Life cycle assessments
In a nutshell
A life cycle assessment (LCA) assesses the impact of a product on the environment, from extracting raw materials and manufacturing the product, all the way to its use and disposal.
Stages of an LCA
Life cycle assessments (LCAs) can be used to assess the overall sustainability of a product. Sustainable means using resources in a way which minimises harm to the environment and leaves enough resources for future generations. Four key stages of a product's life cycle are assessed in an LCA:
PROCEDURE
| 1.
| Extraction of raw materials
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| 2. | Manufacture
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| 3. | Usage
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| 4. | Disposal
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LCA of copper water pipes
PROCEDURE
| 1. | Extraction of copper is relatively unsustainable because high-grade copper ores are running out.
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| 2. | Converting the mined copper into pipes requires a lot of energy from fossil fuels.
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| 3. | Usage involves transportation, which requires energy.
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| 4 | Copper can be recycled, which is more sustainable than dumping the metal in a landfill.
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Recycling copper
PROCEDURE
| 1.
| The copper is collected and separated from other metals.
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| 2. | In the processing step, the copper is squashed by machines to form a flat layer of metal.
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| 3. | Solid copper is heated to form molten copper.
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| 4. | Molten copper is purified to remove contaminants.
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| 5. | The pure molten copper is cooled down to form a solid.
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| 6. | The copper is transported to factories.
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LCA of plastic bags
PROCEDURE
| 1. | Plastic bags are made of polymers. Polymers are made from non-renewable crude oil.
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| 2. | Cracking and polymerisation uses energy from crude oil.
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| 3. | Plastic bags are durable (do not get damaged easily) and can therefore be used for a long time.
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| 4. | Some plastics can be recycled but most are disposed of in landfills and are non-biodegradable (cannot be broken down by living organisms).
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LCA of paper bags
PROCEDURE
| 1. | Paper bags can be made from recycled paper or by extracting the raw material directly.
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| 2. | Manufacturing paper bags requires energy from fossil fuels.
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| 3. | Paper bags can only be reused a few times as they are not very durable, since they break quite easily.
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| 4. | Paper bags are easy to recycle and are disposed in a landfills, they are broken down by organisms easily (have a high biodegradability).
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Issues with LCAs
- It is difficult to quantify certain measurements, such as the impact of pollution, so assumptions have to be made, which can be inaccurate
- Different LCA studies investigate sustainability in different ways so it can be difficult to compare LCAs
- Data produced by companies can be biased
