Energy Horizons
Workshop for Junior Cycle Science teachers
Facilitators:
Eilish McLoughlin and Damienne Letmon
Workshop facilitated and developed by
CASTeL at Dublin City University
through funding support from SEAI.
Energy Horizons Workshop
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What is Energy Horizons all about?
Energy Horizons is an exciting new programme to help young
people learn about energy through the junior cycle curriculum.
The programme explores energy and science in a real world way,
exploring how and why as a society, we need to develop new
ways of looking at our energy resources. The Sustainable Energy
Authority of Ireland aims to move Irish society towards a clean,
sustainable energy future. It‟s crucial that our young people are
educated about why we need to do this, and how.
Energy Horizons is underpinned by and supports the Junior Cycle
Science Curriculum. It will help young people to develop their
knowledge about energy, energy efficiency and conservation.
Based on sound theory, the programme involves good practice,
real life learning experiences and whole-school approaches.
Education, at all levels, plays a crucial role in helping our citizens
to understand and act on issues concerning our welfare and that
of the environment. One of the most valuable things that a
teacher can do is to work with young people on issues which will
affect their lives in the future.
Through the Energy Horizons programme, you, as a teacher, can
empower your students with knowledge about climate change and
sustainable energy, thus unleashing their potential as energy
activists in their schools, homes and society at large. This in turn
will bring about the changes that Irish society must make in order
to ensure a prosperous future.
This workshop facilitated by CASTeL has received support from SEAI (2014-2015)
Energy Horizons Workshop
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Workshop Activities
Temperature and Heat....................................................................................... 4

Investigation 1: Calibrating the Thermofilm................................................ 5

Investigation 2: Visualizing Energy Flow .................................................... 8
Solar Heating ................................................................................................. 10

Investigation 3: Solar House heating ....................................................... 11

Investigation 4: Transferring heat ........................................................... 13
Thermal Insulation .......................................................................................... 15

Investigation 5: Thermal insulation ......................................................... 16
Ice Melting ..................................................................................................... 20

Investigation 6: Observing ice melting in plates of different materials ......... 21
Energy moving ............................................................................................... 26

Investigation 8: Rolling Can ................................................................... 26
Graphically Representation of Energy ................................................................ 27

Investigation 9: Sankey Diagrams .......................................................... 29
Personal Profile ............................................................................................... 35

Investigation 10: Personal Efficiency ....................................................... 36

Investigation 11: Calculate the air miles of your shopping basket ............... 38

Investigation 12: Energy Costs‟ of Food Products ..................................... 39
Energy Challenge ............................................................................................ 42

Investigation 13: Best Cup Challenge ...................................................... 42
Activity Answers ............................................................................................. 43
This workshop facilitated by CASTeL has received support from SEAI (2014-2015)
Energy Horizons Workshop
Page 4 | 44
Temperature and Heat
Overview:
The aim here is to clarify students‟ understanding of the distinction between the
terms hot, cold, heat energy and temperature using thermofilm - a liquid crystal film
- which changes colours as it heats up.
Suggested approach:
Challenge the concepts of hot and cold as follows;
1. Let the students brain storm about ideas of hot vs. cold collecting some ideas.
2. While they are discussing set up 4 containers of water - one with hot water,
(~50 oC) , one with cold water and ice cubes (~5 oC), and the other two with
water near to blood temperature . Collect the class‟ ideas and then:
3. Ask one volunteer hold one hand in each of the first two containers. Have one
of the other students measure the temperature of each of the two buckets. Ask
the volunteer student to confirm which is hot or cold. Then get the student to
transfer both hands to the other containers and ask which hand is in the hotter
water. Have another student to check the temperature of these buckets.
4. Let students recap on their original ideas - have they changed them after the
experiment …why.
5. Let the ideas stand and continue onto the following experiments:
1. Calibrating the thermofilm
2. Visualizing Energy flow
6. After these investigations then the hot vs. cold ideas can be revisited. [our
skins have temperature senors able to detect the direction of energy flow along
the surface of our body. There send two different sensations along the nerves
of the body…..that heat energy is flowing into the skin (hot) and that heat
energy is flowing out of the skin (cold).
This workshop facilitated by CASTeL has received support from SEAI (2014-2015)
Energy Horizons Workshop

