Q.1 What is the main function of a solar panel?
To generate mechanical energy
To convert sunlight into electrical energy
To store electricity
To regulate temperature
Explanation - Solar panels, also called photovoltaic (PV) modules, use the photovoltaic effect to convert photons from sunlight directly into electricity.
Correct answer is: To convert sunlight into electrical energy
Q.2 Which part of a solar panel receives the most sunlight?
The rear side
The glass cover
The front surface
The metal frame
Explanation - The front surface of the panel is exposed to sunlight and contains the semiconductor cells that generate electricity.
Correct answer is: The front surface
Q.3 What does the acronym PV stand for?
Power Vector
Photovoltaic
Pulse Voltage
Phase Voltage
Explanation - PV is short for Photovoltaic, which refers to the technology that converts light into electricity.
Correct answer is: Photovoltaic
Q.4 Which gas is primarily responsible for the greenhouse effect?
Oxygen
Methane
Carbon Dioxide
Nitrogen
Explanation - Carbon dioxide (CO₂) traps heat in the atmosphere, contributing significantly to global warming.
Correct answer is: Carbon Dioxide
Q.5 Which of these is NOT a type of renewable energy?
Solar
Wind
Natural Gas
Hydropower
Explanation - Natural gas is a fossil fuel, whereas solar, wind, and hydropower are renewable sources of energy.
Correct answer is: Natural Gas
Q.6 What is the main purpose of an inverter in a solar power system?
To store energy
To convert DC to AC
To regulate voltage
To cool the panels
Explanation - Solar panels produce direct current (DC). An inverter transforms this DC into alternating current (AC) used in homes.
Correct answer is: To convert DC to AC
Q.7 Which material is commonly used in silicon solar cells?
Copper
Gallium
Silicon
Aluminum
Explanation - Silicon, especially high‑purity silicon, is the primary semiconductor material in most commercial PV cells.
Correct answer is: Silicon
Q.8 What does the efficiency of a solar panel refer to?
Its size in square meters
The percentage of sunlight it can absorb
The ratio of electricity produced to sunlight received
Its weight
Explanation - Efficiency measures how well a panel converts incident solar irradiance into usable electrical power.
Correct answer is: The ratio of electricity produced to sunlight received
Q.9 Which of the following is a disadvantage of rooftop solar installations?
High initial cost
Low maintenance
Unlimited lifespan
Low power output during cloudy days
Explanation - Cloud cover reduces solar irradiance, leading to lower output; other options are not true disadvantages.
Correct answer is: Low power output during cloudy days
Q.10 Which country currently leads in global solar PV capacity?
United States
China
Germany
India
Explanation - China has the largest installed solar photovoltaic capacity, followed by the US and India.
Correct answer is: China
Q.11 What is a common way to track the sun for maximum energy capture?
Fixed tilt
Single-axis tracking
Manual adjustment daily
Dual-axis tracking only
Explanation - Single‑axis tracking follows the sun east‑to‑west, improving energy capture over fixed panels.
Correct answer is: Single-axis tracking
Q.12 The term ‘solar irradiance’ refers to:
Solar panel efficiency
Solar radiation per unit area
Sunlight reflected by the earth
Temperature of the sun
Explanation - Irradiance is the power received per unit area from the sun, measured in watts per square meter.
Correct answer is: Solar radiation per unit area
Q.13 Which semiconductor material is used in thin‑film solar cells?
Silicon
Cadmium Telluride
Gallium Nitride
Graphene
Explanation - Cadmium telluride (CdTe) is a common material for thin‑film PV due to its high absorption coefficient.
Correct answer is: Cadmium Telluride
Q.14 What does the term ‘module’ refer to in a PV system?
An entire solar power plant
A single solar cell
A connected array of solar cells
The inverter unit
Explanation - A module is a group of cells wired together; multiple modules form a solar array.
Correct answer is: A connected array of solar cells
Q.15 Which parameter is NOT directly affected by the temperature of a PV module?
Open‑circuit voltage
Short‑circuit current
Maximum power point
Fill factor
Explanation - Short‑circuit current is relatively stable with temperature, whereas voltage, power point, and fill factor decrease.
Correct answer is: Short‑circuit current
Q.16 The maximum power point (MPP) of a PV module is the point where:
Voltage is zero
Current is maximum
Power output is maximum
Resistance is minimal
Explanation - MPP is where the product of voltage and current (power) reaches its peak for a given irradiance.
Correct answer is: Power output is maximum
Q.17 Which of the following best describes a ‘grid‑connected’ PV system?
It stores all energy on-site
It is directly linked to the electrical grid
It uses battery storage only
It operates independently of the grid
Explanation - Grid‑connected systems feed excess power to the utility network and can draw power when panels are idle.
Correct answer is: It is directly linked to the electrical grid
Q.18 What is a ‘net‑metering’ scheme?
A method for measuring panel output
A policy that credits solar producers for net power fed into the grid
A meter that only measures consumption
A device that measures solar irradiance
Explanation - Net metering allows users to offset their consumption by feeding surplus solar electricity back to the grid, receiving credit.
Correct answer is: A policy that credits solar producers for net power fed into the grid
Q.19 Which of the following is a major challenge for solar farms in arid regions?
High humidity
Dust accumulation on panels
Frequent cloud cover
Lack of sunlight
Explanation - Dust and sand can significantly reduce panel efficiency in dry, dusty climates, requiring regular cleaning.
