Presentation on theme: " The sun constantly gives off energy in the form of light and heat. Earth receives enough solar energy to meet the energy needs of the entire world."— Presentation transcript:
The sun constantly gives off energy in the form of light and heat. Earth receives enough solar energy to meet the energy needs of the entire world for 40 years. Advantages: 1. It does not cause pollution 2. Abundant availability, It will not. Disadvantages: 1. Its only available when the sun is out and it is very spread out.
Solar Plants: Rows of giant mirrors focus the sun’s rays to heat a tank of water. The water boils, making steam that is used to generate electricity. Solar Cells: consists of a “sandwich” of very thin layers of the element silicon and other materials.
Hydroelectric power is electricity produced by flowing water. It is the most widely used source of renewable energy in the world today. Advantages: 1. It is inexpensive. 2. No pollutions 3. Provides a steady supply of energy.
Tides are another source of moving water. The gravity of the moon and sun causes the water on Earth’s surface to rise and fall on its shores. A few tidal power plants have been built to take advantage of this regular motion.
The oldest fuel used for heat and light is wood. Other biomass fuels are leaves, food, wastes and manure. Biomass materials can be converted into other fuels; 1. Gasohol-corn makes alcohol, add alcohol to gasoline produces fuel for cars. 2. Bacteria decomposes turns into methane gas is used to heat buildings.
Intense heat from Earth’s interior. Geothermal energy is an unlimited source of cheap energy. Disadvantages: 1. Only a few places where magma comes close to Earths surface. (Iceland) 2. Need to drill deeper wells (expensive)
Energy of the future: 1. Burns cleanly 2. Water is its only by-product 3. It creates no smog, smoke or acid rain. 4. Can be handled and transported through pipelines. 5. Exists on Earth in large supply. Disadvantage: Almost all of Hydrogen is combined to Oxygen