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Investigation 1: Calibrating the Thermofilm
Note: thermofilm /thermocolour film changes colour as it heats up. Before it can be
used to look at energy flow you need to relate the colour changes to temperature i.e.
calibrate it.
Equipment required:
Bunsen burner +wire gauze + heatproof mat or a hot plate + heatproof mat,
250 cm3 beaker, thermometer, test tube, thermofilm (10 cm x 5 cm)
Apparatus set-up:
What to do:
Set up the apparatus as shown. Half fill the beaker with cold water and place
on hotplate
Drop the thermofilm into the clean dry test tube. Place the thermometer into
the test tube and place both in the water.
Note the initial temperature of the water and the colour of the thermofilm.
Switch on the hot plate/light the Bunsen burner and slowly heat the water.
As the water heats up, the thermofilm changes colour. Note the temperature
reading for each of the colour changes.
When the water temperature reaches
40 oC switch off the heat.
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Energy Horizons Workshop
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Student Worksheet
Temperature Reading
Corresponding Colour
This chart is the reference for further experiments using the thermofilm.
This workshop facilitated by CASTeL has received support from SEAI (2014-2015)
Energy Horizons Workshop
Student Worksheet
Insert these labels in the correct places:
A)
This transforms chemical energy to heat energy
B)
This measures the temperature of the thermofilm
C)
This transfers heat energy to the thermofilm
This workshop facilitated by CASTeL has received support from SEAI (2014-2015)
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Energy Horizons Workshop
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Investigation 2: Visualizing Energy Flow
Equipment required:
two empty aluminium cans (tomato puree can size are fine),
an aluminium sheet (length approx. 3 times the diameter of can) with a strip of
thermofilm (5cm x 2 cm) affixed as shown in diagram.
Thermometer, ice and hot water, expanded polystyrene base (approx. 25 cm x 10 cm)
Calibration chart from previous experiment
(optional - insulating covers to fit cans, stopwatch, )
Apparatus set-up:
What to do:
Set up the apparatus as shown. Place the aluminium sheet on the expanded.
Place the aluminium cans on either side as shown.
Put a cube or two into one of the cans.
Half- filled the other can with hot water - place the thermometer in the hot
water and note the temperature.
Observe what happens referencing the calibration chart from the previous
experiment.
An extension:
Repeat the experiment note the time it takes until the thermofilm stops
changing colour
Repeat again but this time placing lids on the cans. Compare time results
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Energy Horizons Workshop
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Student worksheet
Having calibrated the thermofilm insert the appropriate label from the following:
A. High temperature
B. Low temperature
C. Heat energy flow
D. Brown
E. Green
F. Black
G. Blue
Complete each of the following by selecting the appropriate „end of sentences‟ from i)
to vi) in box below.
a) The heat energy…
b) The aluminium sheet acquires…_
c) The hot water…
d) The ice cube/s…_
e) The sheet…
f) A temperature gradient takes place
i) A temperature gradient
ii) transfers heat energy into the sheet
iii) absorbs heat energy from the sheet
iv) transfers heat energy from one
side to another
v) flows from high temperature to low
vi) when one end is hot and the other
temperature
end is cold
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Energy Horizons Workshop
Page 10 | 44
Solar Heating
Overview:
The aim is to give students some experimental evidence for greenhouse effect as well
as looking at convection currents as means of heating houses using heat from the
Sun. Again use is made of the thermofilm and the calibration chart of previous
experiment.
Suggested approach:
1. Start with a short brainstorm as to what the students know about the greenhouse
effect. Some key terms can be thrown into the mix - global warming, problem or
not? (what if surface was same temperature of moon - -20 oC) climate change,
sustainability and why the focus now, using energy from the Sun.
2. Again let the ideas stand and continue onto the following investigations:
3. Solar House heating
4. Transferring Heat
3. These experiments look at role of glass in heating and at role of convection current
in transferring heat energy as well as looking at infrared radiation.
4. Dark-coloured materials absorb infrared radiation and emit the radiation readily.
However, glass is opaque to infrared radiation. The question then arises - as it is
the infrared radiation which emitting heat energy causes a change in temperature
- how come the temperature rises in the boiling tube? The students may avert to
the fact that the strip is fixed onto black card and make the connection between
black /dark coloured material, good absorption of infrared and equally good emitter
of the radiation. The light energy from the lamp will pass thought the glass tube.
The black card t will transform this visible light into infrared (heat). This in turn
raises the temperature of the card as seen by the colour change of thermofilm. By
observing the colour trace on the film students will now need to explain the rise again as infrared is opaque to glass the air inside the tube is heated and so rises to
the top.
5. By adding layers of glass to the outside of a building can result in heat gain inside.
6. The 4th investigation illustrates how this heat energy can be transferred „round the
house‟.
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Energy Horizons Workshop
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Investigation 3: Solar House heating
Equipment needed:
Boiling tube with bung to fit + test-tube rack
2 Strip of thermofilm (10 cm x 5 cm) each on black card
Lamp + calibration chart from previous experiment
Apparatus set -up:
What to do:
Put one of the strips in the boiling tube, bung it and place it in the rack as
shown.
Place the second strip in the rack near the boiling tube.
Place the lamp about 40cm from each strip. Make sure that thermofilm side is
facing the lamp.
Switch on the lamp and observe and record any colour changes /temperature
on both strips.
Comment on your observations and findings.
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Energy Horizons Workshop
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Student Worksheet
The following paragraph relate to the activity but the sentences are in no particular
order. Rewrite them in correct order or form of flow chart if you wish.
The card emits infrared radiation.
The temperature of the card
rises. Infrared does not pass through glass. The temperature of
the air increases.
The black card transforms visible light in to
infrared (heat). This then rises to the top of the tube. Light from
the lamp passes through the glass.
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Energy Horizons Workshop

