured in ohms.
16. What is the unit of current?
Answer: The unit of current is ampere (A). It represents the flow of electric charge per second. It is a basic unit in electrical systems.
17. What is the unit of voltage?
Answer: The unit of voltage is volt (V). It measures the electrical potential difference. It determines how strongly current flows.
18. What is the unit of resistance?
Answer: Resistance is measured in ohms (Ω). It indicates how much a material resists current flow. Higher resistance reduces current.
19. What is power?
Answer: Power is the rate at which electrical energy is used or produced. It is calculated using voltage and current. It is measured in watts.
20. Write the formula for power.
Answer: Power is calculated using the formula P = V × I. Here, V is voltage and I is current. It shows the energy consumption rate.
21. What is a conductor?
Answer: A conductor is a material that allows free flow of electrons. Examples include copper and aluminum. It is used for wiring and electrical connections.
22. What is an insulator?
Answer: An insulator is a material that does not allow electrons to flow easily. Examples include rubber and plastic. It is used for safety in electrical systems.
23. What is a semiconductor?
Answer: A semiconductor has conductivity between conductor and insulator. Its conductivity can be controlled. It is widely used in solar cells and electronics.
24. What is potential difference?
Answer: Potential difference is the difference in voltage between two points. It drives the flow of current in a circuit. It is measured in volts.
25. What is EMF?
Answer: EMF (electromotive force) is the energy supplied per unit charge. It is the source voltage of a system. It helps drive current in a circuit.
26. What does an ammeter measure?
Answer: An ammeter measures electric current in a circuit. It is connected in series. It helps monitor current flow.
27. What does a voltmeter measure?
Answer: A voltmeter measures voltage across two points. It is connected in parallel. It helps measure potential difference.
28. What affects resistance?
Answer: Resistance depends on length, area, material, and temperature. Longer wires have higher resistance. Higher temperature can increase resistance.
29. What is direction of current flow?
Answer: Conventional current flows from higher potential to lower potential. It is opposite to electron flow. This is the standard assumption in circuits.
30. What is electrical power measured in?
Answer: Electrical power is measured in watts (W). It shows the rate of energy consumption. It is important for load calculations.
🔹 Solar Cells (Q31–Q45)
31. What is a solar cell?
Answer: A solar cell is a semiconductor device that converts sunlight into electrical energy. It works on the photovoltaic effect. It produces direct current (DC) electricity.
32. What is photovoltaic effect?
Answer: The photovoltaic effect is the process of converting sunlight into electricity. When light strikes a semiconductor, electrons are energized and flow as current. This is the basic principle of solar cells.
33. What type of current is produced by solar cells?
Answer: Solar cells produce direct current (DC). This current flows in one direction only. It must be converted into AC for most household appliances.
34. What material is used in solar cells?
Answer: Solar cells are mainly made from semiconductor materials such as silicon. These materials have properties suitable for converting light into electricity. Silicon is the most commonly used material.
35. What is the typical voltage of a solar cell?
Answer: A single solar cell produces approximately 0.5 to 0.6 volts. This voltage is too small for practical use. Therefore, multiple cells are connected together.
36. What happens when sunlight falls on a solar cell?
Answer: When sunlight falls on a solar cell, photons transfer energy to electrons. This causes electrons to move and generate electric current. The movement of electrons produces electricity.
37. What are photons?
Answer: Photons are particles of light energy. They carry energy from the sun. When photons strike a solar cell, they excite electrons and generate electricity.
38. What is band gap in a solar cell?
Answer: Band gap is the energy difference between the valence band and conduction band. It determines how efficiently a material converts sunlight into electricity. It is an important property of semiconductors.
39. What are the advantages of solar PV systems?
Answer: Solar PV systems have no moving parts and require low maintenance. They are environmentally friendly and produce clean energy. They can be used in remote locations.
40. What are the limitations of solar PV systems?
Answer: Solar PV systems have relatively low efficiency. They depend on sunlight, so energy generation is intermittent. Initial installation cost can be high.
41. What is diffuse radiation?
Answer: Diffuse radiation is sunlight that is scattered by the atmosphere. It reaches the earth from different directions. Solar panels can still generate power using diffuse light.
42. Why are solar cells considered non-mechanical devices?
Answer: Solar cells do not have any moving parts. They generate electricity directly from sunlight. This reduces wear and tear and increases reliability.
43. Where are solar cells commonly used?
Answer: Solar cells are used in solar panels, calculators, street lights, and satellites. They are also used in remote power systems. They are widely used for renewable energy generation.
