Students will be able to describe how
energy is converted into power by the end
of the lesson
Students will be identify thoroughly
different forms of power by the end of the
unit
Students will be able to define Power
STL 16 Energy & Power Technologies
STL National Standards for Technological
Literacy
NES Abilities of Technological Designs
Make a list of different things that you use
everyday that requires power to operate
Refrigerators
Computers
Cell phones
Oven
Cars
Energy is the ability to do work . Nature
does not usually give us energy in a
form we can directly use. Technology
gives us the possibility to find and
release the energy we find and use it for
work .
What are different forms of energy ?
Different forms of energy include :
Mechanical energy , Thermal (Heat)
energy , Electrical energy , Chemical
energy , Nuclear energy , Radiant (
light) energy
Power is a measure of the rate of doing
work or transferring energy, usually
expressed in terms of wattage or
horsepower.
*In terms of electricity power can be
expressed as the conversion of energy
into available electricity for use.
Mechanical Power
Fluid Power
Electrical Power
Mechanical energy that is converted into
power using motion .
Example : Up and Down movement of your
legs on a bicycle pedal gives the power to
move a bicycle.
Fluid Power comes from gases and liquids
that are pressurized .
Pressurized gases provide Pneumatic
Power.
Example : Air Compressed tools used the
fluid power from air to provide the power
that allows the tools to operate
Pressurized Liquids provide Hydraulic
Power.
Example: Heavy construction equipment and
factories use hydraulic pumps to provide
more power than pneumatic power
operated tools
Electrical Power commonly uses
fossil fuel energy into electrical
power through power plants so
we can use lighting , air
conditioners, electronics , etc.
Example : Our power plants use
the energy that comes from coal ,
these power plants convert the
energy into electricity that we use
to power our homes.
Power Systems provide motion or force (propulsion) to
other technological products and systems.
Powers systems have to have a source of energy, a
process and a load.
The energy is part of the input in a power system.
The process converts the energy into a form that can
be used for work.
The load is the output.
Example : A farmer will use a pickup truck to carry
500lbs of hay for his farm animals. The load is the
force that the truck must use to carry the hay. The
energy comes from chemical energy ( Burning of the
gas ) . The process is the conversion of the chemical
energy into mechanical power that moves the truck.
How would you decide which energy type is
best for a specified purpose ?
How would you decide which energy type is best for
a specified purpose ?
Efficiency : The ability to achieve a desired result
with as little effort and waste as possible.
When communicating with someone it is more
efficient to speak to the person directly if they are
face to face rather than using a phone or mailing a
letter.
Cost : The price of energy and power
technologies.
A car is more costly to commute a mile back
and forth to school compared to the use of
a bicycle.
Environmental Impact : Some energy and power
technologies have negative environmental impacts
such as ; pollution , depletion of natural resources ,
use of green house gases , extinction of species .
Gas refineries and Nuclear power plants pollute the air ,
water and plants surrounding them . This affects the
lives of all the living creatures and may even cause
extinction .
Time Required : The time it will take to
achieve a desired goal should be
considered. When selecting power
technologies the quicker the better.
Using a nail gun rather than a hammer will
reduce the time it takes to complete a
project.
What is Power ?
Power is a measure of the rate of doing work or transferring
energy, usually expressed in terms of wattage or horsepower
Identify the different forms of power
Mechanical Power
Fluid Power
Electrical Power
Describe the importance of selecting energy and power
technologies
The importance of selecting energy and power technologies
is when we are converting energy into power it is significant
to use the most efficient, time and cost effective option.
Define Energy
Energy is the ability to do work
Students will be broken up into groups
where they will be given a form of work
such as a hammer and a power saw.
Each group is to identify the energy
source, the process, and the load.
Hammer :
Energy Source : Arms ( Mechanical Energy
)
Process: Mechanical Power , the up and
down motion of the arms holding the
hammer transfers the energy from the arm
into the hammer .
Load: Driving the nail into the wood.
Power Saw
Energy Source : Electrical energy
Process: Electrical Power , the energy we
get from the electricity that is produced
from a power plant is converted into
electrical power that allows the power saw
to work.
Load: The saw is able to cut through the
material