Grade 9 Unit 2 Topic 3 Section C

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In many countries, people produce power from coal, but it is very dirty and causes acid rain. Some countries use nuclear energy to produce power. However, nuclear power can be very dangerous. To solve the energy problem, people all over the world are looking for new ways to produce power.
China is one of the first countries in the world to use biogas technology.
Farmers recycle straw, grass and animal waste to make biogas. This renewable energy is used in people’s everyday lives. Its key disadvantage is that the process requires a long time (up to 30 days) and the cost is high.
Electric vehicles were developed in the 1990s. On April 11, 2010, a new kind of electric vehicle named “Yezi” was shown in the 2010 Shanghai World Expo. It produces electricity from the sun, the wind and CO2. It can not only protect the environment but also save energy. It’s too small to hold many people, but larger models will be developed in the near future.
In China, the best-known maglev train is the German-built one in Shanghai. It takes people just 7 minutes to go to the airport 30 km away. The train can reach a top speed of 431 km per hour. It is quiet and quick. There is no wheel noise because there are no wheels. Maglev trains are very energy-efficient and do not pollute the air. However, maglev guide paths are much more expensive than traditional steel railways.

2a.

The sun, wind, waves and heat from deep in the earth are energy sources.
They will never run out so they arc called renewable sources. In 2011, about 16% of energy used worldwide came from renewable sources. The use of it is increasing rapidly each year.

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