Carbon Footprint
Primary Source: Jeswani, H. and Azapagic, A. (2006) Carbon Footprint Modelling in Report on the SWOT analysis of concepts, methods, and models potentially supporting LCA. Eds. Schepelmann, Ritthoff & Santman (Wuppertal Institute for Climate and Energy) & Jeswani and Azapagic (University of Manchester), pp 166-169
Level of analysis: Micro (on substances, products, companies, person, household), meso (sectors) and Macro (on countries and regions)
Assessed aspects of sustainability: Environmental
Main purpose of the assessment:
To estimate greenhouse gases of activities, events, products, services, etc.
Detailed Description
The concept of carbon footprint is being widely used in the public debate on responsibility and mitigation against the threat of climate change.
Carbon footprint represents net emissions of CO2 and other greenhouse gases over the full life cycle of a product, process, service or organisation (Carbon Trust, 2007a). Normally, it is expressed as a CO2 equivalent (usually in kilograms or tonnes per functional unit) and as such is equivalent to the usual LCA impact category Global Warming Potential (GWP). The life cycle concept of the carbon footprint means all direct (on-site, internal) and indirect emissions (off-site, external, embodied, upstream and downstream) need to be taken into account.
Carbon footprint can be calculated using the Life Cycle Assessment (LCA) methodology (ISO 14044). The LCA approach ensures that the emissions from the whole supply chain are accounted for (Carbon Trust, 2006). PAS 2050 is a new British standard for calculating carbon footprints of goods and services, being developed by British Standards Institution (BSI). It is partly based on ISO 14044 and as such does not represent a completely new methodology (BSI, 2008).
The task of calculating carbon footprints with LCA can be approached methodologically from two different directions: bottom-up, based on Process Analysis (PA) or top-down, [...]