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Investigation 4: Transferring heat
Equipment needed:
2 boiling tubes + two-holed bungs to fit + boiling tube rack
Plastic tubing and glass tubing to fit into bungs
A strip of thermofilm (10 cm x 5 cm)
100 cm3 / 250 cm3 beaker
Hot /boiling water
(optional; food colouring)
Apparatus set-up:
What to do next:
Set up the apparatus as shown above. Connect the tubings as shown
Place the thermofilm in one of the boiling tubes.
Fill both tubes with cold water and bung them; ensure that there are no
airbubbles in the system.
Support the boiling tube with the film using the rack and put the other one into
the beaker.
Fill the beaker with boiling water and observe what happens to the film.
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Energy Horizons Workshop
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Student worksheet
A challenge …the diagram is of a house with glass on one outside wall but labels are
missing. Insert the appropriate labels from the list underneath the diagram.
Labels:
Cold air from the house enters the cavity
Glass allows light energy into the cavity
Air cools as it transfers heat energy to the house
Hot air moves into the house from the cavity
Wall transforms light energy to heat energy.
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Energy Horizons Workshop
Page 15 | 44
Thermal Insulation
Overview:
The aim of this exercise is to distinguish between the terms heat energy, temperature,
hot and cold. The thermofilm is used to indicate temperature changes with the students
using their own hands as energy source. If some students find their hands are too cold
to make thermofilm change suggest they use the ball of their hand instead of the thumb
or even washing their hands in tap hot water.
Care should be taken when using the following terms:

Temperature = hotness or coldness as measured by a thermometer

Heat Energy = energy flowing from high temperature to lower temperature

Hot, warm and cold = terms describing sensations caused by skin sensors.
Suggested approach:
Use the following as a starter to this activity:
Take two objects - one a conductor and the other an insulator for example a metal
spoon and a plastic spoon. Have one of the students feel both of them and
describe the sensations to the class. Ask the students, by a show of hands, how
many think that the metal spoon has a lower temperature than the plastic one.
Now tape a thermometer to each of the spoons and leave them aside for later.
There are three parts to this activity:
1.
Students experiment with the thermofilm using plastic and metal discs commenting
on findings.
2.
Students then calibrate the thermofilm
3.
Using the thermofilm students then categorise some materials into insulators
(which stop heat energy flowing - film does not change colour) and conductors
(which allow heat energy flow - film changes colour)
An extension:
Introduce student to conversion of mechanical energy to heat energy - have students
write a short sentence on a sheet of paper, then place it over the thermofilm and use an
eraser to rub out the message. Have them check the film and comment on findings.
This workshop facilitated by CASTeL has received support from SEAI (2014-2015)
Energy Horizons Workshop

