Long Live the Green
The January GreenPiece debut column contained a sidebar featuring a few suggested websites for learning more about green initiatives. A recent visit to two of the sites uncovered information addressing carbon emissions and green designing—both noteworthy issues.
Carbon Emissions’ Calculated Risks
Researchers at Pittsburgh-based Carnegie Mellon University’s Green Design Institute posted an article on the Printers’ National Environmental Assistance Center (www.pneac.org), calling for more stringent measures for calculating global warming-causing carbon emissions. An edited version of the article is reprinted here with permission.
There is no universally accepted way of calculating carbon footprint. Many accepted frameworks rely on “tiers” of increasingly broad scope. Tier one generally includes emissions by a company’s own activities, such as burning gasoline in fleet vehicles or natural gas in facilities. The second tier boundary expands to include emissions from electricity and steam purchased by the company. Tier three takes into account all other emissions, including the entire supply chain of goods and services.
Most companies reporting their greenhouse gas emissions use only tier one or tier two boundaries. Carnegie Mellon researchers H. Scott Matthews, Chris T. Hendrickson and Christopher L. Weber developed a new method that estimates greenhouse gas emissions across all tiers of the supply chain for all industries.
“By far, most companies are pursuing very limited footprints—toe prints, really—instead of comprehensive ones,” said Matthews, an associate professor of civil and environmental engineering and engineering and public policy.
The team reported two-thirds of U.S. industries would overlook 75 percent of their total greenhouse gas emissions if they continue to use the same tier-one and tier-two reporting boundaries.
For instance, only 6 percent of the publishing industry’s greenhouse gas emissions result from tier-one and tier-two uses of petroleum products and electricity. However, there are large emissions from electricity and paper in the supply chain that would otherwise be ignored.