# Energy and Power

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28 Οκτ 2013 (πριν από 4 χρόνια και 5 μήνες)

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Foundations of Technology

Energy and Power

© 2013 International Technology and Engineering Educators Association

STEM

Center for Teaching and Learning™

Foundations of Technology

Teacher Resource

Unit 3 Lesson 1

The BIG Idea

Big Idea:

controlling of energy have been an enabling
factor in the development of technology.

© 2013 International Technology and Engineering Educators Association

STEM

Center for Teaching and Learning™

Foundations of Technology

Thermodynamics

There are four laws of thermodynamics
that help to define things like energy, the
flow of energy, and temperature.

Each law helps to define how

these physical properties

behave as well as to

determine what is and

is not possible.

© 2013 International Technology and Engineering Educators Association

STEM

Center for Teaching and Learning™

Foundations of Technology

Thermodynamics

Zeroth

Law of Thermodynamics

Helps to Define Temperature

“If each of two systems

is equal to a third, then

the first two are also

equal.”

© 2013 International Technology and Engineering Educators Association

STEM

Center for Teaching and Learning™

Foundations of Technology

Thermodynamics

The First Law of Thermodynamics:

The Law of Conservation of Energy

“Energy can neither be

created nor destroyed,

however energy can

flow from one form to

another.”

© 2013 International Technology and Engineering Educators Association

STEM

Center for Teaching and Learning™

Foundations of Technology

Thermodynamics

The First Law of Thermodynamics:

Internal Energy and the Relationship to
Temperature

“If a system has a temperature, then the
total energy of the system has three
parts

kinetic energy, potential energy,
and internal energy

and as the internal
energy increases, so does the potential
energy.”

© 2013 International Technology and Engineering Educators Association

STEM

Center for Teaching and Learning™

Foundations of Technology

Thermodynamics

The First Law of Thermodynamics:

Heat Flow is a Form of Energy Transfer

“Heat that flows from a hot system to a
cold system can be expressed as energy
transfer.”

© 2013 International Technology and Engineering Educators Association

STEM

Center for Teaching and Learning™

Foundations of Technology

Thermodynamics

The First Law of Thermodynamics:

Performing Work is a Form of Energy
Transfer

“When a tool/machine moves

an object, the object absorbs

some of the energy from the
tool/machine.”

© 2013 International Technology and Engineering Educators Association

STEM

Center for Teaching and Learning™

Foundations of Technology

Thermodynamics

The Second Law of Thermodynamics

Energy Flows Away From its Source

“Energy or heat cannot move from a cold
system to a hot system, and you cannot
continually produce work

because energy flows

away from its source.”

© 2013 International Technology and Engineering Educators Association

STEM

Center for Teaching and Learning™

Foundations of Technology

Source

Thermodynamics

The Third Law of Thermodynamics

As a System Approaches Absolute Zero,
Energy is Not Produced

“Molecules cease to move

as temperatures reach

absolute zero,

thus energy

is not produced.”

© 2013 International Technology and Engineering Educators Association

STEM

Center for Teaching and Learning™

Foundations of Technology

Thermodynamics

Quick Review:

The Zeroth Law helps to define temperature.

First Law of Thermodynamics discusses:

Law of Conservation of Energy

Internal Energy and the Relationship to
Temperature

Heat Flow is a Form of Energy Transfer

Performing Work is a Form of Energy Transfer

© 2013 International Technology and Engineering Educators Association

STEM

Center for Teaching and Learning™

Foundations of Technology

Thermodynamics

Quick Review:

The Second Law of Thermodynamics
states that energy flows away from its
source.

The Third Law of Thermodynamics states
that as a system approaches absolute
zero, energy is not produced.