Correct answer is: Dust accumulation on panels
Q.20 The ‘fill factor’ of a PV cell is calculated as:
Vmp / Voc
Imp / Isc
Pmp / (Voc × Isc)
Pmp / (Vmp × Imp)
Explanation - Fill factor = (Vmp × Imp) ÷ (Voc × Isc), representing the squareness of the IV curve.
Correct answer is: Pmp / (Voc × Isc)
Q.21 Which of the following is NOT a factor affecting the design of a rooftop PV installation?
Roof orientation
Local weather patterns
Availability of battery storage
The color of the roof shingles
Explanation - Roof color has negligible impact on solar panel performance compared to orientation, shading, and temperature.
Correct answer is: The color of the roof shingles
Q.22 Which certification indicates that a solar module meets specific quality and performance standards?
ISO 9001
UL 1703
IEEE 1547
IEC 61850
Explanation - UL 1703 is the standard for PV modules, ensuring safety and performance compliance.
Correct answer is: UL 1703
Q.23 What is the primary purpose of a ‘maximum power point tracker’ (MPPT)?
To regulate panel temperature
To adjust the DC voltage to the optimum point for maximum power
To store excess energy
To monitor electricity consumption
Explanation - MPPT optimizes the power output of the PV system by continuously tracking the maximum power point of the panel array.
Correct answer is: To adjust the DC voltage to the optimum point for maximum power
Q.24 Which type of solar cell is considered a 'monocrystalline' cell?
Single‑crystal silicon
Polycrystalline silicon
Amorphous silicon
Thin‑film silicon
Explanation - Monocrystalline cells are made from a single silicon crystal, offering higher efficiency.
Correct answer is: Single‑crystal silicon
Q.25 What is the function of a ‘charge controller’ in a solar battery system?
To convert AC to DC
To regulate the voltage and current entering the battery
To increase battery capacity
To disconnect the battery during a fault
Explanation - The charge controller protects batteries from overcharging by regulating input voltage and current.
Correct answer is: To regulate the voltage and current entering the battery
Q.26 Which parameter is most critical for determining the size of a battery storage system?
Peak sun hours per day
Panel efficiency
Battery depth of discharge
Inverter type
Explanation - Peak sun hours indicate the effective sunlight available for charging, directly impacting battery sizing.
Correct answer is: Peak sun hours per day
Q.27 Which of these is NOT a type of solar thermal energy system?
Flat‑plate collectors
Evacuated tube collectors
Concentrated Solar Power (CSP)
Photovoltaic panels
Explanation - PV panels produce electricity, while the other three are used to capture and transfer solar heat.
Correct answer is: Photovoltaic panels
Q.28 What is the main advantage of bifacial solar panels?
Lower cost
Higher temperature tolerance
They can harvest light from both sides
Smaller footprint
Explanation - Bifacial panels absorb light on the front and back surfaces, improving energy yield, especially on reflective surfaces.
Correct answer is: They can harvest light from both sides
Q.29 Which policy instrument provides financial incentives for renewable energy deployment?
Tariff rates
Renewable Portfolio Standards (RPS)
Carbon pricing
All of the above
Explanation - Tariffs, RPS, and carbon pricing all influence renewable energy uptake by affecting costs and market dynamics.
Correct answer is: All of the above
Q.30 The term ‘levelized cost of energy (LCOE)’ refers to:
The total cost of a system over its lifetime divided by total energy produced
The price of electricity in the market
The cost of building a solar panel
The energy output per panel
Explanation - LCOE represents the average cost per unit of energy generated, enabling cost comparisons.
Correct answer is: The total cost of a system over its lifetime divided by total energy produced
Q.31 Which of the following is a key benefit of using solar power for water pumping in rural areas?
Reduced water quality
Lower operating costs
Higher pumping speed
Decreased sunlight availability
Explanation - Solar pumps eliminate fuel expenses and require minimal maintenance, lowering long‑term operating costs.
Correct answer is: Lower operating costs
Q.32 What is the typical lifespan of a modern commercial solar PV module?
5-10 years
10-15 years
25-30 years
50-60 years
Explanation - Manufacturers often guarantee performance for 25+ years, with modules often lasting longer.
Correct answer is: 25-30 years
Q.33 Which of these is a characteristic of a ‘smart inverters’?
Fixed output voltage
Communication with the grid for demand response
No monitoring capability
Only DC output
Explanation - Smart inverters can interact with grid management systems to provide services such as voltage regulation.
Correct answer is: Communication with the grid for demand response
Q.34 Solar panels are rated at a particular temperature coefficient. What does a negative coefficient mean?
Efficiency increases with temperature
Efficiency decreases with temperature
Efficiency stays the same
Panel temperature is regulated
Explanation - A negative temperature coefficient indicates that panel output falls as the temperature rises.
Correct answer is: Efficiency decreases with temperature
Q.35 Which type of mounting system is most common for residential rooftop PV?
Ballasted mounting
Fixed‑tilt mounting
Tracking mounting
Pole mounting
Explanation - Fixed‑tilt systems are simple, low‑cost, and widely used for residential installations.
Correct answer is: Fixed‑tilt mounting
Q.36 What is the purpose of a ‘solar fuse’?
To protect the inverter from voltage spikes
To limit current flow and protect wiring from overcurrent
To increase panel efficiency
To cool the PV array
Explanation - Solar fuses safeguard the system by breaking the circuit if current exceeds safe limits.
Correct answer is: To limit current flow and protect wiring from overcurrent
Q.37 Which factor is primarily responsible for the 'diurnal' variation in solar power generation?
