We recently published several comments regarding the lack of established methodologies more or less official. At the moment, and waiting for the European Commission this year approves the guidelines for the environmental footprint of organizations and products (services seems not), so far there are only contemplated the UK Carbon Plan, the Mandatory Carbon Reporting the London Stock Exchange (London Stock Exchange) for listed companies, and French grenelle laws. However, in recent times, in parallel to the above are being imposed PAS 2050 from British Standards Institution (BSI), and the ISO 14064.
Other actions are also being developed to promote the implementation of methodologies and computing systems in businesses and Products as like the voluntary register and maybe a national seal from the Spanish Office for Climate Change.
The carbon footprint calculus is interesting even for companies under Kioto, because all the organization or another scopes can be taken into consideration.
The advantages of taking a carbon footprint project are very clear, and can be identified in the environmental and energy saving scopes including anticipating and responding to environmental and regulatory requirements, and aditionally in competitiveness, as like information of the CSR (Corporate Social Responasibility), partipation in CPD (Carbon Disclosure Projects), or the Dow Jones Sustainability Index (DJSI).
Multiple calculation systems are being developed for companies and products, based in systems more or less reliable, and more or less objective, but without the carbon footprint certification under a trusted and credible standard, which is important, and more important each time like BSI or ISO. Even the companies with ISO 14001 management systems, need to do it slowly, if they don't want to get obsolete. One has to realize that a footprint calculated by guides, is not verified, while a calculated according to PAS 2050 standard is, and moreover uncertainty is not optional. There is also ISO 14064 April 2012, for products, organizations and projects, but keep in mind that part 3 lets leave out suppliers, waste, etc..
It's very important to know that carbon footprints of different organizations or same products from different companies are not directly comparable, because the considered scope for calculation will be different with high probability. Comparison has to be made with oneself, oneself carbon footprint of today is compared with the one in the future years, since the objective, is to reduce it
There are already some companies working on it (Construction, Designation of Origin, Feeding, Drinks,...), you can trust ATEC+ID to start and finish your calculation of the carbon footprint !!!!!