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Investigation 5: Thermal insulation
a) feeling the film,
b) keeping warm - insulation
Equipment required:
a) sheet of thermofilm, small plastic disc, small metal disc,
b) sheet of thermofilm, stopwatch, thermometer, selection of materials - Al foil, paper,
cotton, polyethene.
What to do:
a) Feeling the film
i.
Place thermofilm between thumb and finger for a minute. Now look at
the film and comment on the order of the colours.
ii.
Place the film on the bench and put the plastic disc on top of it. Hold your
thumb on the disc for a minute. Comment on what you feel and observe
the thermofilm.
iii.
Repeat step ii. Using the metal disc instead of the plastic one.
iv.
Hold the both discs in your hand for a couple of minutes. Now place
them side by side on the thermofilm. Comment on the appearance of the
film underneath the film.
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Energy Horizons Workshop
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Student Worksheet
Indicate on the diagram the following areas:
black, green, brown and blue
Complete the these sentences choosing
from the following words:
•Black
•blue
•green
•cold
•warm
•thermofilm
When the thermofilm is cold is goes
colour goes to
_.
, then
When I touch metal it feels
•brown
As it warms up the
and finally to _
_.
so it gets
. The
•hot
.
The thermofilm underneath goes
_. If I touch plastic instead, it feels
underneath stays cold.
Complete the following sentences by selecting the appropriate „end of sentences‟ from i) to
iv)
a) The finger
b) The metal…
_
c) The plastic…
_
d) The thermofilm…
_
_
i) changes colour as it absorbs energy
ii) feels cold when energy flows from it
iii) transfers energy from the finger to the
film
iv) stops energy transferring from finger to
film
Underline which of the following sentences are correct:
i)
Insulators feel cold
ii)
My clothes help stop heat energy leaving my body
iii)
Conductors feel warm
iv)
My body is at the same temperature as its surrounding
v)
Insulators feel warm
vi)
Conductors feel cold
vii)
My body is at a higher temperature than its surroundings
viii)
My clothes supplies heat energy to my body
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_
Energy Horizons Workshop
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What to do:
b) keeping warm
Apparatus set- up:
i.
Using the thermometer find the temperature of both the room and your
closed hand.
ii.
Set up the apparatus as shown above. Place a sheet of Al foil on the film
and hold your thumb on the sheet for 20 seconds.
iii.
Look at thermofilm and record observations in the Table 1.
iv.
Repeat steps ii. & iii. for each of the materials.
v.
Now fill in Table 2.
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Energy Horizons Workshop
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Table 1:
Material
Observation
Table 2:
Insulators which stop heat energy
Conductors which allow heat energy
flow
flow
Extension:
Write a short message on a sheet of paper.
Place this sheet of paper on top of a sheet of thermofilm and rub out the
message using an eraser. Check the film - is there a colour change? if so why?
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Energy Horizons Workshop
Page 20 | 44
Ice Melting
Overview:
The learning aims of this activity is to enable the students to be aware that the
nature of material influences transfer of thermal energy between bodies at different
temperatures. Also to be able to classify materials according to their capability
to conduct heat and to identify variables that influence the heat conduction.
Suggested Approach:
The teacher can show the apparatus (see Fig. 6a) and stimulate students to make
predictions about the melting times
NOTE: It could be useful, at this stage, to discuss about the feeling of warmness
and coldness coming from touching different bodies, and also ask students about
their bodies‟ temperature.
At this stage, it is also interesting to discuss about the concept of thermal
equilibrium.
Figure 6a
Figure 6b
After the observation the whole class will discuss the results, by confronting them with
their own predictions and making hypotheses about the influence of different parameters
on melting times
Teachers will introduce the concept of thermal conduction by discussing with pupils how to
analyse the different parameters influencing the results (see fig. 6b).
Possible questions:
Questions referring to materials commonly used in everyday life and allowing a
discussion about thermal insulation and thermal exchanges between environments
at different temperature.
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Energy Horizons Workshop