Panel orientation
Atmospheric absorption
Time of day affecting irradiance
Battery storage
Explanation - Solar irradiance peaks around noon; panels produce less power before sunrise and after sunset.
Correct answer is: Time of day affecting irradiance
Q.38 A ‘grid‑parity’ point occurs when:
Solar energy equals fossil fuel energy
Solar electricity cost equals grid electricity cost
Panel efficiency reaches 100%
Inverter efficiency is 100%
Explanation - Grid‑parity means the cost of solar‑generated electricity is equal to the price from the grid.
Correct answer is: Solar electricity cost equals grid electricity cost
Q.39 Which of the following is a typical application of solar power in agriculture?
Solar‑powered irrigation pumps
Solar heating of soil
Solar lighting for night work
All of the above
Explanation - Solar energy can support irrigation, heating, and lighting to improve agricultural productivity.
Correct answer is: All of the above
Q.40 What is the most common way to mitigate panel degradation over time?
Regular cleaning
Increasing temperature
Reducing panel angle
Adding a second layer of panels
Explanation - Cleaning removes dust and debris that can cause performance losses.
Correct answer is: Regular cleaning
Q.41 Which component of a PV system can be used to monitor performance in real time?
Inverter
Mounting rack
Solar panel
Battery
Explanation - Many modern inverters provide telemetry for voltage, current, and power output monitoring.
Correct answer is: Inverter
Q.42 In the context of solar energy, what does the acronym 'MPPT' stand for?
Maximum Power Point Tracking
Multi‑Phase Power Transmission
Minimum Power Performance Test
Modular Power Process Technology
Explanation - MPPT refers to the electronic technique that maximizes power extraction from PV panels.
Correct answer is: Maximum Power Point Tracking
Q.43 Which of these is an example of a ‘passive’ solar design strategy for buildings?
Solar panels
Solar hot water system
South‑facing windows
Solar‑powered street lights
Explanation - South‑facing windows capture natural daylight and heat, a passive approach, whereas panels are active.
Correct answer is: South‑facing windows
Q.44 Which material is used in organic photovoltaic (OPV) cells?
Silicon
Perovskite
Polymer-based blends
Graphite
Explanation - OPV cells use organic polymers or small molecules as light‑absorbing semiconductors.
Correct answer is: Polymer-based blends
Q.45 A solar farm in a region with a high albedo surface typically experiences:
Lower efficiency due to heat
Higher efficiency due to reflected light
No change in efficiency
More shading
Explanation - High albedo surfaces reflect more sunlight back onto panels, boosting their output.
Correct answer is: Higher efficiency due to reflected light
Q.46 The 'BEP' of a solar power plant refers to:
Break‑Even Point
Best‑Effort Performance
Battery Energy Production
Base‑Electricity Price
Explanation - BEP is the point at which total revenues equal total costs, indicating profitability.
Correct answer is: Break‑Even Point
Q.47 Which of the following is a major advantage of thin‑film solar cells over crystalline silicon?
Higher efficiency
Lower cost of materials
Greater durability in heat
Higher power density
Explanation - Thin‑film cells require less silicon, making them cheaper to produce, albeit with lower efficiency.
Correct answer is: Lower cost of materials
Q.48 What is the primary purpose of a 'battery management system (BMS)'?
To increase battery capacity
To monitor and protect the battery from overcharge or over‑discharge
To convert AC to DC
To connect batteries to the grid
Explanation - A BMS safeguards battery health by controlling charge/discharge cycles and ensuring safety.
Correct answer is: To monitor and protect the battery from overcharge or over‑discharge
Q.49 In solar photovoltaic terminology, what does 'string' refer to?
Series connection of cells
Series connection of modules
Parallel connection of modules
Group of inverters
Explanation - A string is a series of PV modules wired together to provide the desired voltage to an inverter.
Correct answer is: Series connection of modules
Q.50 Which of the following is a major environmental benefit of solar power?
Increased air pollution
Reduced greenhouse gas emissions
Higher water consumption
Higher noise pollution
Explanation - Solar power generates electricity with minimal CO₂ emissions compared to fossil fuels.
Correct answer is: Reduced greenhouse gas emissions
Q.51 Which of the following is an example of a 'hybrid' PV system?
PV + Wind
PV + Battery
PV + Diesel generator
All of the above
Explanation - Hybrid systems combine PV with other power sources or storage for improved reliability.
Correct answer is: All of the above
Q.52 The 'silicon wafer' in a solar cell is typically:
Thin and flexible
Doped with impurities
Transparent
Metallic
Explanation - Silicon wafers are doped to create p‑type and n‑type layers essential for charge separation.
Correct answer is: Doped with impurities
Q.53 Which of the following is a key disadvantage of solar energy?
High initial capital cost
Low maintenance
High reliability
Unlimited resource
Explanation - The upfront cost of PV equipment and installation is often higher than conventional energy sources.
Correct answer is: High initial capital cost
Q.54 What does the acronym 'PV' stand for in the context of solar energy?
Power Voltage
Photovoltaic
Panel Voltage
Photonic Vision
Explanation - PV refers to the technology that converts light (photons) into electricity using semiconductors.
Correct answer is: Photovoltaic
Q.55 Which component in a PV system is responsible for converting DC to AC?
Battery
Inverter
Solar panel
Charge controller
Explanation - An inverter transforms direct current from the panels into alternating current compatible with the grid.
