Energy is needed for living things as well as for machines.
Fossil fuels are now used to get most of the energy used by man. Fossil fuels such as oil, coal and natural gas , have been formed from the remains of plants and animals that were buried beneath layers of earth and rocks for millions of years. Fossil fuels are non-renewable fuels because they will run out one day.
Renewable Sources of Energy never run out. Examples of these sources are : The wind
It has been used for centuries to sail ships and to pump water. Nowadays, it is used to make electricity. For instance, wind farms along the Red Sea are connected to turbines to generate electricity. Water
Hydro-electric power is generated from waterfalls. For example, the electricity that is generated from the falling water in the Aswan High Dam forms 16% of Egypts electricity. Atomic or Nuclear power
It is generated from the splitting or joining of atoms together. Its disadvantages lie in the dangerous wastes left and in the bad management of atomic power stations that result in sending up atomic dust killing plants, animals and causing diseases to humans. This happened at Chernobyl in 1986. The sun
The suns energy is essential to living things to make their food from the soil and the air. We get energy by eating plants or meat from animals that eat plants. The suns energy is also used to get electricity or heat. How we can save energy
We should turn the light off when we have to leave a room.
TV or computers should be switched off when we have finished using them. Recycled materials should be used . Glass, paper and m*etal, for example, should be reused instead of throwing them away. Lesson 4
The interviewer asks Dr Zeinab about geothermal energy. She says rocks far below the surface of the earth are molten. The earths heat warms underground pools of water and may produce steam. We have a hot spring of water if theres an opening in the Earth.
In the Siwa Oasis we have warm water that comes up to the Earth.
Modern technology helps to drill deep below the surface of the Earth.
Hot underground water is pumped and heated to produce steam which is sent to a power station through pipes connected to turbines to produce electricity. Lesson 5
Scientists are now working on ways to use solar power for vehicles.
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Solar-powered vehicles have batteries that run out quickly and need a long time to recharge them.
Students at Dovedale High School entered an international solar bike race.
They raised money by selling T-shirts and getting help from local companies.
While they were building the bike, the bike rider was training.
The race had 13 laps then a break to recharge the batteries then 12 more laps each was 4 km long.
They were pleased to finish second in the race.