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Investigation 6: Observing ice melting in plates of
different materials
Materials:
Squares of different dimensions (surfaces and thickness) and different materials.
A set of ice cubes of almost the same dimension and at the same temperature
(taken from the same refrigerator).
Introduction:
Whenever we touch objects made of different materials we receive feelings of warmth
or coldness. Consider the different feelings we have by walking barefoot upon a
woollen carpet or upon a marble floor. In the same way, when we touch a metal
object we have a feeling of cold quite different from the feeling that we have
by
touching a piece of wood. Can you explain why this happens?
How could you perform a classroom experiment in order to prove what you answered
to the previous question? Describe this experiment:
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Energy Horizons Workshop
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The problem:
If we want that the ice cream or deep-frozen food we have bought do not melt during
the time took to cover the distance between the store and home, we have to use
special containers assuring thermal insulation. Which material makes the container a
better insulator? Is it better to use metal, glass or plastic? By a simple experiment we
shall try to give an answer to these questions.
Materials:
6 different plates (3 of aluminium with different thickness and area, 1 of wood, 1 of
plexiglas and 1 of styrofoam)
1 surface temperature sensor
Many ice cubes approximately identical
Suggestions for the experiment:
On the desk you can see six
different plates. Each plate is
identified by a letter (from A to
F). The first three plates (A, B
and C) are made of aluminium
and differ in area and thickness.
The D is a wooden plate, the E is
plexiglas, while the last one
(F) is styrofoam.
Touch the plates and describe the thermal feelings you are receiving.
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Energy Horizons Workshop
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Now your teacher will pick up from the fridge six ice cubes approximately identical
and will put down each cube upon a different plate. Before observing what happens,
try to predict the melting order of ice cubes, starting from the quickest one. Insert
into the following table the order number (from 1 to 6) for each plate. Try to explain
your choice (if you want, you can ask your teacher to help you in measuring the plate
temperature by means of the temperature probe).
A
B
C
D
E
F
Now observe the ice cubes melting. Describe what you have observed and make a
comparison with your predictions.
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Energy Horizons Workshop
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Discussion
Why the ice cubes melt when they are put down upon the plates?
Which properties of the plates do you think may affect the melting rate of ice cubes?
Do you think that the melting rate may depend on the initial temperature of the
plates?
Which plate is, in your opinion, the best insulator and which is the best conductor?
Is the heat absorbed by each ice cube the same for all the cubes?
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Energy Horizons Workshop
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In depth analysis
The transfer of heat through solid material is known as thermal conduction. The
rate of heat transfer by conduction through a layer with area A and thickness d when
the temperature difference between external faces is T is described by the Fourier
law, which is mathematically written as:
Q
t
k

AT
d
where DQ/Dt is the rate of heat transfer and k is the thermal conductivity. This is a
typical parameter of the material of the layer. The unit is watt/m °C. Thermal insulators,
like air, show low values of conductivity (order of 10-2 W/m°C), while good conductors,
like metals, have high values of conductivity (order of 102 W/m°C).
In a given substance, thermal conductivity is a property very different from heat
capacity. Heat capacity of an object represents the required amount of heat to produce
a 1°C change in the temperature of the object. On the other hand, conductivity is the
amount of heat flowing in the unit time through a layer of the substance with unit
area and thickness when between the layer faces there is a difference of
temperature of 1°C. In other words, we could say that the heat capacity of an object
is associated to the capacity of the object to be warmed up or cooled down, while
the conductivity represents the capacity to conduct heat. A good thermal insulator, like
a Styrofoam body, has low values of conductivity and also low values of heat capacity.
For this reason, it warms up and cools down very quickly, but the heat flows across it
very slowly.
A metallic body also changes its temperature rapidly, because of low heat capacity,
but the heat flow is much more higher than in good insulators. Other materials, like
water, have an high heat capacity per unit mass and then they are used as cooling
liquids (consider for example a liquid-cooled stroke engine).
By taking into account these try to explain data related to the ice melting time for the
three aluminium plates. Do you think that these data may be interpreted only in
terms of Fourier Law? Can you consider relevant the heat capacity (i.e. the specific
heat of the substance times the mass) of the plates? Make your comments below.
Did you know?
Insulating your house is one of the ways to reduce you Building Energy Rating (BER).
For more information on BER check out: http://www.seai.ie/your_building/BER/
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Energy Horizons Workshop
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Energy moving
Overview:
The aim is to discuss predictions, observations and explanations about what happens
to energy when you roll two drink cans down a slope.

