JNTU B.Tech IV NON-CONVENTIONAL SOURCES OF ENERGY Previous Question Paper (July/August - 2022 - R18)

Renewable energy sources play a critical role in achieving energy security, reducing environmental degradation, and fostering sustainable economic development. Their primary function is to provide a continuous, inexhaustible supply of power that mitigates the reliance on finite fossil fuels, which are the leading contributors to greenhouse gas emissions and climate change.

The potential of these sources is vast, particularly in regions with high solar irradiance, wind corridors, or significant biomass availability. Key aspects of their potential include:

• Decentralization: Renewable systems allow for off-grid power generation, providing electricity to remote and rural areas where grid extension is economically unfeasible.
• Environmental Impact: They offer a pathway to decarbonize the energy sector, significantly lowering carbon footprints and air pollution levels.
• Economic Growth: The transition to renewables creates new industries, promotes technological innovation, and generates employment in manufacturing, installation, and maintenance sectors.
• Energy Security: By utilizing indigenous resources, nations can reduce their dependence on imported fuels, insulating their economies from global price volatility.

A flat plate collector is the central component of solar thermal systems, designed to absorb solar radiation and transfer it as heat to a working fluid. Its primary components and their functions are:

• Absorber Plate: Usually made of high-thermal-conductivity metal like copper or aluminum, it is coated with a selective surface to maximize solar absorption and minimize infrared re-radiation. It converts solar energy into thermal energy.
• Tubes/Channels: These are attached to or integrated into the absorber plate. The working fluid (water or air) flows through these tubes, absorbing the heat conducted from the absorber plate.
• Glazing (Cover Plate): Typically made of tempered low-iron glass, it allows short-wave solar radiation to enter while trapping long-wave thermal radiation emitted by the absorber plate, creating a greenhouse effect to reduce heat loss.
• Insulation: Placed at the back and sides of the collector (often using glass wool or polyurethane), it minimizes conductive and convective heat losses to the surroundings, ensuring maximum heat transfer to the fluid.
• Casing/Box: A rigid frame that holds all components together, protects them from environmental factors, and provides structural integrity to the assembly.