Calculating carbon footprints, or toe-prints?
Seema Singh -
Sunday, August 17, 2008 3:25 PM
Calculating carbon footprint has become almost fashionable and with dozens of calculators available online, one can even calculate one's individual or a household's footprint. But a surfeit of calculators is creating confusion, and controversy, as there is no universally accepted way of calculating carbon footprints.
As a result, say researchers from the Carnegie Mellon University in the latest issue of Environmental Science & Technology, two-thirds of US industries would overlook 75% of their total greenhouse gas emissions if they continue to use the same method. In effect, the present system of calculation amounts to just "toe-prints", and not footprints, they say.
In this paper researchers argue accepted frameworks of tracking industry carbon emissions rely on "tiers" which are increasing in scope. Tier one generally includes emissions by the company's own activities, such as burning gasoline in fleet vehicles or natural gas in its facilities. The second tier boundary expands to include emissions from electricity and steam purchased by the company. Tier three includes all other emissions, including the entire supply chain of goods and services.
"The average industry has only 14 percent of its total greenhouse gas emissions in tier one and 12 percent in tier two for a total of 26 percent," and this is clearly limited in scope, they say.
To facilitate comprehensive calculation, encompassing all sectors of the economy, they have created a new website which offers new tools and will help companies in good decision-making.
Will this find favour with the industry?