Lesson: Renewable Energy Sources - 2

A. Picture Discussion (Pictures not provided)

Look at the following pictures and discuss what you see in them with your partner. How are the two pictures related?

(Note: Please refer to the pictures provided with your original lesson materials.)

B. Reading

The Benefits of Renewable Energy

Countries worldwide rely heavily on petroleum, coal, and natural gas for their energy. There are two main types of energy sources: renewable and non-renewable. Hydrocarbon or fossil fuels are non-renewable sources of energy. Reliance on them creates serious problems.

First, fossil fuels, such as oil, coal, and gas, are finite—the world will eventually run out of them. Second, they will become very expensive in the coming decades and increasingly damaging to the environment. Third, fossil fuels directly pollute the Earth's environment, contributing to global warming.

In contrast, renewable energy sources, such as wind and solar, are continuously replenished naturally and never run out.

(Picture: A solar panel array)

Most renewable energy comes directly or indirectly from the sun. Sunlight, or solar energy, can heat and light homes, generate electricity, and be used for other commercial and industrial purposes.

The sun’s heat drives the wind, and wind energy can be captured using wind turbines to produce electricity. Both the wind and the sun’s heat cause water to evaporate. When the water vapor turns into rain or snow and flows downhill into rivers or streams, its energy can be captured as hydroelectric energy.

Along with rain and snow, sunlight enables plants to grow. Plants produce biomass, which can be converted into fuels such as firewood and alcohol, categorized as bioenergy.

Scientists have identified hydrogen as another renewable energy source. It is the most abundant element in nature. However, it does not exist independently as a gas. It is always combined with other elements, such as oxygen to form water. Hydrogen, when separated from other elements, can be burned as a fuel to generate electricity.

The Earth’s interior contains molten lava that releases intense heat. This heat inside the Earth produces steam and hot water that can be harnessed as geothermal energy to generate electricity and heat homes.

Ocean energy comes from several sources. The ocean’s tidal and wave forces can be used to produce energy. The surface of the ocean receives more heat from the sun than the ocean depths. This temperature difference can also be used as an energy source.

(Source: the Internet)

Questions:

1. What are renewable energy sources?
2. What are the problems associated with non-renewable energy sources?
3. What are the main differences between renewable and non-renewable energy sources?

C. Renewable Energy in Bangladesh

Which renewable energy sources mentioned in the text have you heard of before? One of these resources is used in the Chittagong Hill Tracts (CHT) to produce electricity. Can you name it?

Browse the internet in groups to research the answers to the following questions and present your findings to the class.

1. What is the name of the project?
2. Where in the CHT is the project located?
3. When did it start operating?
4. How much electricity does it produce for the national grid?
5. How many units are operating there?
6. What is the positive impact of the project on national development?

D. Dialogue and Comprehension

Read the dialogue between Raju, a student in Class 10, and his uncle, Mr. Barua, who works at the Sangu Gas Field. Then answer the following questions:

Mr. Barua: What are you reading, Raju?

Raju: English, Uncle. A chapter on renewable energy sources.

Mr. Barua: I see. Do you know that renewable energy is also called green energy?

Raju: Green energy…? No, Uncle, I don’t know. There’s nothing about green energy in the text either.

Mr. Barua: Are you sure? Renewable energy sources provide us with energy that doesn’t harm the environment during production or consumption. Take solar energy, for example. You see, there’s no burning, no smoke, no emission of gases. It’s a kind of clean technology and a clean energy source.

Raju: Oh, that’s right. That’s what our teacher said, I remember.

Mr. Barua: On the other hand, burning fossil fuels, like oil or coal, emits greenhouse gases that harm the environment.

Raju: Oh… I see. Yes, I get it now, Uncle. Thanks a lot. I understand the connection between the two pictures in Section A. Green energy sources make a green globe. Excellent!

(Note: Refer to pictures in Section A of your original lesson materials.)

Questions:

1. Why is renewable energy called green energy?
2. “Nothing is there about green energy in the text either.” – Do you think Raju’s statement is correct? Explain why/why not.
3. “I now understand the relation between the two pictures in section A.” What does Raju mean here? What does he understand? Do you agree with Raju’s viewpoint? Why?

E. Dialogue Completion and Role Play

Read the following dialogue and then act it out in pairs:

A: What is solar energy?

B: It’s one of the renewable energy sources.

A: Why is it called green energy?

B: It’s called green energy because it helps us keep the Earth green. It doesn’t emit any pollutants into the atmosphere when we produce and use it.

A: I see. Then it must be a clean source of energy.

B: Exactly. And that’s why it’s also called clean energy.

Now complete the following dialogue using the model above:

A: What is wind energy?

B: It’s one of the ______.

A: Why is it called ______?

B: Well, it’s green energy because ______ the Earth green. It doesn’t ______ when we produce and use it.

A: I see. Then it ______ source of energy.

B: Exactly. And that’s why ______ clean energy.

F. Dialogue Writing

Now write dialogues about hydroelectricity, ocean energy, geothermal energy, and hydrogen energy using the model in Section E above.

G. Letter Writing

Both South and North Dhaka City Corporation are installing solar panels to illuminate roads in many areas instead of conventional electricity connections. Write a letter to the editor of a daily newspaper expressing your appreciation for this initiative. Explain why other city authorities should follow their lead.