Investigation 8: Rolling Can
Equipment
Two identical cans of carbonate drinks
Ramp
What to do
Roll a pair of identical cans of carbonated drinks
down an incline.
You won‟t be surprised to find that they roll at the
same rate.
Now shake one of them so bubbles form inside, then repeat the investigation.
You‟ll be delighted to observe that:
a) the shaken can wins the race;
b) the shaken can loses the race;
c) both cans still roll together.
What‟s your explanation?
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Energy Horizons Workshop
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Graphically Representation of Energy
Overview:
The aim is to visual represent the flow of energy so as to identify energy stores,
energy transfers and points where energy could be wasted.
Energy transfer diagrams show the locations of energy stores and energy transfers.
For example, the energy transfers in the simple flashlight electric circuit (Fig. 9a) can
be represented in an energy transfer diagram (Fig. 9b).
Fig. 9a
Fig. 9b
Using an Energy Transfer Diagram we can show what happens to the energy supplied.
It is important that the energy we use is not wasted. If we use energy more efficiently
then the cost of energy will be less. The efficiency of a device that transfers energy is
the amount of the energy supplied that is transferred into energy we can usefully use.
Sankey Diagrams can be used to show all the energy transfers taking place. Arrows
are used to show the energy inputs and outputs. The thickness of the lines represents
the amount of energy flowing.
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Energy Horizons Workshop
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Suggested Approach:
Challenge the concepts of energy flow and energy efficiency by carrying out the
following exercises.
After the investigation, consider other energy transfer systems, such as cars or power
stations and discuss points where these systems could be made more efficient.
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Energy Horizons Workshop

Investigation 9: Sankey Diagrams
1. How much thermal energy does the motor produce?
•
86 Joules
•
14 Joules
•
50 Joules
•
36 Joules
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Energy Horizons Workshop
2. Which of the 3 lights is the most efficient?
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Energy Horizons Workshop
3. How much heat energy does the light bulb give out?
4.
What is the efficiency of this light bulb?
5. What is the efficiency of the CFL lamp?
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Energy Horizons Workshop
6. How much useful energy is produced by this power station?
(Hint – one small square = 200 joules)
7. What is the efficiency of this power station?
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Energy Horizons Workshop
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In-depth Analysis
The following examples show the efficiency of old filament bulbs (left) and modern
energy efficient bulbs right).
Energy Efficiency:
The efficiency of a device that transfers energy is the amount of the energy supplied
that is transferred into energy we can usefully use.
The energy efficiency of a device can be calculated using the following formula:
Useful Energy Output
%Efficiency  Total Energy Input x 100
An electric motor consumes 100 watts (a 100 joules of electrical energy per second
(J/s)) of power and gives 90 watts of usable energy power. What is it‟s efficiency ?
Useful Energy Output
%Efficiency  Total Energy Input x 100
90W
x 100
100W
 90%

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Energy Horizons Workshop
Examples of Analysing Systems for Energy Efficiency.
A) Car
A car engine transfers chemical energy, which is stored in the fuel (petrol),
into kinetic energy in the engine and wheels.
Fig 9c. Energy transfer diagram in a car engine
Fig. 9d. Sankey Diagram in a car engine
B) Power Stations
Fig. 9e Power Station (Edenderry Power Plant, Bord na Mona)
Fig. 9f Sankey energy transfer diagram for a Power Station
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Energy Horizons Workshop
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Personal Profile
Overview:
T
l
g
i g
i
it
t i
ti it i
dt i t d
t
t
l
t
t t
st d
t
t
co
b
g
t
i
i i
Suggested Approach:
Challenge the concepts of energy usage and energy saving as follows;
1. Let the students brain storm about their own personal usage of energy and
collect some ideas.
2. Distribute the self-auditing sheets. All instructions are included on the sheet.
3. Following the completion of these activity sheets, get the students to calculate
their score, they share their individual score, then discuss highest/lowest scores
and calculate the average score for the class.
4. At this point challenge the students to think of other ways they can save or
waste energy in their daily routine.
5. Continue onto the following investigations:
11. Food Miles
12. Food Labels
6. In these activities students measure how far food travels, considering both
getting the food to the consumer, as well as getting rid of waste foods away to
the landfill. Alternatively the list could be pre-populated with food items and
respective countries of origin. The Food Miles activity requires access to a
computer and is suitable as a homework assignment.
7. Altogether these activities allow the student to be more aware of their personal
energy efficiency profile and to calculate their own Carbon Number and how
their habits can have an impact on the environment, and contribute to the
concept of Carbon footprints or Carbon tax in the global sense
This workshop facilitated by CASTeL has received support from SEAI (2014-2015)
Energy Horizons Workshop

