Life cycle thinking
All products have environmental impacts. Life cycle thinking implies the understanding that materials are extracted from the earth, converted into process materials, combined with other materials to make parts, assembled into a finished product, shipped to customers who use the products and then the products are disposed of in some fashion or recycled. Along that value chain, energy is used, waste generated, other natural resources used, etc.
Life cycle thinking seeks to develop a fuller and more complete understanding of the consumption of energy and materials, and the resulting release of emissions associated with the extraction, processing, manufacturing, use and end of life management of materials and products. Without this thought paradigm, governments, businesses and civil society are often shooting in the dark as to what strategies, actions, policy instruments, and/or incentives are needed to direct society on the journey towards environmental friendly products and services. Without an understanding of where along a product life cycle lie the greatest opportunities for environmental impact reductions (e.g., in the use phase, or the mining activity), changes may be made which will create unexpected impacts elsewhere in the product’s life cycle. That means there may be a shift of the burden to other phases in the life cycle; to other regions of the world; and to other impact cate¬gories such as from contributing to climate change by burning fossil fuels in the use phase, mostly in developed countries, to impacts on nutrient flows, increased use of pesticides, water and land use, and ultimately biodiversity loss due to intensified agriculture, often in developing countries, as described by UNEP (2009) for the case of biofuels.
Life cycle assessment (LCA) evaluates environ¬mental performance throughout the sequence of activities executed in creating a product or performing a service. Extraction and consumption of resources (including energy), as well as releases to air, water, and soil, are quantified through all stages along the life cycle of products and services. Their potential contribution to environmental impact categories is then assessed. These categories include climate change, human and eco-toxicity, ionizing radiation, and resource base deterioration (e.g., water, non-renewable primary energy resources, land). According to the ISO 14040 series, LCA is structured in four phases (Figure 1).
Figure 1: Illustration of LCA phases.
Other life cycle approaches cover carbon and water footprints only. Carbon footprint is a measure of the direct and indirect greenhouse gas (GHG) emissions associated with all activities in the product’s life cycle. Such a footprint can be calculated by performing an LCA that concentrates on GHG emissions. Water footprint is a measure of the impacts of the direct and indirect water use and consumption associated with all activities in the product’s life cycle. This measure is especially relevant for water-intensive processes and at locations where water scarcity is a serious problem.
It should be emphasized that carbon footprint and water footprint consider only one environmental aspect, while LCA considers additional aspects. Therefore, the use of LCA, and not of carbon or water footprint approaches, is recommended.
This text compilation is taken from the Shonan Guidance Principles published by UNEP-SETAC Life Cycle Initiative:
Global Guidance Principles for Life Cycle Assessment Databases
A Basis for Greener Processes and Products, page 37-38