© 2013 International Technology and Engineering Educators Association

STEM

Center for Teaching and Learning™

Foundations of Technology

How Energy

is Generated

© 2013 International Technology and Engineering Educators Association

STEM

Center for Teaching and Learning™

Foundations of Technology

1. Coal is transported into
the plant, where it is
burned, producing
chemical energy.

2. The heat or thermal energy created
causes water from the condenser to
form steam.

3. The steam turns
turbine, which is
attached to the
generator.

4. The generator converts the mechanical
energy into electrical energy. Electrical energy is
stored and transported to the consumer.

Power Systems

All Power Systems have a source of
energy, a process, and a load.

Using the previous example of Coal:

© 2013 International Technology and Engineering Educators Association

STEM

Center for Teaching and Learning™

Foundations of Technology

Source

Coal

Process

Combustion of Coal to Turn the Turbine

industry) Connected to the Power System

Forms of Energy

There are six major forms of energy:

1.
Thermal

or heat, the
vibration/movement of atoms within
systems.

2.

or light, the electromagnetic
energy that travels in transverse waves.

3.
Electrical

flow of an electric charge through a
conductor.

© 2013 International Technology and Engineering Educators Association

STEM

Center for Teaching and Learning™

Foundations of Technology

Forms of Energy

There are six major forms of energy:

4.
Mechanical

energy stored in the
movement of objects or systems

5.
Chemical

energy stored in the bonds of
atoms and molecules (examples:
biomass, petroleum, natural gas, and
coal)

6.
Nuclear

energy stored in the nucleus of
an atom

the energy that holds the
nucleus together

© 2013 International Technology and Engineering Educators Association

STEM

Center for Teaching and Learning™

Foundations of Technology

Renewable

Vs. Non
-
Renewable

Power plants generate electricity from
various energy resources.

Energy sources can be classified as:

© 2013 International Technology and Engineering Educators Association

STEM

Center for Teaching and Learning™

Foundations of Technology

Renewable:

Water

Wind

Solar

Non
-
Renewable:

Fossil

Fuels

Uranium

Renewable Energy

Renewable energy is energy that comes
from natural resources like water, wind,
and solar.

Hydroelectric power plants use the downward
flow of water to turn the blades of a turbine.

Wind works similarly; as wind blows, it turns

Solar power plants generate electricity by
converting the radiant energy from sunlight to
electrical energy.

© 2013 International Technology and Engineering Educators Association

STEM

Center for Teaching and Learning™

Foundations of Technology

Non
-
Renewable Energy

Nonrenewable resources are resources
that are limited or fossil fuels, like coal, oil,
and natural gas.

Fossil fuels provide around 66% of the world’s
electrical power and meet 95% of

the world’s total energy demands.

However, oil and coal power

plants produce harmful

environmental emissions.

© 2013 International Technology and Engineering Educators Association

STEM

Center for Teaching and Learning™

Foundations of Technology

Non
-
Renewable Energy

Nuclear power is also considered a
nonrenewable energy source.

Nuclear power is generated using uranium
and produces around 11% of the world’s
energy needs.

The heat generated from fission

when atoms split releases

heat energy which

produces steam and turns

© 2013 International Technology and Engineering Educators Association

STEM

Center for Teaching and Learning™

Foundations of Technology

Energy Flow Diagrams

There are two common diagrams used to
show the flow of energy within any
system:

Sankey Diagram

Flow Diagram

Both are used to show what is happening

to a particular type of energy as it is used

or changed in a process or situation.

© 2013 International Technology and Engineering Educators Association

STEM

Center for Teaching and Learning™

Foundations of Technology

Energy Flow Diagrams

A Sankey Diagram shows the type of
energy that goes into a system and how
the energy is converted, which also
includes wasted energy, usually in the
form of heat.

© 2013 International Technology and Engineering Educators Association

STEM

Center for Teaching and Learning™

Foundations of Technology

Energy
-
Flow Diagrams

A Flow Diagram depicts

how energy moves

through a system and

includes the type of

energy and how that

energy is generated and

stored.

The example to the right

shows how energy moves

through a Hybrid Car.

© 2013 International Technology and Engineering Educators Association

STEM

Center for Teaching and Learning™

Foundations of Technology