Life Cycles
Students explore various life cyclesCopyright 008 Microsoft Corporation, One Microsoft Way, Redmond, WA 98052-6399 USA. All rights reserved.
Students extend their knowledge of matter and energy cycles in organisms to engineering life cycle assessment of products. They learn about product life cycle assessment and the flow of energy through the cycle, comparing it to the flow of nutrients and energy in the life cycles of organisms.
Engineers use life cycle assessment, often called cradle-to-grave assessment, when designing and creating products. This type of analysis looks at products from raw materials through production, manufacture, packaging, distribution, use, end-of-life treatment and disposal. Life cycle assessments help engineers to understand the environmental impacts of designs at every stage of production and use, so they can implement improvements in recycling and waste reduction. One example that illustrates the use of life cycle assessment is plastic vs. paper packaging. Steps to consider in this analysis include the raw materials taken from the Earth, manufacturing of the plastic or paper material, creation of the packaging, use of the packaging, distribution of the packaged product, and disposal of the packaging, as well as air-water-noise emissions for all processes. All these issues are considered and tabulated to determine the overall environmental impact of the development of paper or plastic packaging.
After this lesson, students should be able to:
- Describe several basic steps in the life cycle assessment of products.
- Compare and contrast the life cycle of an organism and an engineered product.
- Describe the flow of energy through a product's life cycle.