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Investigation 10: Personal Efficiency
a)Test your personal energy efficiency rating at home
Tick the box below which you think best describes your behaviour. Then add up your
scores according to the directions below and find out whether you are an energy
saver or an energy waster.
Always
Sometimes
Never
When leaving a room which is not in use I
switch off the lights
I boil the kettle with only the amount of
water I need.
I use a ring on the hob which best fits
my pot.
I don‟t leave the television, video, or
computer on standby mode when not using
them.
I only turn on the dishwasher when there‟s
a full load.
I cycle, walk or take the bus to school or to
the shops near my house.
I don‟t leave my radiator on when my
bedroom‟s not in use.
How to add up your scores:
Have you ticked a box for each statement? Okay, then give yourself 3 points for
“always”, 2 points for “sometimes” and 1 point for “never”. Add up your points and
see what they reveal about you.
What do the scores mean?
15-21 you are a super energy saver, keep up the good work!
8-14 you‟re not bad at saving energy but could do better.
0-7 You are a total energy waster and need to change your ways!
This workshop facilitated by CASTeL has received support from SEAI (2014-2015)
Energy Horizons Workshop
Page 37 | 44
b)Test your personal energy efficiency rating at school
Tick the box below which you think best describes your behaviour. Then add up your
scores according to the directions below and find out whether you are an energy
saver or an energy waster.
Always
Sometimes
Never
When leaving a room which is not in use I
switch off the lights
I use a paper towels instead of a hand-dryer.
I switch off PC screens when I am finished
using them.
I close doors when leaving a room.
I cycle, walk or take the bus to school.
When entering a room I open blinds fully.
How to add up your scores:
Have you ticked a box for each statement? Okay, then give yourself 3 points for
“always”, 2 points for “sometimes” and 1 point for “never”. Add up your points and
see what they reveal about you.
What do the scores mean?
13-18 you are a super energy saver, keep up the good work!
7-12 you‟re not bad at saving energy but could do better.
1-6 You are a total energy waster and need to change your ways!
This workshop facilitated by CASTeL has received support from SEAI (2014-2015)
Energy Horizons Workshop

Page 38 | 44
Investigation 11: Calculate the air miles of your
shopping basket
Make a list of an average weekly shopping basket of food items bought by you and
your family. Source their country of origin. Calculate their food miles using the food
miles calculator.
Estimated CO2 &
Food Item
Country of Origin
Air Miles Travelled (km)
carbon
emissions
e.g. Fair Trade
Coffee
by airplane – 1,935 kg
Brazil
8,650 km
CO2 or 528 kg Carbon
emissions
Total air miles travelled/Total CO2
emissions of your shopping basket:
The food miles calculator does not take all factors involved in the production of the goods into
account. It purely calculates the distance travelled by the item from the country of origin to
the country of destination. For instance it does not take the energy taken to produce the
product into account, the distance it had to travel from point of harvest to point of packaging,
or, when it landed in Ireland the distance it travelled to get to your local shop!
This workshop facilitated by CASTeL has received support from SEAI (2014-2015)
Energy Horizons Workshop

