TOPIC: Energy
AIM: Describe the various sources of
energy that exist on Earth.
Do Now:
http://www.brainpop.com/science/energ
y/formsofenergy/
HW: Work on your atom drawing/model.
Due on Friday!!!!!
Which skier will
have a greater
potential
energy? Support
your answer.
Which of the following increases when a metal
spring is stretched horizontally?
1. Potential energy
2. Kinetic energy
3. Gravitational potential energy
4. Electrical energy
Identify the form of energy being described.
1. Windmills
2. Food
3. Moving roller coaster
4. Created as a result of Friction
5. Gasoline
6. Created by light bulbs
7. A moving car
8. Batteries
9. Lightening
10.Found in the nucleus of an atom
11.Sunlight
A family is moving from Pennsylvania to
Connecticut. As the moving van burns gasoline, it
converts
1. chemical energy into mechanical energy
2. kinetic energy into potential energy
3. thermal energy into electrical energy
4. mechanical energy into kinetic energy
Which device produces mechanical
energy?
1. A battery
2. A light bulb
3. An electric motor
4. A solar cooker
A song is playing on the radio. Which
best describes the change in the flow of
energy?
1. Electrical energy  light energy
2. Electrical energy  sound energy
3. Sound energy  light energy
4. Sound energy electrical energy
Remember the Law of
Conservation of Energy:
Energy can’t be created
nor destroyed, just
changed from 1 form to
another
Major
• The
source of
Energy
on earth
sun
Nonrenewable
Energy
Resources
• 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 =
Examples of
Nonrenewable formed from
Energy
remains of ancient
Resources
plants & animals
• Release carbon dioxide
(global warming)
2.Petroleum: liquid, highly
flammable
• Formed from plant remains
• Used to produce:
- Oil (burned to produce energy)
- Lubricants (grease, motor oil)
- Plastics
- Synthetic fibers
- Asphalt
3.Natural Gas: Burned to
provide energy for cooking,
heating…
• Burns more cleanly than other
fossil fuels
4. Coal: solid fossil fuel
• 90% of coal used is burned to
generate electricity
• Creates more pollution
5. Nuclear Energy: found in the
nuclei of atoms
• Power plants convert this to
electrical energy
• Use the process of FISSION
(nucleus of atom breaks
apart)
Advantages • Power plants could
of nuclear still produce
energy
electricity after coal
and oil become
scarce
• Power plants need less fuel
than ones which burn fossil
fuels.
(One ton of uranium produces more
energy than is produced by several
million tons of coal or several
million barrels of oil)
• Do not produce air pollutants &
CO2
• Nuclear explosions
Disadvantages produce radiation.
of nuclear
– harms body cells 
illness or death
energy
– Reactor disaster =
meltdown.
• Fission reaction goes
out of control 
nuclear explosion
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.
• Water used to cool power plants
– excess heat may kill organisms in
streams & rivers it’s released into
• Wastes release radiation
– Cannot be thrown away like garbage
– Stored in special cooling pools at the
nuclear reactors
TOPIC: Energy
AIM: Describe the various sources of
energy that exist on Earth.
Do Now: Describe some examples of
nonrenewable resources.
http://www.brainpop.com/technology/energytechnology/fossilfuels/
HW: Work on your atom drawing/model.
Due tomorrow!!!!!
Renewable • Energy sources that
can be replaced as
Energy
Resources quickly as it is used
• Will be around for
millions of years
Examples of
renewable
Energy
resources
1.Wind: windmills use
wind energy to pump
water
– Connected to electric
generator
http://www.youtube.com/watch?v=tsZITSeQFR0
• No pollution
• Low costs
• But if there is no wind  no
energy
2.Solar energy: more expensive
than using fossil fuels
http://www.youtube.com/watch?v=x4CTceusK9I
3. Moving water (Hydroelectricity):
Electricity produced from energy of
moving water
http://www.youtube.com/watch?v=fvYaCtjpMvk
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
http://www.youtube.com/watch?v=-ajqiPe_9Ko
5. Biomass: renewable organic
matter
• Example: wood, garbage, crops
http://www.youtube.com/watch?v=sN68ef6trEs
http://www.youtube.com/watch?v=Euz9DSYTxUo
Biogas is one of the most popular
sources of renewable energy. It is
derived from organic sources.
Biogas generation is the process
for producing biogas from organic
matter. It is a good resource to make
farms be independent as biogas can
be used for electricity generation.
Compressed biogas can also be
used as an alternative vehicle fuel. It
is a colorless, odorless, inflammable
gas. It comprises of methane and
carbon dioxide. Biogas is produced
when organic matter is broken down
by anaerobic bacteria. Bio energy is
a major player in sustainable living in
countries like India and China where
individual biogas generators have
been developed in villages to make
them self-sufficient in terms of power
generation.
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.
Let’s summarize…
1. What is the earth’s main source of energy?
2. Describe nonrenewable resources and give
some examples.
3. Describe some advantages and disadvantages
of nuclear energy.
4. Describe renewable resources and give some
examples.
Let’s summarize…
1. Explain the difference between renewable and
nonrenewable resources.