44. Why is solar energy intermittent?
Answer: Solar energy depends on sunlight availability. It is not available at night or during cloudy weather. Therefore, its supply is not continuous.
45. What is a solar PV system?
Answer: A solar PV system is a system that converts sunlight into electricity. It includes solar panels, inverter, battery, and other components. It is used for power generation.
🔹 Solar Modules (Q46–Q60)
46. What is a solar module?
Answer: A solar module is an assembly of multiple solar cells connected together. It produces higher voltage and power than a single cell. It is the basic unit of solar panels.
47. Why are solar cells connected together?
Answer: A single solar cell produces very low power. To meet practical energy needs, many cells are connected. This increases voltage and current output.
48. What is a solar panel?
Answer: A solar panel is a collection of solar modules mounted together. It includes a frame and junction box. It is used for installation in the field.
49. What is EVA in solar modules?
Answer: EVA (Ethylene Vinyl Acetate) is a protective material used in solar modules. It encapsulates the cells and protects them from moisture and damage. It also allows light to pass through.
50. What is a backsheet?
Answer: A backsheet is the rear protective layer of a solar module. It protects the module from environmental conditions. It also provides electrical insulation.
51. What is the lifespan of a solar module?
Answer: Solar modules typically last for 20 to 30 years. They are designed for long-term performance. Manufacturers often provide long warranties.
52. What is series connection in solar cells?
Answer: In series connection, the positive terminal of one cell is connected to the negative of another. This increases the total voltage. It is commonly used in modules.
53. What is parallel connection in solar cells?
Answer: In parallel connection, all positive terminals are connected together and all negatives together. This increases current output. It is used when higher current is required.
54. What is a solar array?
Answer: A solar array is a combination of multiple solar panels. It is used for large-scale power generation. It increases total system capacity.
55. What is a junction box in a solar panel?
Answer: A junction box is located at the back of the solar panel. It connects electrical wires and provides output terminals. It also protects connections from environmental damage.
56. What is module efficiency?
Answer: Module efficiency is the ability of a solar panel to convert sunlight into electricity. Higher efficiency means more power output. It depends on material and design.
57. Why is glass used in solar modules?
Answer: Glass is used as the front layer of solar modules. It allows sunlight to pass through while protecting cells. It also provides strength and durability.
58. Are solar modules reliable?
Answer: Yes, solar modules are highly reliable. They have low failure rates and long service life. They require minimal maintenance.
59. What type of power do solar modules produce?
Answer: Solar modules produce direct current (DC) power. This power flows in one direction. It needs to be converted to AC for usage.
60. Where are solar modules installed?
Answer: Solar modules are installed on rooftops or ground-mounted structures. They are placed where maximum sunlight is available. Proper orientation improves efficiency.
🔹 PART 3 (Q61–Q100)
🔹 Charge Controller (Q61–Q70)
61. What is a solar charge controller?
Answer: A solar charge controller is a device that regulates the voltage and current from solar panels to batteries. It ensures safe charging. It prevents damage due to improper charging conditions.
62. Why is a charge controller required?
Answer: A charge controller is required to protect batteries from overcharging and over-discharging. It maintains safe voltage levels. It also improves battery life and system reliability.
63. What does a charge controller regulate?
Answer: It regulates voltage and current coming from solar panels. It ensures batteries receive the correct amount of charge. This prevents damage and improves efficiency.
64. What is overcharging in batteries?
Answer: Overcharging occurs when a battery receives more charge than its capacity. This can cause overheating and damage. It reduces battery life significantly.
65. What is over-discharging?
Answer: Over-discharging happens when a battery is used beyond its safe limit. It can permanently damage the battery. It reduces performance and lifespan.
66. What is reverse current in a solar system?
Answer: Reverse current is the flow of electricity from the battery back to the solar panel. It usually happens at night. A charge controller prevents this loss of energy.
67. How does a charge controller improve efficiency?
Answer: It ensures optimal charging of batteries. It minimizes energy loss and prevents damage. This leads to better utilization of solar energy.
68. What is battery protection?
Answer: Battery protection involves preventing overcharging, over-discharging, and overheating. It ensures safe operation of the battery. It increases battery life.
69. What is temperature compensation?
Answer: Temperature compensation adjusts the charging voltage based on battery temperature. It prevents overheating in hot conditions. It ensures proper charging in cold conditions.
70. Where are charge controllers used?
Answer: Charge controllers are mainly used in off-grid solar systems. They are essential when batteries are present. They ensure safe and efficient system operation.
🔹 Inverter (Q71–Q80)
71. What is an inverter?
Answer: An inverter is a device that converts DC power into AC power. It is used in solar systems. It allows AC appliances to operate.
