What does the passage primarily discuss?

Câu hỏi :

Read the text and choose the best answer to the following questions by circling A, B, C or D.

Solar energy is a long lasting source of energy which can be used almost anywhere. To generate solar energy, we only need solar panels and the sun! Solar panels can easily be installed on house roofs, so no new space is needed and each user can quietly generate their own energy. Compared to other renewable sources, they also possess many advantages. Wind and water power rely on turbines which are noisy, expensive and easy to break down. Solar panels are totally silent and non-polluting. As they have no moving parts, they require little maintenance and have a long lifetime.

However, solar energy also has some disadvantages. We can only generate solar energy during daytime because the system depends on sunlight. Besides, solar panels require large area to work effectively. The main disadvantage of solar energy is that it costs about twice as much as traditional sources such as coal, oil, and gas. This is because solar panels are expensive.