Advance Diploma Solar Semester Two Paper 2 Exam Section B

SECTION B – Short Answer Question Bank

50 Questions with Answers (3–4 Lines Each)

(Advanced Diploma Solar Technology – Semester 2 | Paper 2)

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1. What is solar energy?

Answer:
Solar energy is the energy received from the sun in the form of light and heat. It is converted into electricity using solar panels or into heat using solar thermal systems. It is renewable and pollution-free.

2. What is a photovoltaic cell?

Answer:
A photovoltaic (PV) cell is the basic unit of a solar panel. It converts sunlight directly into DC electricity through the photovoltaic effect. Multiple cells are connected to form a module.

3. What is the function of a solar inverter?

Answer:
A solar inverter converts DC power generated by solar panels into AC power. AC power is used by household appliances and can also be supplied to the grid. It also provides protection and monitoring features.

4. What is the purpose of battery storage in solar systems?

Answer:
Battery storage stores excess solar energy generated during daytime. This stored energy can be used at night or during power cuts. It is mainly used in off-grid and hybrid systems.

5. What is net metering?

Answer:
Net metering is a billing system where excess solar electricity is exported to the utility grid. Consumers receive credit for exported units. A bidirectional meter records import and export energy.

6. What is the difference between on-grid and off-grid systems?

Answer:
An on-grid system is connected to the utility grid and usually works without batteries. An off-grid system operates independently and requires batteries for backup. Off-grid systems are useful in remote areas.

7. Why is panel orientation important?

Answer:
Proper orientation ensures maximum sunlight falls on the solar panels. In the Northern Hemisphere, south-facing panels generally give better output. Incorrect orientation reduces generation.

8. What is tilt angle in solar installation?

Answer:
Tilt angle is the angle at which solar panels are installed with respect to the ground. Correct tilt improves sunlight capture and energy output. It depends on location and latitude.

9. What is shading analysis?

Answer:
Shading analysis identifies shadows from trees, buildings, or nearby objects falling on panels. Even partial shading can reduce output significantly. It is an important step before installation.

10. What is a mounting structure?

Answer:
A mounting structure supports solar panels mechanically. It keeps modules fixed safely on rooftops or ground. It is generally made of GI, aluminium, or steel.

11. What is the function of a combiner box?

Answer:
A combiner box combines outputs of multiple solar strings into one output line. It contains fuses, SPD, and disconnect switches. It improves safety and simplifies wiring.

12. What is the use of earthing in solar plants?

Answer:
Earthing provides a safe path for leakage current and fault current. It protects people and equipment from shock and damage. Proper earthing is essential in every PV system.

13. What is a fuse and why is it used?

Answer:
A fuse is a protection device that melts when current exceeds safe limits. It protects cables and equipment from overcurrent damage. It is commonly used in DC and AC circuits.

14. What is an SPD?

Answer:
SPD stands for Surge Protection Device. It protects solar equipment from voltage surges caused by lightning or switching. It increases system reliability.

15. What is the purpose of PPE during installation?

Answer:
PPE means Personal Protective Equipment such as helmets, gloves, shoes, and harnesses. It protects workers from injuries during installation. PPE is mandatory for site safety.

16. Why is roof load capacity checked?

Answer:
Roof load capacity is checked to ensure the roof can safely bear panel and structure weight. Weak roofs may crack or fail. It is important for rooftop systems.

17. What is soil investigation in ground-mounted plants?

Answer:
Soil investigation studies soil strength and condition before foundation work. It helps decide pile depth and structure design. It is essential for large ground-mounted plants.

18. What is commissioning of a solar plant?

Answer:
Commissioning is the final process before plant operation starts. It includes testing, inspection, and performance checks. After successful commissioning, the plant is energized.

19. What is preventive maintenance?

Answer:
Preventive maintenance means regular inspection and servicing before faults occur. It includes cleaning panels, checking wiring, and tightening connections. It increases plant life.

20. Why is regular cleaning of modules necessary?

Answer:
Dust, bird droppings, and dirt block sunlight reaching the cells. This reduces generation efficiency. Regular cleaning helps maintain maximum output.

21. What is thermal imaging in solar plants?

Answer:
Thermal imaging uses infrared cameras to detect hot spots and abnormal heating. It helps identify faulty modules or loose connections. It is useful in maintenance.

22. What is performance ratio?

Answer:
Performance ratio compares actual plant generation with expected generation. It indicates overall system efficiency. Higher PR means better plant performance.

23. What is a Gantt chart?

Answer:
A Gantt chart is a project planning tool showing activities against time. It helps track progress and deadlines. It is widely used in solar project execution.

