Energy Resource Lesson Seven : Using a Product's Life Cycle

We consume energy directly and indirectly. The products, food, and services we purchase all have embodied energy, the energy used to create them, within them. It takes both resources and energy to make, package, and transport the products we use and grow the food we eat. It also takes energy to dispose of the products when we are done using them. Therefore, our product choices have direct and indirect economic, social, and environmental consequences. Life cycle assessment (LCA) is a tool consumers can use to make better decisions about the products they buy and how they use them. Designers and engineers use LCA to make more economical and environmentally sustainable products.

Assessing a product’s life cycle includes examining the human impacts, energy, materials, and wastes at each stage of a product’s life cycle from cradle (the inception of the idea) to the grave (disposal).

The basic areas of life cycle assessment are:

Design – Includes coming up with an idea for a product and deciding what materials will be used to make it, how it will be made, how long it will last, etc. A product’s design affects each stage of its life cycle and, therefore, its social, economic, and environmental impact.

Materials Acquisition – The process of obtaining raw materials. All products are made from some raw materials, which come directly from the Earth, like trees or iron ore. Obtaining raw materials may require harvesting timber or mining. The acquisition of raw materials uses energy, depletes natural resources, and impacts the environment. Using recycled or recovered materials usually saves energy and natural resources.

Materials Processing – The process of converting raw materials into a form that can be used to make products. Each separate process creates waste and consumes energy.

Manufacturing – The process of converting the materials into the useful product. Manufacturing processes use energy and create waste at each step.

Packaging – Many products are packaged in paper or plastic, which also undergo separate manufacturing processes that use energy, consume natural resources, and create waste. While packaging serves an important purpose, it is often excessive.

Distribution – Products are transported to different locations where they are sold, but the materials and parts used to make the product may have been transported during earlier stages in the life cycle. Transportation uses energy and generates greenhouse gases.

Use – The way products are used impacts the environment. Reusable, durable, and recyclable products conserve natural resources, use less energy, and create less waste than disposable, single-use products. Generally, the longer the useful life of the product, the less impact it has on the environment compared to other products serving the same purpose.

Reuse/Recycling – Recycling or remanufacturing products into something new reduces the amount of raw materials that have to be used in the manufacturing process and usually saves energy.

Disposal – When we throw products into the trash, we end their useful life. Disposal uses transportation energy, creates pollution, and impacts the environment by taking up landfill space.

Source: U.S. EPA, Solid Waste and Emergency Response. (2003). The Life Cycle of a CD or DVD. Poster. Washington, DC: Solid Waste and Emergency Response.

We can use pollution prevention (reduce, reuse, recycle) strategies at different stages of a product’s life cycle to help make better use of limited resources and the energy it takes to extract, transport, process, and dispose of products after their useful lives.

The hierarchy of pollution prevention is as follows:

• Reduce

The first step in pollution prevention is to reduce the use of something or substitute a less toxic material when possible. It is economically and environmentally cheaper to prevent pollution than to clean it up later. Buying products with less packaging is another way to reduce waste and unnecessary consumption of energy and resources.

• Reuse

The next step in the pollution prevention hierarchy is to reuse products. If one cannot personally reuse household items like clothes, furniture, and toys, they can be donated to second-hand stores, so that someone else can use them.

• Recycle

The last method of pollution prevention is recycling. Recycling has environmental and economic tradeoffs. It takes energy to not only produce goods, but also to recycle or dispose of them. Recycling is often a better choice than disposal, because it typically takes less energy to recycle materials than to extract, process, and transport raw materials from the Earth.