Case Study:

India is rapidly expanding its renewable energy sector to reduce dependence on fossil fuels and decrease pollution. Solar energy plants are becoming an important part of this transition. In a solar power plant, photovoltaic PV panels convert sunlight directly into electrical energy.

For example, a solar power plant in India with a capacity of 67.2 MW can supply electricity to around 1,26,000 people using more than 2,00,000 solar modules installed over large land areas. 

Another important fact about solar plants is their electricity generation capacity. Under normal sunlight conditions, a 1 MW solar power plant can produce about 4,000 units of electricity per day, which equals roughly 14.4 lakh units annually. 

In a typical solar plant, thousands of solar panels are arranged in rows. Each panel contains photovoltaic cells made of semiconductor materials such as silicon. When sunlight falls on these cells, electrons are released, creating an electric current. This electricity is then converted from direct current DC to alternating current AC using inverters before being supplied to homes and industries.

Solar power plants have several advantages. They produce electricity without burning fuels, reduce greenhouse gas emissions, and help conserve non-renewable energy resources like coal and petroleum. However, solar plants require large land areas and their energy production depends on sunlight availability.

The Indian government is encouraging solar energy projects through initiatives and solar parks to promote clean and sustainable electricity generation. Such projects are essential for meeting future energy demands while protecting the environment.

Questions:

Section A - MCQs

1. A 1 MW solar power plant produces about 4,000 units of electricity daily. If a town requires 8,000 units per day, how many such plants are needed?
   A. 1
   B. 2
   C. 3
   D. 4
2. Which component converts DC electricity from solar panels into AC electricity used in homes?
   A. Turbine
   B. Inverter
   C. Transformer
   D. Generator
3. The main environmental advantage of solar energy plants is that they:
   A. Use coal as fuel
   B. Produce electricity without air pollution
   C. Generate nuclear radiation
   D. Consume large amounts of water
4. If a solar plant generates 1,20,000 units of electricity per month, what is its approximate yearly generation?
   A. 1,20,000 units
   B. 6,00,000 units
   C. 14,40,000 units
   D. 24,00,000 units

Section B - Short Answer Questions

1. Explain how photovoltaic cells convert sunlight into electrical energy.
2. Why is solar energy considered a renewable and sustainable source of energy?
3. Identify one limitation of solar power plants and suggest a possible solution.

Section C - Long Answer Question

A district plans to install a 5 MW solar power plant to supply electricity to nearby villages.

Using the data that 1 MW produces about 4,000 units per day, answer the following:

1. Calculate the total electricity produced by the 5 MW plant per day.
2. Explain how installing such plants can help reduce fossil fuel consumption.
3. Suggest two additional renewable energy sources that could be used with solar energy.

Answer Key:

MCQ Answers:

1. B
2. B
3. B
4. C

Short Answers:

1. Photovoltaic cells contain semiconductor materials like silicon. When sunlight falls on the cell, photons release electrons, creating a flow of electric current which produces electricity.
2. Solar energy is renewable because sunlight is continuously available and does not get exhausted. It is sustainable since it produces electricity without releasing harmful gases or pollution.
3. Limitation: Solar plants depend on sunlight and cannot produce electricity at night.
   Solution: Use battery storage systems or combine solar power with other renewable sources.

Long Answer:

1. Electricity generation calculation
   Daily units from 1 MW = 4,000 units
   For 5 MW = 5 × 4,000
   = 20,000 units per day
2. Solar plants generate electricity without burning coal or oil. Therefore, installing them reduces the use of fossil fuels and lowers carbon emissions.
3. Two additional renewable energy sources:

• Wind energy
• Hydroelectric power