The sector of transportation accounts for 28% of all worldwide GHG emissions, the majority of them being CO2 (EPA, 2018). In densely populated areas, public transportation has proven its potential to increase the efficiency of mobility and reduce traffic and GHG emissions. However, in less populated areas, outside of main activity centers and busy corridors, fixed-route public transport has shown an inability to meet the requirements of low and scattered demand for transport. This thesis assesses microtransit as an alternative to fixed-route transit services in these areas. The present study carries out an analysis of public transport and microtransit from a purpose point-of-view, to evaluate the ways and contexts in which microtransit can become a complementary mean of transport to enhance the overall efficiency of entire mobility systems. This thesis proposes a case study in the outer metropolitan area of Barcelona to evaluate the potential traffic and GHG emissions reduction of the implementation of microtransit in a number of municipalities with a proven lack of public transportation availability and high private vehicle dependency. Here, the main characteristics of the microtransit service to become effective in the specific area of implementation are explained. A comprehensive transportation data analysis shows that traffic and CO2 emissions savings are moderate (about 10% traffic reduction and 5% CO2 emissions savings), though, the proposed service also contributes to decreasing isolation and enhancing collective transit coverage and accessibility in the area of implementation