24. What is BOM in solar projects?

Answer:
BOM means Bill of Materials. It lists all components, quantities, and specifications required for the project. It helps procurement and cost planning.

25. What is procurement?

Answer:
Procurement is the process of purchasing project materials and equipment. It includes vendor selection, ordering, and delivery. Good procurement ensures timely completion.

26. Why are DC polarity checks important?

Answer:
DC polarity checks confirm correct positive and negative cable connections. Wrong polarity may damage inverters and equipment. Therefore it is done before energization.

27. What is a string inverter?

Answer:
A string inverter converts DC from a group of solar modules connected in series. It is commonly used in residential and commercial systems. It is economical and efficient.

28. What is a microinverter?

Answer:
A microinverter is installed on each solar panel individually. It converts DC to AC at module level. It performs better under partial shading conditions.

29. What is the role of data logger?

Answer:
A data logger records voltage, current, power, and energy generation data. It helps monitor system performance. It is useful for remote diagnostics.

30. What is load profile study?

Answer:
Load profile study analyzes electricity consumption over time. It helps determine peak demand and system sizing. It is important before designing solar plants.

31. Why is cable sizing important?

Answer:
Correct cable sizing avoids overheating and voltage drop. Undersized cables waste energy and create hazards. Proper cable selection improves efficiency.

32. What is voltage drop?

Answer:
Voltage drop is the reduction in voltage while electricity flows through cables. Long or undersized cables cause higher voltage drop. It should be minimized.

33. What is a hybrid solar system?

Answer:
A hybrid system combines solar panels, batteries, and grid supply. It provides backup during outages and allows energy savings. It is flexible and reliable.

34. What is anti-islanding protection?

Answer:
Anti-islanding protection disconnects the inverter when grid power fails. It prevents power feeding into dead lines. This protects utility workers and equipment.

35. Why is monitoring important in solar plants?

Answer:
Monitoring tracks generation, faults, and equipment status. It helps quick troubleshooting and better maintenance. Continuous monitoring improves plant uptime.

36. What are bifacial solar panels?

Answer:
Bifacial panels generate power from both front and rear sides. Rear side uses reflected sunlight. They can increase total energy output.

37. What is ROI in solar projects?

Answer:
ROI means Return on Investment. It measures financial return from solar installation over time. It helps assess project profitability.

38. Why is solar energy environmentally beneficial?

Answer:
Solar energy reduces dependence on fossil fuels. It lowers greenhouse gas emissions and air pollution. It is clean and sustainable.

39. What is ACDB?

Answer:
ACDB stands for AC Distribution Board. It receives inverter AC output and provides protection/distribution to loads or grid. It contains breakers and safety devices.

40. What is DCCB?

Answer:
DCCB stands for DC Combiner/Distribution Box. It combines PV strings and provides DC side protection. It improves safe system operation.

41. Why are labels and signs used in plants?

Answer:
Labels identify circuits, danger zones, and equipment ratings. They improve safety and simplify maintenance. Clear signage is important in industrial plants.

42. What is a critical path in project management?

Answer:
Critical path is the sequence of tasks affecting total project completion time. Delay in critical activities delays the whole project. It is used for schedule control.

43. Why is site security important?

Answer:
Site security prevents theft, vandalism, and unauthorized access. It protects costly solar equipment and workers. It is important during construction and operation.

44. What is module degradation?

Answer:
Module degradation is the gradual reduction in panel output over years. It happens naturally due to aging and weather exposure. Typical reduction is small annually.

45. What is the use of harness in rooftop work?

Answer:
A safety harness protects workers from falling from roofs. It is attached to anchor points during installation. It is essential for height safety.

46. What is energy yield analysis?

Answer:
Energy yield analysis estimates expected annual electricity generation. It considers sunlight, shading, temperature, and system losses. It supports project feasibility.

47. What is the advantage of remote monitoring?

Answer:
Remote monitoring allows plant data to be checked from any location. Faults can be detected quickly. It saves inspection time and cost.

48. What is the use of lightning arrestor?

Answer:
A lightning arrestor protects structures and equipment from lightning strikes. It safely diverts surge current to ground. It is important in open sites.

49. What is the benefit of proper installation?

Answer:
Proper installation ensures safety, maximum output, and long equipment life. It reduces faults and maintenance costs. Quality installation improves ROI.

50. Why is solar power considered future energy?

Answer:
Solar power is abundant, renewable, and clean. Technology costs are reducing every year. It supports sustainable development and energy independence.