Estimating CO2 Emissions for Bus Rapid Transit (BRT) Using Life Cycle Assessment: A Case Study in Rio de Janeiro City

Abstract

The amount of greenhouse gases has been growing dramatically in recent decades, producing global warming and causing climate change that affects the entire planet. To mitigate these emissions, several nations have committed to implementing measures to reduce emissions of these gases, with carbon dioxide being the main one. The transport sector is one of the leading carbon emitters. It needs to be the object of attention from government authorities and private companies so that sustainable solutions are planned and implemented to reduce the fossil fuel consumption. The emerging solutions point to implementing public transport in systems that use large-capacity vehicles, replacing conventional cars and buses. However, such systems require constructing a complex infrastructure, which will also produce emissions. Thus, it is necessary to balance the emissions produced by the new system with the emissions avoided by replacing the old system, for a clear quantification of the carbon reduction. This balance is best accomplished using the system lifecycle assessment approach. This case study presents the life cycle assessment, according to ISO 14040 standards, of the BRT system implemented in Rio de Janeiro, Brazil based on real data collected during the construction of the system. The results show that the system will take 16 years to compensate for the emissions produced, and in the life cycle, the projected reduction is about half a million tons of CO2. The study indicates a path that can be useful to planners seeking to reduce carbon in the public transport sector.