Natural Resources

• A natural resource is a feature of Earth that benefits people.

• Earth’s natural material resources are things like air, fresh water, and soil.

16.2 Electricity from fossil fuels• A nonrenewable resource is not replaced as

it is used.

• Because it takes so long for these resources to form, someday we will not have enough fossil fuels to produce the electricity we need.

• The three major fossil fuels are coal, oil, and natural gas.

Video clip on fossil fuels

COAL, PETROLEUM, AND GASCoal, petroleum, and natural gas are

considered nonrenewable

because they can not be replenished in a

short period of time. These are called

fossil fuels. Video clip on fossil fuels

Video clip on reliance on fossil fuels

HOW IS COAL MADE ???

HOW ARE OIL AND GAS MADE ???

Electricity from renewable resources (often called alternative energy sources)

• A renewable resource can be replaced naturally in a relatively short period of time.

• The Sun and wind are renewable resources that can be used as energy sources.

Electricity from renewable resources

• It is also possible to use:

– moving water (hydroelectric)

– hot spots near Earth’s surface (geothermal)

– Energy from plant material (biomass)

– Let’s look at some of these!

Energy released by fission (or fusion) reaction.

This is steam, not polluted air!

Video clip on nuclear power

•Nuclear power costs about the same as coal, so it's not expensive to make.

•Does not produce smoke or carbon dioxide, so it does not contribute to the greenhouse effect.

•Produces huge amounts of energy fromsmall amounts of fuel.

•Nuclear power is reliable.

- Although not much waste is produced, it is very, very dangerous. It must be sealed up and buried for many years to the radioactivity to die away.

- Nuclear power is reliable, but a lot of money has to be spent on safety . If it does go wrong, a nuclear accident can be a major disaster.

Buford Dam at Lake Lanier

Buford Dam at Lake Lanier

Video clip on Hydroelectric power

- Once the dam is built, the energy is free. - No waste or pollution produced.

- Much more reliable than wind, or solar power.

- Water can be stored above the dam ready to cope with peaks in demand.

- Electricity can be generated constantly.

-The dams are very expensive to build. However, many dams are also used for flood control or irrigation, so building costs can be shared.

- Building a large dam will flood a very large area upstream, causing problems for animals that used to live there.

- Finding a suitable site can be difficult – the impact on residents and the environment may be unacceptable.

Windmills are built together in a “wind farm.”

The use of a windmill to drive an electric generator.

Video clip about Wind power

                                                                     

How good an area for wind power is GA?

•Wind is free, wind farms need no fuel. •Produces no waste or greenhouse gases.

•The land beneath can usually still be used for farming.

•Wind farms can be tourist attractions. •

A good method of supplying energy to remote areas.

•The wind is not always predictable – some days have no wind.

•Suitable areas for wind farms are often near the coast, where land is expensive.

Noisy. A wind generator makes a constant, low, "swooshing" noise day and night. An entire wind farm makes quite a racket!

•Can kill birds - migrating flocks tend to like strong winds. Splat!

Several ways to use the sun for power!

The energy received by Earth from the sun in the form of radiation.

Solar cells to make electricity like your solar calculator does.

Info on picture

Solar power plants that can produce large amounts of electricity instead

of for one house.

Places where solar power plants would work!

We even use solar power in orbit! Why would that be a good way to

power satellites?

Video clip on solar power

•Solar energy is free - it needs no fuel and producesno waste or pollution.

•In sunny countries, solar power can be used where there is no easy way to getelectricity to a remote place.

Doesn't work at night.

Very expensive to build solar power stations.

Solar cells cost a lot to make.

Can be unreliable unless you're in a very sunny climate.

The energy produced by heat within the Earth.

Sometimes it is very close to the surface.

Video clip on geothermal energy

What do you think would be the advantages and disadvantages of geothermal energy?

Biomass is the second most common form of renewable energy.

What do you think would be the advantages and disadvantages of biomass energy?

Short video review of energy

•Use them only when necessary.•Take care of them even when you are not using them.

SoilSoil Conservation Conservation

n any method to maintain the fertility of the soil by protecting it. erosion

Soil Conservation Techniques

• Contour Plowing: farmers plow across the slope of hills to prevent erosion.

• Terracing: changes one steep hill into a series of smaller, flatter fields.

• Crop Rotation: farmers rotate the crops in their fields to use either less, or different nutrients from the soil.

• No-till farming: is the practice of leaving old stalks on the field instead of picking them up. It provides cover from the rain, and prevents erosion.