Correct answer is: Inverter
Q.56 The color of a solar panel is usually:
Yellow
Red
Blue
Black
Explanation - The black surface of panels absorbs more light, improving efficiency.
Correct answer is: Black
Q.57 A sunny day can produce more electricity than a cloudy day because:
Solar panels are heavier on sunny days
Sunlight intensity is higher
Panels are cooler
Clouds generate electricity
Explanation - Higher irradiance on sunny days increases the electrical output of PV panels.
Correct answer is: Sunlight intensity is higher
Q.58 Which of the following is a typical benefit of solar panels for households?
Lower utility bills
Higher electricity bills
More dependence on the grid
Increased fuel costs
Explanation - Solar panels provide free electricity, reducing reliance on the utility and lowering bills.
Correct answer is: Lower utility bills
Q.59 What happens to a solar panel's output as its temperature increases?
Output increases
Output decreases
Output stays the same
Output fluctuates randomly
Explanation - Higher temperatures reduce the voltage of PV cells, lowering overall power output.
Correct answer is: Output decreases
Q.60 Which device is used to check how much power a solar panel is producing?
Meter
Thermometer
Barometer
Altimeter
Explanation - A solar meter or multimeter measures the electrical output of the panels.
Correct answer is: Meter
Q.61 The shape of the curve that shows a solar panel's voltage vs. current is called the:
Sine curve
Square wave
IV curve
Clockwise loop
Explanation - An IV curve plots voltage against current to analyze a PV cell's performance.
Correct answer is: IV curve
Q.62 In a solar array, the 'maximum power point' is the point where:
Voltage is zero
Current is maximum
Power output is maximum
Temperature is lowest
Explanation - The MPP is the operating point that delivers the most power under given conditions.
Correct answer is: Power output is maximum
Q.63 Which factor does NOT affect the efficiency of a solar panel?
Panel age
Ambient temperature
Angle of incidence
Panel color
Explanation - Color has negligible influence on efficiency; angle, temperature, and aging do.
Correct answer is: Panel color
Q.64 What is the purpose of a 'shading analysis' for a solar project?
To check aesthetic design
To identify potential shading losses
To calculate panel color
To measure wind speed
Explanation - Shading analysis evaluates how nearby objects might reduce panel performance.
Correct answer is: To identify potential shading losses
Q.65 Which of the following is a primary consideration for placing a solar farm in a desert region?
High humidity
High dust accumulation
Low sun angle
Abundant shade
Explanation - Deserts have high dust, which can reduce panel efficiency if not cleaned regularly.
Correct answer is: High dust accumulation
Q.66 Which type of solar system can provide power during grid outages?
Grid‑connected only
Off‑grid with battery backup
Solar‑only with no inverter
Inverter‑only
Explanation - Off‑grid systems store energy in batteries, allowing power supply during outages.
Correct answer is: Off‑grid with battery backup
Q.67 The term 'perovskite' is associated with:
A type of solar panel mounting
A type of solar cell material
A software used for modeling
A brand of inverters
Explanation - Perovskite refers to a crystal structure used in emerging high‑efficiency solar cells.
Correct answer is: A type of solar cell material
Q.68 What is the main reason for using a 'string breaker' in a PV system?
To increase panel temperature
To disconnect a string safely during faults
To boost voltage
To reduce shading
Explanation - String breakers isolate faulty strings to protect the rest of the array and allow maintenance.
Correct answer is: To disconnect a string safely during faults
Q.69 Which of the following best describes a 'fixed‑tilt' solar array?
Tracks the sun continuously
Has a constant angle relative to the ground
Tilts daily by manual effort
Tilts at night
Explanation - Fixed‑tilt arrays maintain a single orientation; they do not follow the sun's movement.
Correct answer is: Has a constant angle relative to the ground
Q.70 The 'output voltage' of a typical residential solar panel is usually:
50–60 V
100–120 V
200–240 V
400–500 V
Explanation - Residential panels produce around 100–120 V DC, suitable for inverter conversion.
Correct answer is: 100–120 V
Q.71 In solar thermal applications, what is the purpose of a 'heat‑pipe'?
To transfer heat from the absorber to the storage fluid
To store solar panels
To cool the panels
To reflect sunlight
Explanation - Heat‑pipes efficiently move thermal energy from the collector to the storage medium.
Correct answer is: To transfer heat from the absorber to the storage fluid
Q.72 Which of these is a typical method to improve the performance of solar panels in high‑temperature environments?
Use a larger panel area
Install cooling fans or heat sinks
Use thicker glass
Reduce panel angle
Explanation - Active or passive cooling reduces panel temperature, boosting efficiency.
Correct answer is: Install cooling fans or heat sinks
Q.73 Which of the following is a key benefit of using solar energy in remote villages?
Increased air pollution
Reliable electricity access
Dependence on the national grid
Higher fuel consumption
Explanation - Solar power can provide off‑grid electricity to remote areas, improving quality of life.
Correct answer is: Reliable electricity access
Q.74 Which component is NOT part of a typical grid‑connected solar system?
Solar panels
Inverter
Battery bank
Meter
Explanation - Grid‑connected systems usually do not store energy, although optional batteries can be added.
Correct answer is: Battery bank
Q.75 Which of the following represents a primary advantage of solar photovoltaic over solar thermal?
Higher efficiency at low light
Lower cost
No moving parts
Higher heat generation
Explanation - PV systems have no mechanical components, reducing maintenance compared to thermal systems.
Correct answer is: No moving parts
Q.76 What is the typical lifespan of an inverters in a solar PV system?
