topic: energy aim: how does the earth supply us with energy? do now: complete worksheet titled...
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TOPIC: EnergyAIM: How does the Earth supply us with Energy?
DO NOW: Complete worksheet titled
“Energy”
Remember the Law of Conservation of Energy????:Energy can’t be created nor destroyed, just changed from one form to another
The sun
Major source of Energy on earth
• Resources that can’t be replaced by natural processes as quickly as they are used
• Takes millions of years for nature to reproduce
1. Fossil fuels formed from remains of ancient plants & animals
Example of fossil fuels include: Coal, natural gas, petroleum, oil
When Fossil Fuels are burned they release carbon dioxide which is the main contributor to global warming
2. Petroleum
• Liquid, highly flammable• Formed from plant remains• Mixture of hydrocarbons
(contain H & C)
Used to produce: 1. Oil = burned to produce energy2. Lubricants (grease, motor oil)
3. Plastics4. Synthetic fibers5. Asphalt
3. Natural Gas
Made of methane & hydrocarbon gases (like propane)
Burned to provide energy for cooking, heating…
Supplies ¼ of energy used in US
Burns most clean of all of the fossil fuels
4. Coal
Solid fossil fuelCreates more pollution than other fossil fuels
90% of coal used is burned to generate electricity
5. Nuclear Energy
Energy found in the nuclei of atomsPower plants convert this to
electrical energy
Use a process called FISSION
Generates almost 20% of electricity in US
Produce 80% of all energy consumed in the US
Advantages:1.Power plants could still produce electricity
after coal and oil become scarce2.Power plants need less fuel than ones
which burn fossil fuels
3. Do not produce air pollutants & CO2
Disadvantages:1. Nuclear explosions produce radiation.
It harms cells of the body that results in illness or death
Reactor disaster = meltdown. Fission reaction goes out of control which causes a nuclear explosion & release of a lot of radiation.
Chernobyl, Ukraine, 1986 reactor core overheated during safety test. Materials in the core caught fire and caused a chemical explosion that blew a hole into the reactor. Radiation was carried by the wind. Twenty-eight people died of radiation sickness.
2. Water used to cool power plants which creates excess heat that may kill organisms in the streams & rivers it’s released into
3. Wastes release radiation which cannot be thrown away like our garbage. Stored in special cooling pools at the nuclear reactors.
TOPIC: EnergyAIM: How does the Earth supply us with Energy? Part 2
DO NOW:Compelete worksheet
“Energy Sources”
• Energy sources that can be replaced as quickly as it is used
• Will be around for millions of years
1. WindWind turbines use wind
energy to pump water and are connected to an electric generator
2. Solar energyThe amount of solar energy that falls on
US in 1 day is more than the total amount of energy used in US in 1 year
More expensive than using fossil fuels
3. Moving waterHydroelectricity is
electricity that is produced from energy of moving water
Produces 8% of electrical energy in US
These use the GPE of water on hills to generate electricity as it flows downhill.
Tidal Power.
4. Geothermal energy Heat from earth’s interior (magma)Used to generate electricity
5. Biomass Renewable organic matterExample: wood
Ethanol = clear, colorless alcohol fuel made from the sugars found in grains, such as corn & wheat, and potato skins & rice. It is renewable because it is made from plants. To make ethanol we use yeast to ferment the sugars and starch in corn. Corn is the main ingredient for ethanol in the US due to its abundance and low price. The starch is fermented into sugar fermented into alcohol. Other crops such as, barley, wheat, rice, sorghum, sunflower, potatoes, sugar cane and sugar beets can also be used to produce ethanol.