## Activity Introduction

Quick summary: Students will investigate the amount of waste being produced by Australians each year, as well as recycling rates and greenhouse gas emissions, by analysing graphs and statistics. They will then learn about Waste to Energy (WtE) technologies employed at Visy’s Kraft Mill in Tumut and compare energy output and efficiency with coal power plants. Students will also investigate calorific value and how WtE facilities can reduce large quantities of waste from landfill and prevent the associated carbon emissions. Students will use a variety of mathematical skills to complete this investigation including percentage, rate, formulas (efficiency), data analysis and problem solving.

This activity has been developed in partnership with Visy. For over 70 years Visy has been committed to finding sustainable solutions for Australia’s recyclables and helping to reduce local landfills. Visy collects, receives and sorts paper, cardboard, glass, plastics, steel and aluminium from households, businesses and schools with the purpose of reusing these products in the re-manufacture of new packaging products.

Learning intentions:

• Students will understand how materials that aren’t recycled can cause problems
• Students will understand how clean and sustainable technologies, including waste-to-energy facilities, can reduce environmental impacts
• Students will understand how to use a variety of mathematical skills to solve problems and how to identify trends in data.

21st century skills:

### Australian Curriculum Mapping

Content descriptions:

Year 7 Maths

• Find percentages of quantities and express one quantity as a percentage of another, with and without digital technologies (ACMNA158).
• Investigate, interpret and analyse graphs from authentic data (ACMNA180).

Year 8 Maths

• Solve problems involving the use of percentages, including percentage increases and decreases, with and without digital technologies (ACMNA187).
• Solve a range of problems involving rates and ratios, with and without digital technologies (ACMNA188).

Year 9 Maths

• Solve problems involving direct proportion. Explore the relationship between graphs and equations corresponding to simple rate problems (ACMNA208).
• Additional – Express numbers in scientific notation (ACMNA210).

General capabilities: Numeracy, Critical and creative thinking, Ethical understanding.

Cross-curriculum priority: Sustainability OI.8.

Relevant parts of Year 7 Mathematics achievement standards: Students solve problems involving percentages and all four operations with fractions and decimals. They interpret simple linear representations and model authentic information.

Relevant parts of Year 8 Mathematics achievement standards: Students solve everyday problems involving rates, ratios and percentages.

Relevant parts of Year 9 Mathematics achievement standards: Students interpret ratio and scale factors in similar figures. They apply the index laws to numbers and express numbers in scientific notation.

Topic: Recycling, Sustainability.

Unit of work: Visy Education – Secondary Mathematics.

Time required: 75 mins.

Level of teacher scaffolding: Medium – the teacher will need to provide context and scaffolding where necessary and lead the investigation.

Resources required:

Keywords: Percentage, rate, efficiency, waste-to-energy, landfill, graphs, statistics.

The information and statistics included in this document are approximate and have been simplified for educational/illustrative purposes. They should not be relied upon for any other purpose.

Cool Australia’s curriculum team continually reviews and refines our resources to be in line with changes to the Australian Curriculum.

## Teacher Preparation

Learning intentions: Students will...

• ... understand how materials that aren't recycled can cause problems
• ... understand how clean and sustainable technologies, including waste-to-energy facilities, can reduce environmental impacts.

Success criteria: Student can...

• ... recognise trends in data and understand effects
• ... use efficiency and calorific value calculations to make comparisons
• ... name one specific problem caused by the production of waste
• ... be able to use a variety of mathematical skills to solve problems
• ... be able to identify trends in data.

Teacher content information: What do you do with the things you no longer want or need, such as the packaging from the food you buy or bottles you drink from? Many of us have grown up thinking of this as 'waste', as something we need to just get rid of. But what if we think of these materials as a resource for creating new and useful products? What if we can re-imagine how we think abo

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## Thought starter: Is there a way to turn waste into energy?

#### Part A: How much waste is there?

1. Have a look at the graph below. This is showing how much waste Australia has generated each year since 1996, and how much waste we are projected to make by 2036.

(Source: Energy from Waste in Australia - is there a future? - MRA Consulting, 2016)

Use this graph to calculate the projected percentage increase in waste generation from 1996 to 2036.

Table 1. Projected percentage increase in waste generation from 1996 to 2036

 Working: The amount of waste is projected to increase by approximately  %

Find the approximate amount of waste for 2018 and compare this to the 1996 value. Why do you think we are producing so much more waste now, than in 1996? Can you think of any reasons?

2. Now have a look at the following graphs and quote. Can you describe any trends in this data? Can you make any observations?

(Source: Energy from Waste in Australia - is there a fu

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