Brazilian carbon footprint calculators: comparative approaches and implications of using these tools

Abstract

The increasing emergence of carbon calculators and the absence of specific standards to regulate these tools, may lead to inconsistencies in the results. This article evaluates individual carbon calculators that are publicly available in Brazil. Qualitative and quantitative analyses of 15 calculators were performed. Input and output data, conversion factors, as well as the costs associated with the possibilities of mitigation were evaluated. The analyses showed that there is a great discrepancy between the Emission Factors (EF), which have been highlighted by the coefficient of variation of EF adopted for the emission of liquefied petroleum gas (146.5%). The values of carbon stock also showed a large amplitude (139.45 to 359.84 kgCO2 tree−1). Furthermore, it was observed that tips on the possibility of reducing emissions are poorly provided by the calculators (27%). However, most tools (67%) make it possible to offset quantified emissions, and carbon offset plantations are widely suggested. The discrepancies found may affect calculators reliability, their potential for raising environmental awareness and their influence on decision-making. Thus, the diffusion of the calculators should be accompanied by more specific guidelines in order to minimize the uncertainties associated with the estimates.