ENERGY
• Energy is the capacity to do work.
• Potential and kinetic energy are
considered types of energy.
• Kinetic energy is the energy of motion.
• Potential energy is the energy
associated with forces that depend on
the position or configuration of a body
and the surroundings.
• A renewable energy source is
considered a permanent energy
source, that can be replenished as it
is used (such as solar, wind, tidal). A
non-renewable energy source is
considered to be a temporary
source; one which is depleted as it
is used such as coal, oil and natural
gas.
ENERGY SOURCES
Characteristics of Energy
Sources
• According to the second law of
thermodynamics, whenever energy is used,
some is always lost into the environment as a
less useful form of energy. In order for energy
sources to be useful, these must involve
processes which move towards lower energy
states and release energy at reasonable rates
(neither too fast nor too slow).
•They should be easily
accessible.
•If possible, their use should be
harmless to the environment.
•They should be cheap and
plentiful.
Current and Potential Energy
Source
• chemical energy
• electric power
• fossil fuels
• nuclear energy
• solar energy
• wind energy
•geothermal energy
• biomass energy
• hydropower energy
• ocean energy
• tidal energy
Chemical Energy
Chemical energy is released during
a chemical reaction. Chemical
energy can also be converted to
electrical energy in electrochemical
cells (batteries) and fuel cells.
Electric Power
Most of the world are becoming increasingly
electrified. Today, more than half of the
electricity generated in the world comes from
coal. For the foreseeable future, coal will
continue to be the dominant fuel used for
electric power production. The low cost and
abundance of coal is one of the primary
reasons why consumers in the world benefit
from some of the lowest electricity rates of any
free-market economy.
Fossil Fuels
Fossil fuels – coal, oil and natural gas -currently provide more than 40% of all the
energy consumed in the world, nearly twothirds of the electricity, and virtually all of the
transportation fuels. Moreover, it is likely that
the nation’s reliance on fossil fuels to power
an expanding economy will actually increase
over at least the next two decades even with
aggressive development and deployment of
new renewable and nuclear technologies.
Coal
Coal is one of the true measures of the
energy strength of the world. One quarter
of the world’s coal reserves are found within
the United States, and the energy content of
the nation’s coal resources exceeds that of
all the world’s known recoverable oil. Coal
is also the workhorse of the nation’s electric
power industry.
Petroleum is a thick, dark liquid
composed mostly of compounds called
hydrocarbons that contain carbon and
hydrogen.
Natural Gas, usually associated with
petroleum deposits, consists mostly of
methane, but it also contains significant
amounts of ethane, propane and
butane.
Nuclear Energy
Nuclear Energy is produced either by
splitting (fission) or combining (fusion) of
atoms.
Fission: Splitting a heavy nucleus into
two nuclei with smaller mass numbers.
Fusion: Combining two light nuclei to
form a heavier, more stable nucleus.
In the last three decades, nuclear
power has played a significant role in
electricity generation. Currently nuclear
power supplies more than 10% of the
world’s total electricity. It produces little
pollution and virtually no greenhouse
gases. Well-designed, constructed and
operated nuclear power plants have
proven to be reliable, safe, economical
and environmentally benign.
Solar Energy
Developing technologies that take advantage
of the clean abundant energy of the sun is
important to reducing greenhouse gasses
and helps stimulate the economy. Examples
of solar technologies are Photovoltaic cells,
concentrating solar power technologies and
low temperature solar collectors.
Photovoltaic cells convert sunlight directly into electricity.
Photovoltaic cells provide tiny amounts of power for
watches, large amounts for the electric grid, and everything
in between.
Concentrating solar power technologies use reflective
materials to concentrate the sun's heat energy, which
ultimately drives a generator to produce electricity. These
technologies include dish/engine systems and central power
towers.
Low-temperature solar collectors also absorb the sun's heat
energy, but the heat is used directly for hot water or space
heating for residential, commercial, and industrial facilities.
Wind Energy
Wind energy uses the energy in the wind for
practical purposes like generating electricity,
charging batteries, pumping water, or
grinding grain. Wind turbines convert the
kinetic energy of the wind into other forms of
energy. Large, modern wind turbines
operate together in wind farms to produce
electricity for utilities. Small turbines are
used by homeowners and remote villages to
help meet energy needs.