72. Why is an inverter required in solar systems?
Answer: Solar panels produce DC power, but most appliances use AC power. The inverter converts DC into AC. This makes solar power usable.
73. What is AC power?
Answer: AC (Alternating Current) is a type of current that changes direction periodically. It is used in homes and industries. It is suitable for long-distance transmission.
74. What is DC power?
Answer: DC (Direct Current) flows in one direction only. It is produced by solar panels and batteries. It is used in small electronic devices.
75. What is a rectifier?
Answer: A rectifier is a device that converts AC power into DC power. It is used in electronic devices. It helps supply DC power from AC sources.
76. What is a DC-DC converter?
Answer: A DC-DC converter changes one level of DC voltage to another. It can step up or step down voltage. It is used in solar systems and electronics.
77. What voltage is used in homes in India?
Answer: The standard voltage used in Indian homes is about 230 V AC. It is suitable for household appliances. It is supplied through the grid.
78. Why is DC converted to AC?
Answer: Most household and industrial appliances operate on AC power. Solar systems produce DC power. Therefore, conversion is necessary for usage.
79. Where are inverters used?
Answer: Inverters are used in solar systems, homes, and industries. They help convert DC to AC power. They are essential for solar installations.
80. What is power conversion?
Answer: Power conversion is the process of changing electrical energy from one form to another. It includes AC to DC and DC to AC conversion. It is essential in electrical systems.
🔹 Batteries (Q81–Q90)
81. What is a battery?
Answer: A battery is a device that stores energy in chemical form. It converts this energy into electrical energy when required. It is used for energy storage.
82. What does a battery supply?
Answer: A battery supplies electrical energy to loads. It provides power when solar energy is not available. It ensures continuous power supply.
83. How many terminals does a battery have?
Answer: A battery has two terminals: positive and negative. These terminals allow current flow. They connect the battery to the circuit.
84. What is an anode?
Answer: The anode is the negative terminal of a battery. It releases electrons during discharge. It plays an important role in energy flow.
85. What is a cathode?
Answer: The cathode is the positive terminal of a battery. It receives electrons during discharge. It completes the electrical circuit.
86. What is an electrolyte?
Answer: An electrolyte is a chemical medium that allows ion movement inside the battery. It helps maintain charge balance. It is essential for battery operation.
87. What happens during battery discharge?
Answer: During discharge, stored chemical energy is converted into electrical energy. Electrons flow through the external circuit. This powers connected devices.
88. Why are batteries used in solar systems?
Answer: Batteries store excess energy produced during the day. They supply power at night or during cloudy conditions. This ensures continuous electricity supply.
89. What improves system reliability in solar systems?
Answer: Battery storage improves system reliability. It ensures power availability during interruptions. It stabilizes energy supply.
90. When are batteries most useful?
Answer: Batteries are most useful when sunlight is unavailable. This includes nighttime or cloudy days. They provide backup power.
🔹 Load Calculation & Feasibility (Q91–Q100)
91. What is electrical load?
Answer: Electrical load is any device that consumes electrical energy. Examples include lights, fans, and appliances. It converts electricity into useful forms.
92. What is the formula for energy?
Answer: Energy is calculated using the formula: Energy = Power × Time. It shows how much electricity is consumed. It is measured in kWh.
93. What is 1 kWh?
Answer: 1 kWh is the energy consumed by a 1 kW device in one hour. It is also called one unit of electricity. It is used for billing purposes.
94. Why is load calculation important?
Answer: Load calculation helps determine the size of a solar system. It ensures proper system design. It prevents under-sizing or over-sizing.
95. What is daily energy consumption?
Answer: Daily energy consumption is the total energy used in a day. It is calculated by adding energy used by all devices. It helps in system sizing.
96. What is a feasibility study?
Answer: A feasibility study is an analysis of whether a solar project is viable. It considers technical, financial, and environmental factors. It helps in decision making.
97. What is solar resource assessment?
Answer: Solar resource assessment evaluates sunlight availability at a location. It includes radiation and weather data. It helps estimate energy generation.
98. What is financial analysis in solar projects?
Answer: Financial analysis evaluates the cost and benefits of a solar project. It includes investment, savings, and payback period. It ensures economic viability.
99. What is risk assessment?
Answer: Risk assessment identifies possible risks in a solar project. These may include technical or financial risks. It helps in planning and mitigation.
100. Why is feasibility study important?
Answer: Feasibility study ensures that a solar project is practical and beneficial. It avoids losses and poor planning. It improves project success rate.