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Investigation 12: Energy Costs’ of Food Products
What to do:
1. Choose three different foods and put them as headings in the columns in the datasheet
provided.
2. Think about where the foods came from and different main ingredients they contain.
How many stages of transport, processing and packaging did they go through before
arriving at the shop or supermarket for you to purchase? Remember, at every stage
work was done so energy was required.
3. List as many of those stages for each food as you can think of.
4. Each stage gets awarded points depending on how much energy is involved. Award
points to the stages as follows:
a. Involved the sun‟s energy – 0 points
b. Involved farmed animals – 1 point
c. Involved human labour, machinery or processing – 1 point
d. Involved transport in Ireland– 1 point
e. Involved transport overseas – 3 points
f. Involved packaging – 2 points
Record results on the datasheet.
5. If the foods you picked have different ingredients, you will have to give points for these
too! But don‟t worry about all ingredients, just the main ones.
6. At the end, add up the points for each food. The foods with the highest points have the
highest “hidden” energy costs.
This workshop facilitated by CASTeL has received support from SEAI (2014-2015)
Energy Horizons Workshop
Page 40 | 44
Energy Costs’ of Food Product, Datasheet
Name:
Food
_
Points
Food
Date:
Points
Food
Points
Which food used most energy for its production?
Which stage of production overall required most energy – was it transport, processing,
packaging, etc.?
This workshop facilitated by CASTeL has received support from SEAI (2014-2015)
Energy Horizons Workshop
Page 41 | 44
Did you know?
Further Information for Teachers
SEAI One Good Idea have a number of factsheets and videos available with further
information on carbon numbers available at:
 Carbon Number Factsheet
http://www.seai.ie/Schools/Post_Primary/One-Good-Idea-Project/Topic_Fact_Sheets/What-s-yourcarbon-number.pdf
The Environmental Protection Agency (EPA) have a short video available about
measuring your carbon number:
 Eco Eye TV clip on measuring your carbon number
http://www.epa.ie/researchandeducation/education/educ/limitingadaptingtoclimatechange/measuringo
urcarbonfootprint/
SEAI Energy In Education promotes energy efficiency in schools and have a number
of tips for how to save energy at school. Could some of these be implemented at home
or at school? To find out ways how the whole school can get involved check out:
 Top Ten Tips for Saving Energy at School
http://vimeo.com/51626564
 Energy In Education website
http://www.energyineducation.ie/Energy_In_Education/
This workshop facilitated by CASTeL has received support from SEAI (2014-2015)
Energy Horizons Workshop
Energy Challenge

Investigation 13: Best Cup Challenge
Which is the best cup for keeping coffee hot?
Equipment needed:
Variety of Styrofoam, plastic and paper disposable cups
Hot liquid
Timer
Thermometers
Beaker/measuring cup
Questions:
Which cup material/design is the best for keeping coffee hot?
Use the flipchart to record your hypothesis, testing and conclusion
This workshop facilitated by CASTeL has received support from SEAI (2014-2015)
Page 42 | 44
Energy Horizons Workshop
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Activity Answers
Visualising energy flow:
Completing the sentences:
The heat energy flows from high temperature to low temperature
The hot water transfers heat energy into the sheet
The ice cube absorbs heat energy from the sheet
The sheet transfers heat energy from left to right
The aluminium sheet acquires a temperature gradient
A temperature gradient is when one end is hot and the other end is cold.
Thermal Insulation
Completing the sentences inserting correct words:
When the thermofilm is cold, it goes black. As it warms up, the colour goes to
brown, then green and finally to blue. When I touch metal, it feels cold. The
thermofilm underneath goes green, so it gets warm. If touch plastic instead, it
feels hot. The thermofilm underneath stays cold
Complete the sentences:
The finger feels cold when energy flows out of it
The metal transfers energy from the finger to the thermofilm
The plastic stops energy going from the finger to the thermofilm
The thermofilm changes colour as it absorbs energy
This workshop facilitated by CASTeL has received support from SEAI (2014-2015)
Energy Horizons Workshop
Underlining the correct sentences:
Insulators feel cold
My clothes help stop heat energy leaving my body
Conductors feel warm
My body is at the same temperature as its surrounding
Insulators feel warm
Conductors feel cold
My body is at a higher temperature than its surroundings
Solar House Heating
Re-writing the paragraph:
This workshop facilitated by CASTeL has received support from SEAI (2014-2015)
Page 44 | 44