Cenários de custo e de emissões de CO2 do transporte público de Fortaleza (CE) : estudo de caso da adoção do hidrogênio verde

Abstract

This research aimed to quantify the costs of bus fares and Greenhouse Gas (GHG) emissions for the year 2030 in Fortaleza, considering two scenarios: i) one that maintains the use of the current fleet's fuel (diesel); and ii) another in which the fleet would be completely replaced by one powered by green hydrogen. To achieve this, the methodology developed by the Núcleo de Estudos das Cidades (NEC), from the Escola de Engenharia de São Carlos (EESC) at USP, was adopted for calculating the unitary value of public transportation fares. Three typologies of projection assumptions were considered. The first took into account the exclusive use of the NEC method, resulting in a value of 14,43 reais for hydrogen and 4,78 reais for diesel. The second adopted a fare adjustment based on the historical series provided by ETUFOR, resulting in a projected fare of 7,08 reais in 2030 for diesel and 16,32 reais for hydrogen. The third projection assessed a hypothetical scenario of implementing a carbon market and associated, in the passengers' final fare, a cost/subsidy for CO2 emissions for each fuel, considering the total avoided emission value until 2030. Considering the replacement of the diesel fleet with one powered by green hydrogen, the city's public transportation would avoid emitting about 151 thousand tons of CO2, resulting in values of 12,98 reais in 2030 for diesel and 10,42 reais for hydrogen. Moreover, assuming the scenario where hydrogen benefits from a carbon footprint discount and diesel is penalized, in 2029, the fare rate for hydrogen already becomes more economical than diesel: for the year 2030, the fare is 10,42 reais for hydrogen and 12,98 reais for diesel. Faced with the inferences from the proposed scenarios, the suggested horizon for 2030 is short-term but already demonstrates that hydrogen use is promising and competitive in the long run. If we consider the third typology, the use of hydrogen as fuel becomes competitive in 2029, presenting a two-reais difference for residents of Fortaleza.