5 years
10 years
15–20 years
30 years
Explanation - Inverters are usually rated for 15–20 years, often longer with proper maintenance.
Correct answer is: 15–20 years
Q.77 Which of these factors most directly influences the amount of sunlight a solar panel receives?
Wind speed
Latitude
Panel color
Battery capacity
Explanation - Latitude determines the sun's angle, affecting irradiance and panel output.
Correct answer is: Latitude
Q.78 The term 'grid parity' refers to:
When solar power equals fossil fuel power in cost
When the grid can handle all solar production
When panels produce the same power as the grid
When solar panels match grid voltage
Explanation - Grid parity is reached when solar-generated electricity costs the same as conventional grid electricity.
Correct answer is: When solar power equals fossil fuel power in cost
Q.79 Which type of solar panel is known for high efficiency but also higher cost?
Thin‑film
Monocrystalline
Polycrystalline
Amorphous
Explanation - Monocrystalline panels offer the best performance at a premium price.
Correct answer is: Monocrystalline
Q.80 What is the purpose of 'anti‑reflection coatings' on PV cells?
To increase panel temperature
To reduce light reflection and increase absorption
To protect against dust
To enhance panel flexibility
Explanation - Anti‑reflection layers improve light absorption, boosting cell efficiency.
Correct answer is: To reduce light reflection and increase absorption
Q.81 The 'maximum power point tracking' (MPPT) algorithm helps a solar inverter:
Increase the panel temperature
Select the optimal voltage for maximum power output
Reduce the panel's physical size
Store excess energy
Explanation - MPPT continuously adjusts the inverter load to operate the PV array at its maximum power point.
Correct answer is: Select the optimal voltage for maximum power output
Q.82 Which of the following is a common method to mitigate dust buildup on rooftop panels?
Use a dust‑free roof
Install a water‑based cleaning system
Paint panels black
Install a shading screen
Explanation - Automated cleaning systems can maintain panel performance by removing dust and debris.
Correct answer is: Install a water‑based cleaning system
Q.83 Which of the following is a key parameter in calculating a PV system’s design?
Panel color
System voltage
Panel shape
Panel thickness
Explanation - System voltage determines string configuration and inverter compatibility.
Correct answer is: System voltage
Q.84 A 'single‑axis' solar tracker follows the sun in which direction?
North‑South
East‑West
Vertical
Horizontal
Explanation - Single‑axis trackers rotate on an axis perpendicular to the east–west line.
Correct answer is: East‑West
Q.85 Which of these is a major benefit of using bifacial solar panels?
Higher manufacturing cost
Increased maintenance
Higher energy yield
Reduced power output
Explanation - Bifacial panels capture light from both sides, leading to higher overall energy production.
Correct answer is: Higher energy yield
Q.86 What does 'LCOE' stand for in solar economics?
Levelized Cost of Energy
Loss of Conversion Energy
Light Capacity Output Energy
Load Control Output Energy
Explanation - LCOE is a metric that calculates the average cost per unit of energy produced over a system’s life.
Correct answer is: Levelized Cost of Energy
Q.87 Which of the following is a typical application of solar-powered street lights?
Providing lighting in remote areas
Powering high‑speed trains
Heating industrial furnaces
Generating electricity for large cities only
Explanation - Solar street lights are used in remote or off‑grid areas where grid access is limited.
Correct answer is: Providing lighting in remote areas
Q.88 Which type of solar energy technology directly converts light into heat for heating?
Photovoltaic
Photothermoelectric
Solar thermal
Solar wind
Explanation - Solar thermal systems capture sunlight’s heat for water or air heating.
Correct answer is: Solar thermal
Q.89 The 'temperature coefficient' of a solar panel is expressed as:
Percentage decrease in power per degree Celsius rise
Power per watt of solar irradiance
Voltage at open‑circuit
Current at short‑circuit
Explanation - Temperature coefficient indicates how much the panel’s output degrades per °C increase.
Correct answer is: Percentage decrease in power per degree Celsius rise
Q.90 What is the function of a 'string breaker' in a PV system?
Increase voltage
Isolate faulty string
Boost current
Reduce temperature
Explanation - String breakers disconnect a defective string, protecting the rest of the array.
Correct answer is: Isolate faulty string
Q.91 Which of the following is a potential challenge when deploying solar farms in arid regions?
Low sunlight intensity
High humidity
Dust accumulation
Frequent snow
Explanation - Dust can accumulate on panels, reducing efficiency if not cleaned.
Correct answer is: Dust accumulation
Q.92 In a solar power system, what does a 'charge controller' primarily do?
Convert DC to AC
Prevent battery overcharge
Store solar energy
Increase panel temperature
Explanation - Charge controllers regulate current to protect batteries from overcharging.
Correct answer is: Prevent battery overcharge
Q.93 Which of these is NOT an advantage of solar power?
Low operating costs
No fuel consumption
High environmental impact
Renewable resource
Explanation - Solar power has minimal environmental impact compared to fossil fuels.
Correct answer is: High environmental impact
Q.94 Solar panels are typically mounted on:
Water
Wood
Steel or aluminum frames
Concrete
Explanation - Frames provide structural support and secure the panels against wind and load.
Correct answer is: Steel or aluminum frames
Q.95 Which type of solar cell has the highest commercial efficiency as of 2025?
Monocrystalline silicon
Polycrystalline silicon
Amorphous silicon
Perovskite
Explanation - Perovskite cells have achieved commercial efficiencies above 22% with promising cost curves.
