# 03Energy resources and pathways

En03TA of the Energy topic
• ## 01 A circus of toysEn03TAnugget01 Activity

### Describing processes in terms of energy stores

What the activity is for

Here pupils can practice describing carefully chosen processes in terms of changes in energy stores. The processes must be carefully selected because pupils need to be able to easily decide what change they are to study, and to be able to identify the initial and final states of this change. If you are not careful about these then the pupils may well, with considerable justification, describe the changes in terms of different energy stores from the ones that you had in mind.

What to prepare

A set of simple, but carefully chosen toys:

• a car running down a ramp
• a music box
• a very bouncy ball
• a spring loaded toy which jumps in the air
• a simple torch

For each station of the circus, you'll need to provide a card, saying what is to be studied, how to set the system up ready for this study and the precise change to be studied (from one situation to another). In addition:

• a supply of energy store cards per pair
• two templates per pair, to put the cards on
• possibly access to the interactive objects, to use in a summarising discussion

Support sheet

What happens during this activity

A circus of processes involving toys, set up around the laboratory, so that pupils can have hands-on experience of the various devices and a direct focus for discussion.

Pupils work their way around the circus, changing to the next station after an agreed time. At each station they use the energy store cards and the templates, together with the apparatus, in order to agree on an energy description for the change they are studying.

You may instruct the pupils to record their energy descriptions using the correct words, but certainly do not expect them to redraw the cards! You will probably want to focus on a selection of processes for further plenary discussion. You might like to use one of the interactive templates on a whiteboard together with the apparatus to review the pupils' answers.

• ## 02 Modelling power stationsEn03TAnugget02 Activity

What the activity is for

This activity is to promote discussion about power stations. It can serve to introduce the modelling program VnR to a class: this software provides a simple way to express relationships between different quantities. You can then alter one quantity and see the effect on another. In this way it supports conversations you might have in the classroom, by providing a visual representation of something that might otherwise just have to be imagined.

What to prepare

• the modelling program VnR
• a data projector or interactive whiteboard
• possibly a set of computers running the modelling software

What happens during this activity

Take a simple chemical power station, and ask what the main factors are that affect the output of the station. Focus on the quantity of fuel and the warming that goes to waste, then you'll be able to build a suitable model.

Repeat the process for a wind turbine. You might then point out the common features of the structure, discussing how the different parts of the model fit together. Here you'll want to draw attention to common patterns in thinking, showing how calculating differences and multiplying factors appear in the model. It will also be important to make the distinction between the dynamic models with rate relationships and the more static models that show factors affecting the power station outputs.

You might then encourage the pupils to make up their own models, perhaps starting from the file of blank stores provided. In each case you should probably encourage elaboration on the ways in which the main store is replenished, and possibly also factors affecting waste.

Encourage pupils to share and discuss their models, perhaps whilst running them on a computer attached to the data projector, as this will allow both you and the pupil to assess their understanding of energy.

• ## 03 Investigating renewable energy sourcesEn03TAnugget03 Activity

### Powered houses

What the activity is for

This activity gives children an opportunity to plan and then carry out sensible investigations in the context of renewable energy resources. Although the investigations are based on renewable energy resources, an important part of the learning is the acquiring of skills in investigations. There are three possibilities. You could choose one, or run one-third of the class with each.

If set up in context, this activity provides plenty of opportunity for debate about the validity of evidence and the chance to relate their evidence to data from the outside world (e.g. the number of sunshine hours at various locations in the UK, or the average wind speeds at different locations).

What to prepare

Per group for vertical axis wind turbines

• one cassette motor (available from surplus stores by the hundred)
• a 50 millimetre length of 6 millimetre dowel, drilled axially for a snug fit around the spindle of the motor
• 2 or 3 toilet roll tubes
• a domestic fan
• a microjoulemeter
• a model house, having a common terminal, leading via 1, 2, 4 or 8 100 ohm resistors in parallel to 4 other terminals, so as to alter the load on the power supply

Per group for horizontal axis wind turbines

• one cassette motor (available from surplus stores by the hundred)
• a 100 millimetre length of 10 millimetre dowel, drilled radially in the centre, again for a snug fit around the spindle of the motor
• a supply of stiff card or better, corrugated card
• a domestic fan
• a microjoulemeter
• a model house, having a common terminal, leading via 1, 2, 4 or 8 100 ohm resistors in parallel to 4 other terminals, so as to alter the load on the power supply

Per group for solar cell

• a mounted solar cell (again available from surplus stores), fitted with 4 millimetre sockets
• a microjoulemeter
• a light source
• a model house, having a common terminal, leading via 1, 2, 4 or 8 100 ohm resistors in parallel to 4 other terminals, so as to alter the load on the power supply

### Carrying out the activity

What happens during this activity

Children plan an investigation to see how much energy they can extract from the source each second. There are many variables from which they can choose, many of which are important to real situations. You can alter the number, angle and area of the blades, the wind speed, the area and orientation of the solar cell, the brightness of the light source and the number of houses that the power station supplies.

Allow between one and two hours of experimental time, and do encourage preliminary testing before settling on a set of measurements to be taken carefully. Results are often worthy of a class discussion session. You might set the whole process up in terms of needing advice for a regional power station, leading to some debate about the validity and applicability of the results.

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