warming potential contribution. A definition of carbon footprint could be “a measure of the exclusive total amount of carbon dioxide emissions that is directly and
indirectly caused by an activity or is accumulated over the life stages of a product
[32]”. The carbon footprint may include the carbon dioxide emissions only or other
greenhouse gases such as methane, nitrous oxide or fluorinated gases.
A well-structured view of the carbon footprint concept can be framed in terms of
content, significance, evolution, calculation and application [33]. The carbon
footprint can be defined as “the quantity of greenhouse gas expressed in terms of
CO 2 -equivalent, emitted into the atmosphere by an individual, organization, process, product or event from within a specified boundary [33]”. The carbon footprint
has been a relevant tool for organizations and businesses, more than as an object of
extended research within the scientific community.
The carbon footprint calculation gained maturity throughout the time and
enlarged its application. Currently, two approaches are commonly used—one based
on a life-cycle assessment, based on production and/or consumption based
accounting systems with inventory methods such as life-cycle analysis
(LCA) and/or environmental input–output analysis (EIOA), and another where a
territorial accounting system is considered, usually a city or a country, using traditional emission inventory methods with different scopes taking into account the
so-called direct only and direct and indirect emissions, respectively [34].
For the first approach, a common and transparent methodology that would state
how to incorporate both direct and indirect emissions and the different steps related
with the production of materials or equipment (life cycle and/or use only) have been
required and determinant for a proper evaluation of the emissions associated. The
definition of boundaries is one of the most critical issues on evaluating the carbon
footprint. The role of upstream and downstream emissions, the incorporation of
direct greenhouse gas emissions associated with the operation of equipment owned
by a company, and the consideration of indirect emissions from carbon dioxide
associated with electricity used need clear rules to provide a proper inventory.
Comparisons can only be performed if standardized calculations are performed over
different products and corporations.
An extended research was recently performed on the use of the carbon footprint
concept, mapping its history based on literature citation, and identifying research
hotspots, frontiers and features [35]. Besides measuring the impact on global
warming, the carbon footprint enables the identification of opportunities for mitigation measures, both from a product and a process view, evaluating improvement
efficiencies that can be translated in considerable profit benefits from materials and
energy use.
The concept of carbon footprint has been used, not only with different meanings,
but also under similar names, and applied to various contexts, rising concerns of
clarity, transparency of use and uncertainty issues. Therefore, under each application, the assumptions behind should be clearly stated.
20
J. Seixas and F. Ferreira
indirectly caused by an activity or is accumulated over the life stages of a product
[32]”. The carbon footprint may include the carbon dioxide emissions only or other
greenhouse gases such as methane, nitrous oxide or fluorinated gases.
A well-structured view of the carbon footprint concept can be framed in terms of
content, significance, evolution, calculation and application [33]. The carbon
footprint can be defined as “the quantity of greenhouse gas expressed in terms of
CO 2 -equivalent, emitted into the atmosphere by an individual, organization, process, product or event from within a specified boundary [33]”. The carbon footprint
has been a relevant tool for organizations and businesses, more than as an object of
extended research within the scientific community.
The carbon footprint calculation gained maturity throughout the time and
enlarged its application. Currently, two approaches are commonly used—one based
on a life-cycle assessment, based on production and/or consumption based
accounting systems with inventory methods such as life-cycle analysis
(LCA) and/or environmental input–output analysis (EIOA), and another where a
territorial accounting system is considered, usually a city or a country, using traditional emission inventory methods with different scopes taking into account the
so-called direct only and direct and indirect emissions, respectively [34].
For the first approach, a common and transparent methodology that would state
how to incorporate both direct and indirect emissions and the different steps related
with the production of materials or equipment (life cycle and/or use only) have been
required and determinant for a proper evaluation of the emissions associated. The
definition of boundaries is one of the most critical issues on evaluating the carbon
footprint. The role of upstream and downstream emissions, the incorporation of
direct greenhouse gas emissions associated with the operation of equipment owned
by a company, and the consideration of indirect emissions from carbon dioxide
associated with electricity used need clear rules to provide a proper inventory.
Comparisons can only be performed if standardized calculations are performed over
different products and corporations.
An extended research was recently performed on the use of the carbon footprint
concept, mapping its history based on literature citation, and identifying research
hotspots, frontiers and features [35]. Besides measuring the impact on global
warming, the carbon footprint enables the identification of opportunities for mitigation measures, both from a product and a process view, evaluating improvement
efficiencies that can be translated in considerable profit benefits from materials and
energy use.
The concept of carbon footprint has been used, not only with different meanings,
but also under similar names, and applied to various contexts, rising concerns of
clarity, transparency of use and uncertainty issues. Therefore, under each application, the assumptions behind should be clearly stated.
20
J. Seixas and F. Ferreira