Correct answer is: Perovskite
Q.96 Which of the following is an example of a 'utility‑scale' solar installation?
A rooftop system for a single home
An industrial solar array covering several acres
A small garden solar lamp
A portable solar charger
Explanation - Utility‑scale refers to large installations that supply power to the grid.
Correct answer is: An industrial solar array covering several acres
Q.97 The 'inverter's duty cycle' refers to:
The frequency of power conversion
The portion of time it actively converts DC to AC
The battery charging rate
The panel temperature rise
Explanation - Inverter duty cycle indicates how often it is operating relative to total time.
Correct answer is: The portion of time it actively converts DC to AC
Q.98 Which component is critical for converting DC power from solar panels into AC power usable by household appliances?
Solar panel
Battery
Inverter
Charge controller
Explanation - The inverter is the device that performs DC to AC conversion.
Correct answer is: Inverter
Q.99 Which of the following is a common benefit of using solar PV in developing countries?
Increased dependence on diesel generators
Lower electricity costs
Higher greenhouse gas emissions
More fuel consumption
Explanation - Solar PV can reduce energy costs and improve access to reliable electricity.
Correct answer is: Lower electricity costs
Q.100 Solar panels produce electricity through the:
Electromagnetic induction
Photovoltaic effect
Thermal conduction
Chemical reaction
Explanation - Photovoltaic effect is the conversion of light photons into electric current in a semiconductor.
Correct answer is: Photovoltaic effect
Q.101 What is the main advantage of solar panels over wind turbines for urban residential use?
They require a large footprint
They produce noise
They are quiet and compact
They need frequent maintenance
Explanation - Solar panels are silent and can be installed on roofs, making them suitable for residential settings.
Correct answer is: They are quiet and compact
Q.102 Which of the following best describes a 'grid‑connected' solar system?
It operates only at night
It is isolated from the national grid
It feeds power to the grid and can draw from it
It uses batteries only
Explanation - Grid‑connected systems integrate with the utility, allowing export and import of electricity.
Correct answer is: It feeds power to the grid and can draw from it
Q.103 In a photovoltaic system, the 'open‑circuit voltage (Voc)' is:
The voltage when the panel is shorted
The maximum voltage when no load is connected
The voltage when the panel is fully loaded
The voltage at maximum power point
Explanation - Voc is the highest voltage produced when the panel's output terminals are open.
Correct answer is: The maximum voltage when no load is connected
Q.104 Which of the following is NOT typically considered when sizing a PV system?
Daily energy consumption
Panel efficiency
Local wind speed
Battery depth of discharge
Explanation - Wind speed influences wind energy, not photovoltaic system design.
Correct answer is: Local wind speed
Q.105 Which of the following best explains 'stochastic weather variations' in solar forecasting?
Predictable patterns of sunlight
Random fluctuations in sunlight and cloud cover
Seasonal temperature changes
Annual wind speed variations
Explanation - Stochastic weather variations refer to the unpredictable changes in sunlight due to weather.
Correct answer is: Random fluctuations in sunlight and cloud cover
Q.106 In the context of solar energy, what is the 'power output' of a panel measured in?
Watts
Volts
Amperes
Hertz
Explanation - Power is the rate at which energy is produced, measured in watts.
Correct answer is: Watts
Q.107 Which of the following is a benefit of using a 'smart inverter'?
Increased shading
Real‑time monitoring and grid support
Higher cost
No communication capability
Explanation - Smart inverters can communicate with the grid to provide services like voltage regulation.
Correct answer is: Real‑time monitoring and grid support
Q.108 The term 'diel cycle' in solar energy refers to:
The day–night cycle affecting irradiance
The weekly maintenance schedule
The annual temperature range
The seasonal shift in panel orientation
Explanation - 'Diel cycle' describes the daily pattern of solar irradiance due to Earth's rotation.
Correct answer is: The day–night cycle affecting irradiance
Q.109 Which of these is a commonly used metric for measuring solar panel performance?
Power density
Temperature coefficient
Heat index
Wind speed
Explanation - Power density (W/m²) quantifies how much power a panel can produce per unit area.
Correct answer is: Power density
Q.110 Which of the following is a characteristic of a 'polycrystalline silicon' panel?
Uniform black color
Grain boundaries in silicon
Single‑crystal structure
Transparent front
Explanation - Polycrystalline panels are made from multiple silicon crystals, showing grain boundaries.
Correct answer is: Grain boundaries in silicon
Q.111 Which of the following is a potential drawback of a 'grid‑parity' solar project?
Higher long‑term operating costs
Lower initial capital outlay
Reliance on local grid reliability
Higher system efficiency
Explanation - If grid reliability is poor, even grid‑parity projects may face outages or service disruptions.
Correct answer is: Reliance on local grid reliability
Q.112 The 'maximum power point (MPP)' of a PV cell can shift due to:
Panel color
Ambient temperature
Panel orientation only
Panel brand
Explanation - Temperature variations change the voltage and current characteristics, shifting the MPP.
Correct answer is: Ambient temperature
Q.113 Which of the following is an example of a 'solar thermal collector'?
Photovoltaic panel
Flat‑plate collector
Battery bank
Inverter
Explanation - Flat‑plate collectors absorb sunlight to heat a fluid for use in heating applications.
Correct answer is: Flat‑plate collector
Q.114 The 'temperature coefficient' of a solar panel is usually expressed as:
W/°C
kWh per day
%/°C
V/°C
Explanation - It indicates the percentage drop in power per degree Celsius increase in temperature.
