Comparison of product carbon footprint standards with a case study on poinsettia (Euphorbia pulcherrima)

Purpose: A method to quantify the climate impact of products called product carbon footprint (PCF) has been gaining popularity in recent years. However, variations of this method have resulted in several competing standards to guide the carbon calculation process. The aim of the current paper was to compare PCF results when calculated according to the different standards. Methods: The three leading PCF standards are Publicly Available Specification (PAS) 2050:2011, ISO.DIN 2 14067 and Product Life Cycle Accounting and Reporting Standard (PARS) 2011. These standards were compared conceptually, and a case study was performed in which the PCF of a poinsettia plant produced in Germany was calculated according to all three standards. Results and discussion: The PCF results were 0.45-0.50, 0.53-0.58 and 0.53-0.59 kg carbon dioxide equivalent according to PAS 2050:2011, ISO.DIN 2 14067 and PARS 2011, respectively. According to all standards, the life cycle stage contributing the most greenhouse gases (GHGs) was the production of the poinsettia plant, and the single process with the highest emissions was the electricity use in the production. It was found that if nonrenewable fuels were used for heating instead of wood chips, then heating would be the highest GHG contributor - accounting for over 80 % of emissions of the total PCF. Conclusions: A key finding was that both the production system used and the decisions taken by the person carrying out the PCF calculation result in greater differences in the PCF result than the use of different standards. Differences among the three standards could be harmonised by more specific cut-off rules and exclusion criteria with the publication of ISO.DIN 2 14067, as well as the development and use of product category rules.