TOPIC: Energy AIM: 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 energy 2. Lubricants (grease, motor oil)

3. Plastics 4. Synthetic fibers 5. 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 fuel Creates more pollution than other fossil fuels

90% of coal used is burned to generate electricity

5. Nuclear Energy Energy found in the nuclei of atoms Power 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 scarce 2.Power plants need less fuel than ones which burn fossil fuels

3. Do not produce air pollutants & CO 2

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: Energy AIM: 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. Wind Wind turbines use wind energy to pump water and are connected to an electric generator

2. Solar energy The 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 water Hydroelectricity 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 matter Example: 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.