Correct answer is: %/°C
Q.115 What does 'grid‑connected solar' mean in terms of power flow?
Solar power is stored in batteries only
Solar power is fed to the grid and can be drawn from it
Solar power is isolated from the grid
Solar power is used only at night
Explanation - Grid‑connected systems allow two‑way power flow between the solar array and the utility network.
Correct answer is: Solar power is fed to the grid and can be drawn from it
Q.116 Which of the following is a typical application of solar energy in agriculture?
Solar water pumping
Solar heating of crops
Solar-powered irrigation systems
All of the above
Explanation - Solar power can provide electricity for irrigation pumps, greenhouse heating, and lighting.
Correct answer is: All of the above
Q.117 What is the primary benefit of using a 'battery storage system' with solar panels?
It increases panel temperature
It stores excess electricity for later use
It reduces panel lifespan
It eliminates the need for inverters
Explanation - Battery storage allows you to use solar energy when panels are not producing power.
Correct answer is: It stores excess electricity for later use
Q.118 Which of the following is a common method of maintaining solar panels in dusty environments?
Regular manual cleaning
Applying a dust‑repellent coating
Using high‑pressure water spray
All of the above
Explanation - Cleaning, coatings, and automated systems can all help maintain panel efficiency in dusty areas.
Correct answer is: All of the above
Q.119 In a PV system, the 'short‑circuit current (Isc)' refers to:
Current at maximum power
Maximum current when panel terminals are shorted
Current at zero voltage
Current when panel is fully shaded
Explanation - Isc is the highest current the panel can produce, measured when its output is short‑circuited.
Correct answer is: Maximum current when panel terminals are shorted
Q.120 Which of the following is NOT a factor in determining the cost of a solar PV installation?
Panel efficiency
Local labor rates
Wind speed
Inverter cost
Explanation - Wind speed is unrelated to the cost of a photovoltaic installation.
Correct answer is: Wind speed
Q.121 What is the most common method of securing a solar panel on a roof?
Ballasted mounting
Fixed‑tilt mounting with racking
Direct attachment to shingles
Suction cups
Explanation - Racking systems are the standard approach for rooftop PV installations.
Correct answer is: Fixed‑tilt mounting with racking
Q.122 Which of the following is a key advantage of using perovskite solar cells?
High production cost
Low efficiency
Low manufacturing cost
Inflexibility
Explanation - Perovskite cells can be manufactured at lower cost while achieving high efficiencies.
Correct answer is: Low manufacturing cost
Q.123 Which of these is a major environmental concern associated with solar panel manufacturing?
High water consumption
High CO₂ emissions from panel use
High noise pollution
High fossil fuel use for transportation
Explanation - Manufacturing silicon wafers requires significant amounts of water, posing environmental concerns.
Correct answer is: High water consumption
Q.124 What does a 'solar charge controller' regulate?
AC voltage
Battery voltage and current
Panel temperature
Wind speed
Explanation - The controller ensures batteries are charged safely by controlling voltage and current flow.
Correct answer is: Battery voltage and current
Q.125 What is the primary benefit of using a 'single‑axis tracker' for a solar array?
Lower installation cost
Higher energy yield than fixed‑tilt
Simplicity of design
No mechanical components
Explanation - Single‑axis trackers track the sun’s east–west motion, increasing energy capture over fixed systems.
Correct answer is: Higher energy yield than fixed‑tilt
Q.126 Which of the following describes the 'maximum power point (MPP)' tracking strategy?
It sets a fixed voltage
It maximizes panel temperature
It adjusts load to extract maximum power
It reduces panel shading
Explanation - MPPT algorithms modify the electrical load to keep the PV array at its MPP.
Correct answer is: It adjusts load to extract maximum power
Q.127 What is a common application of solar panels in transportation?
Solar‑powered electric cars
Solar‑powered boats
Solar‑powered airplanes
All of the above
Explanation - Solar panels can provide power for various transport modes, especially in hybrid or off‑grid contexts.
Correct answer is: All of the above
Q.128 Which of the following is a typical benefit of solar energy for communities?
Increased reliance on fossil fuels
Stable and predictable energy costs
High maintenance costs
Limited energy reliability
Explanation - Once installed, solar systems provide relatively low, predictable operating costs.
Correct answer is: Stable and predictable energy costs
Q.129 Which of the following is a type of photovoltaic technology that uses organic materials?
Perovskite
Organic photovoltaic (OPV)
Crystalline silicon
Thin‑film cadmium telluride
Explanation - OPV cells use organic polymers or small molecules as active layers.
Correct answer is: Organic photovoltaic (OPV)
Q.130 Which of the following best describes a 'grid‑parity' solar system?
It is cheaper than grid electricity over the system lifetime
It only works in high‑sunlight regions
It requires no maintenance
It uses only solar panels without inverters
Explanation - Grid parity means solar power costs equal or lower than purchasing from the utility over time.
Correct answer is: It is cheaper than grid electricity over the system lifetime
Q.131 Which of the following is a major benefit of installing solar panels on commercial rooftops?
High operational costs
Reduced property value
Potential tax credits and incentives
Increased reliance on diesel generators
Explanation - Commercial installations often qualify for various tax incentives and rebates.
Correct answer is: Potential tax credits and incentives
Q.132 In solar energy, the term 'shade loss' refers to:
Loss of panel efficiency due to dust
Loss of panel efficiency due to shading
Loss of battery capacity
Loss of inverter efficiency
Explanation - Any obstruction that reduces sunlight reaching a panel causes shade loss.
