Page 127 - Design for Environment A Guide to Sustainable Product Development

106 Cha pte r Se v e n

Choosing Environmental Performance Metrics
Relationship of Metrics to Indicators
In the context of DFE, environmental performance metrics are quanti-
tative parameters used to measure design improvement with respect to
environmental goals. Because of their fundamental role in the develop-
ment process, metrics are essential to the successful practice of DFE.
As mentioned above, any environmental indicator (such as energy
usage) can correspond to a variety of metrics. Examples of environ-
mental metrics that can be used to establish product or process design
objectives include the following:
Energy usage metrics
• Total energy consumed during the product life cycle
• Renewable energy consumed during the life cycle
• Power used during operation (e.g., for electrical products)
Water usage metrics
• Total fresh water consumed during manufacturing
• Water consumption during product end-use (e.g., for
laundry products)

Material burden metrics
• Toxic or hazardous materials used in production
• Total industrial waste generated during production
• Hazardous waste generated during production or use
• Air emissions and water effluents generated during
production
• Greenhouse gases and ozone-depleting substances
released over life cycle
Recovery and reuse metrics
• Product disassembly and recovery time
• Percent of recyclable materials available at end-of-life
• Percent of product recovered and reused
• Purity of recyclable materials recovered
• Percent of recycled materials used as input to product
Source volume metrics
• Product mass (for specified functionality)
• Useful operating life
• Percent of product disposed of or incinerated
• Fraction of packaging or containers recycled