Alternative Energy Sources How is your electricity generated? Steps - - PowerPoint PPT Presentation

Alternative Energy Sources

How is your electricity generated?

Steps to generating electricity:

• 1. Heat is created
• 2. The heat boils water, which creates

steam

• 3. The steam builds pressure in pipes
• 4. The pressure turns turbine blades
• 5. When the turbines spin, so does a

generator

• 6. When the generator spins,

electricity is created

• 7. The steam cools back into water

What is wrong with this?

How is your electricity generated?

• Coal and natural gas make 67% of the electricity

used in our country

• TEP (Tucson Electric Power) stopped using coal

toward the end of 2015 in favor of natural gas

• There is a finite amount of coal, natural gas, and oil

This leaves people with two choices:

• 2. Find other sources of energy so we can keep having

electricity

• 1. Use less electricity as resources are depleted

and accept that, eventually, there will not be any more fuel

Forms Of Alternative Energy

• Nuclear
• Photovoltaic (solar)
• Wind
• Hydropower
• Biopower
• Geothermal
• Ocean

Nuclear Power

• 1. Heat is created by a nuclear reaction
• 2. The heat boils water, which creates

steam

• 3. The steam builds pressure in pipes
• 4. The pressure turns turbine blades
• 5. When the turbines spin, so does a

generator

• 6. When the generator spins, electricity

is created

• 7. The steam cools back into water

19% of our nation’s energy comes from nuclear power

Nuclear Power – Pros and Cons

Advantages 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 from small amounts of fuel. Produces small amounts of waste. Nuclear power is reliable. Disadvantages Although not much waste is produced, it is very, very dangerous. The waste must be sealed up and buried for many years to allow the radioactivity to die away. For all that time it must be kept safe from earthquakes, flooding, terrorists and everything else. This is difficult. 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 catastrophic

Photovoltaic (Solar) Power

• 1. Sunlight trapped by glass
• 2. Electrons are bumped from one layer of

silicon to another

• 3. Movement of electrons is called electricity

.4% of our nation’s energy comes from solar power 5% of Arizona’s power comes from solar power

Solar Power – Pros and Cons

Advantages Low maintenance cost Does not produce smoke or carbon dioxide, so it does not contribute to the greenhouse effect. No fuel needed Panels good for 25 years Disadvantages High cost up front Cloudy days, nights don’t produce much electricity Panels are not very efficient (12% – 30%)

Wind Power

4.4% of our nation’s energy comes from wind power

• 1. Wind blows over the blades,

causing them to turn

• 2. They are connected to a shaft

that turns a turbine

• 3. The turbine turns a generator
• 4. Electricity comes from the

generator

Wind Power

2700 windmills in Palm Springs 65 ft tall Blades are 15 ft long

Wind – Pros and Cons

Advantages Multiple windmills can be turned by the same wind No waste. They don’t take up much land so they can be placed in small areas Disadvantages No wind = no electricity Start up and maintenance costs Aesthetics

Hydroelectric Power

6% of our nation’s energy comes from hydroelectric power

• 1. Water flows up high to down

low (potential to kinetic energy)

• 2. Flowing water turn a turbine
• 3. The turbine turns a generator
• 4. Water keeps flowing down a

river

Hydroelectric Power – Pros and Cons

Advantages The river never stops flowing Produces no waste Capable of producing large amounts of electricity Disadvantages Need a river Droughts Environmental affects of a dam Cost of building a dam

Biopower (Biomass)

1.7% of our nation’s energy comes from bio power Waste from plants or animals can be used Examples: Biofuel – diesel, ethanol Methane gas

Biopower – Pros and Cons

Advantages Organic waste is very common Organic waste is very inexpensive Disadvantages Produces small amounts of electricity

Geothermal Power

.4% of our nation’s energy comes from geothermal power

• 1. Hot water from underground

flows up under its own pressure

• 2. Water turns into steam
• 3. The steam turns a turbine to

make electricity

• 4. The steam is then cooled and the

water goes back

Geothermal Power – Pros and Cons

Advantages Heat from underground is all everywhere No waste Disadvantages Does not produce large amounts of electricity

Ocean Power – Option 1

The ocean surface is warmed by the sun; deeper water is cold A working fluid is:

• 1. Warmed by the surface water
• 2. Turned into steam
• 3. The steam spins a turbine to

make electricity

• 4. The steam is then cooled and the

cycle starts over

Ocean Power – Option 2

• 1. Buoy is moved up and down by

swells

• 2. Fluid is pumped to spin a turbine
• 3. The turbine spins generator to

make electricity

Ocean Power – Option 3

As the tide comes in, or goes out, it spins a turbine that is underwater. This spins a generator to create electricity.

Ocean Power – Pros and Cons

Advantages 70% of the Earth is covered in ocean Ocean water retains heat well Waves and tides never turn off Disadvantages Not everybody lives near an ocean Tides and waves are not consistent in strength Salt water accelerates corrosion of metals

What Should We Do?

In the blank space on the back of your packet, write a paragraph explaining what you think we should do if we were to abandon the use

• f fossil fuels to produce electricity and explain why.

References

https://www.eia.gov/tools/faqs/faq.cfm?id=427&t=3