Correct answer is: Loss of panel efficiency due to shading
Q.133 Which of the following is an example of a 'utility‑scale' solar installation?
A rooftop PV system on a single house
A large solar farm covering several acres
A portable solar charger
A small garden lamp
Explanation - Utility‑scale refers to large, grid‑connected installations that supply significant power.
Correct answer is: A large solar farm covering several acres
Q.134 Which of the following is a typical material used for the backsheet of a solar panel?
Polyethylene terephthalate (PET)
Silicon wafer
Copper
Glass
Explanation - PET backsheets provide moisture protection and structural integrity.
Correct answer is: Polyethylene terephthalate (PET)
Q.135 Which of the following best describes a 'solar tracking system'?
A fixed tilt system
A system that follows the sun’s path to maximize irradiance
A system that stores solar energy in batteries
A system that uses wind energy
Explanation - Tracking systems adjust panel orientation to maintain optimal solar exposure.
Correct answer is: A system that follows the sun’s path to maximize irradiance
Q.136 Which of the following is NOT a benefit of solar PV for businesses?
Lower energy costs
Brand image improvement
Increased reliance on diesel generators
Potential tax incentives
Explanation - Solar reduces dependence on diesel or other fossil fuels.
Correct answer is: Increased reliance on diesel generators
Q.137 Which of these is a major challenge when deploying solar farms in desert regions?
High humidity
Low sunlight intensity
Dust accumulation
Frequent cloud cover
Explanation - Dust reduces panel efficiency if not cleaned, which can be costly in remote desert areas.
Correct answer is: Dust accumulation
Q.138 What is the main advantage of using a 'battery storage system' with solar panels?
It increases panel temperature
It stores excess electricity for later use
It reduces panel lifespan
It eliminates the need for inverters
Explanation - Battery storage allows you to use solar energy when panels are not producing power.
Correct answer is: It stores excess electricity for later use
Q.139 Which of the following is a common method for maintaining solar panels in dusty environments?
Manual cleaning
Use of dust‑repellent coatings
Automated cleaning systems
All of the above
Explanation - Cleaning and coatings help keep panels efficient in dusty climates.
Correct answer is: All of the above
Q.140 In a PV system, what does the 'short‑circuit current (Isc)' represent?
Current at maximum power
Maximum current when panel terminals are shorted
Current when panel is fully shaded
Current at zero voltage
Explanation - Isc is the highest current the panel can produce, measured when the output is short‑circuited.
Correct answer is: Maximum current when panel terminals are shorted
Q.141 Which of the following is NOT a factor in determining the cost of a solar PV installation?
Panel efficiency
Local labor rates
Wind speed
Inverter cost
Explanation - Wind speed is unrelated to the cost of a photovoltaic installation.
Correct answer is: Wind speed
Q.142 What is the typical lifespan of a solar panel?
5–10 years
10–15 years
20–25 years
25–30 years
Explanation - Commercial panels usually guarantee performance for 25 years and often last longer.
Correct answer is: 25–30 years
Q.143 Which of the following best describes a 'smart inverter'?
An inverter that cannot communicate with the grid
An inverter that monitors performance and can communicate with the grid
An inverter that requires manual adjustment
An inverter that only converts DC to AC
Explanation - Smart inverters provide real‑time data and grid support functions.
Correct answer is: An inverter that monitors performance and can communicate with the grid
Q.144 What does 'diel cycle' refer to in solar energy?
The daily cycle of sunrise and sunset
The weekly maintenance schedule
The annual temperature range
The seasonal shift in panel orientation
Explanation - A diel cycle is the day‑night pattern of solar irradiance due to Earth's rotation.
Correct answer is: The daily cycle of sunrise and sunset
Q.145 Which of the following is a commonly used metric for measuring solar panel performance?
Power density
Temperature coefficient
Wind speed
Noise level
Explanation - Power density (W/m²) measures how much power a panel can produce per unit area.
Correct answer is: Power density
Q.146 Which of the following is a characteristic of a 'polycrystalline silicon' panel?
Uniform black color
Single‑crystal structure
Grain boundaries in silicon
Transparent front
Explanation - Polycrystalline panels are made from multiple silicon crystals, showing grain boundaries.
Correct answer is: Grain boundaries in silicon
Q.147 What is the main benefit of a 'grid‑parity' solar project?
Lower long‑term operating costs
Higher initial capital outlay
Reliance on local grid reliability
Higher system efficiency
Explanation - Grid parity means the long‑term cost of solar is lower than conventional grid power.
Correct answer is: Lower long‑term operating costs
Q.148 The 'maximum power point (MPP)' of a PV cell can shift due to:
Panel color
Ambient temperature
Panel orientation only
Panel brand
Explanation - Temperature variations change the voltage and current characteristics, shifting the MPP.
Correct answer is: Ambient temperature
Q.149 Which of the following is a common application of solar thermal collectors?
Photovoltaic panel
Flat‑plate collector
Battery bank
Inverter
Explanation - Flat‑plate collectors absorb sunlight to heat a fluid for use in heating applications.
Correct answer is: Flat‑plate collector
Q.150 The 'temperature coefficient' of a solar panel is usually expressed as:
W/°C
kWh per day
%/°C
V/°C
Explanation - It indicates the percentage drop in power per degree Celsius increase in temperature.
Correct answer is: %/°C