Life-cycle assessments
A life-cycle assessment or LCA is a 'cradle to grave' analysis of the impact of a manufactured product on the environment. The main stages are:
- obtaining the raw materials needed
- manufacturing the product
- using the product
- disposing of the product at the end of its useful life
The four main stages
At all stages, an LCA is likely to include information about the use of energy, transport of materials, and the release of waste substances into the environment.
1. Raw materials
All the raw materials we need come from the Earth's crust, atmosphere or oceans, or are due to living organisms. Obtaining these materials has an impact on the environment, including:
- using up limited resources such as ores and crude oil
- damaging habitats through quarrying, mining, or felling trees
2. Manufacture
The manufacture of products has an impact on the environment, including:
3. Use
The impact of a product on the environment during its use depends on the type of product. For example, a wooden chair has very little impact, unless it needs cleaning or repair. On the other hand, a car will have a significant impact.
4. Disposal
The disposal of old products has an impact on the environment, including:
- using up land for landfill sites
- whether any or all of the product can be recycled or reused
- Question
- The table shows some data about the energy needed in the life cycle of a pillow case.
Life cycle stage Energy use Raw materials 10% Manufacture 15% Use 70% Disposal 5% Discuss the use of energy during the life cycle of the pillowcase, and describe one way in which the energy use could be significantly reduced. 15% of the energy use is associated with making the pillowcase, and very little in disposing of it. The greatest use of energy happens when it is being used, probably because of washing, drying and ironing the pillowcase. Energy use could be reduced by drying it outside and without ironing it.