Geothermal Energy
Geothermal energy is the heat from the
Earth. It's clean and sustainable.
Resources of geothermal energy range
from the shallow ground to hot water
and hot rock found a few miles beneath
the Earth's surface, and down even
deeper to the extremely high
temperatures of molten rock called
magma.
Biomass Energy
The term "biomass" means any plant
derived organic matter available on a
renewable basis, including dedicated
energy crops and trees, agricultural food
and feed crops, agricultural crop wastes
and residues, wood wastes and residues,
aquatic plants, animal wastes, municipal
wastes, and other waste materials.
Biomass offers world tremendous opportunity
to use domestic and sustainable resources to
provide its fuel, power, and chemical needs
from plants and plant-derived materials.
Some departments and offices include major
programs for developing and improving
technology for biomass power; for making
bio-fuels such as ethanol and renewable
diesel; and for making plastics and chemicals
from renewable, bio-based materials.
Hydropower Energy
Although hydropower (also called hydroelectric
power) currently provides about one fifth of the
world’s electricity supply, development of the world’s
remaining technical potential could, by no means,
cover the growth in future demand. However,
carefully planned hydropower development can, and
does, make a great contribution to improving
electrical system reliability and stability throughout
the world. Also, future development will play an
important role in the improvement of living standards
in the developing world, where the greatest
hydropower potential still exists.
Ocean Energy
Ocean Thermal Energy Conversion
(OTEC) is a means of converting into
useful energy the temperature
difference between surface water of
the oceans in tropical and subtropical areas, and water at a depth
of approximately 1 000 meters which
comes from the polar regions.
Tidal Energy
Tidal power is a potential source of
energy. One disadvantage is that it is
not a continuos source of energy
since electricity can only be
generated when the tides are coming
in or going out, thus requiring energy
storage.
Questions
1. What is the meaning of “renewable
energy source”?
A renewable energy source is
considered a permanent energy
source, that can be replenished as it
is used.
2. Give examples for renewable
energy sources and non-renewable
energy sources.
Renewable energy sources:
solar,wind,tidal energy sources
Non-renewable energy sources:
coal, oil and natural gas
3. What are current and potential
energy sources?
Chemical energy, electic power,
fossil fuels, nuclear energy, solar
energy, wind energy, geothermal
energy, biomass energy, hydropower
energy, ocean energy, tidal energy
4. What are the characteristics of
energy sources?
•According to the second law of
thermodynamics, whenever energy is used,
some is always lost into the environment as a
less useful form of energy. In order for energy
sources to be useful, these must involve
processes which move towards lower energy
states and release energy at reasonable rates
(neither too fast nor too slow).
•They should be easily
accessible.
•If possible, their use should be
harmless to the environment.
•They should be cheap and
plentiful.
5. Give examples for fossil fuels.
Natural gas, oil and coal
6. What is the meaning of “fission of
a nucleus”?
Fission: Splitting a heavy nucleus
into two nuclei with smaller mass
numbers
7. What is the meaning of “nuclear
fusion”?
Fusion: Combining two light nuclei
to form a heavier, more stable
nucleus
8. What do you think about the energy
sources that are found in Turkey and
are not used very much?
Sodal energy, tidal energy, wind
energy, geothermal energy
9. What can be made by using
biomass energy?
Biomass offers world tremendous opportunity to
use domestic and sustainable resources to provide
its fuel, power, and chemical needs from plants and
plant-derived materials. Some departments and
offices include major programs for developing and
improving technology for biomass power; for
making bio-fuels such as ethanol and renewable
diesel; and for making plastics and chemicals from
renewable, bio-based materials.
10. What is the meaning of “Ocean
Thermal Energy Conversion”?
Ocean Thermal Energy Conversion
(OTEC) is a means of converting into
useful energy from the temperature
difference between surface water of the
oceans in tropical and sub-tropical
areas, and water at a depth of
approximately 1 000 meters which
comes from the polar regions.
Self Evaluation
I think that my presentation was
not bad. I was so excited.
Because of that, I could not
present it very well.
Peer Evaluation
•One of my friends said that my
presentation was lack of visual
knowledge.
• One of my friends said that I must
write the key words on the slides
and talk about them.
Sources
• www.energy.gov
• www.worldenergy.org