What is the primary role of an inverter in a PV system? | Agrigyan

• Primary Function of a Solar Still:
• Solar Desalination: A solar still is a passive solar distillation device designed to produce potable fresh drinking water from brackish groundwater, seawater, or contaminated wastewater.
• Thermodynamic Process: Incident solar radiation penetrates a transparent sloped glass cover to heat a shallow basin of saline water. Water evaporates, condenses upon the cooler underside of the tilted glass pane as pure distilled water, and trickles down into collection gutters leaving salts, heavy metals, and microbes behind in the basin.
• Conclusion: To desalinate water (Option 3).

Correct option: (3) To desalinate water

• Electrical Load Estimation for Solar PV Systems:
• Sizing electrical loads for a photovoltaic power system strictly requires:
• Power rating of connected loads (watts) and daily duty cycle (hours/day) to compute total daily energy demand (watt-hours/day).
• Peak Sun Hours (PSH) available at the installation site.
• Overall system efficiency (including inverter, wiring, and charge controller losses).
• Battery storage capacity and days of autonomy for stand-alone setups.
• Wind Speed: An aerodynamic structural parameter for mechanical mounting design or wind turbine siting, but is not considered in electrical PV load estimation.
• Conclusion: Wind speed (Option 4).

Correct option: (4) Wind speed

• Moisture Removal Mechanism in Solar Dryers:
• Physical Mechanism: In active and passive solar agricultural dryers, heated air flows over the moist agricultural produce, transferring sensible heat to the food surface.
• Evaporation: The absorbed thermal energy provides the latent heat of vaporization ($L_v \approx 2.4\text{ MJ/kg}$), transforming bound and free liquid moisture into water vapor, which diffuses across the boundary layer and is carried away by convective airflow (Evaporation).
• Other Terms:
• Condensation: Phase change from vapor to liquid.
• Sublimation: Phase change from solid directly to vapor (used in freeze-drying).
• Conclusion: Evaporation (Option 2).

Correct option: (2) Evaporation