# Conscious Mobility for Urban Spaces: Case Studies Review and Indicator Framework Design
## 4 Case Studies
### Mexico City Bus Electrification and Active Mobility Programs for Sustainable Mega-Cities  
Mexico City is one of the most populated urban centers in the world, with an estimated population of 22 million in its metropolitan area [59], representing huge mobility and transportation challenges. The increase in the vehicle fleet is estimated to be between 7 and 8 million vehicles, which has worsened the negative impact on the environment and society, representing 5% of the gross domestic product (GDP) of the city, including congestion, pollutant emission, noise, and accidents [60]. However, only 19% of the trips are made by private car, while 44% use public transport and 32% walk [44]. As can be seen, the solution to meet almost half of the mobility demand has been public transport, where motorized transport operates through 2 economic business models, the first one is highly subsidized public system, including the subway (i.e., Metro) and BRT systems, the second one based on leased concessions and made up of micro-buses (seat capacity of 7 to 30 riders) [60]. In 2005, it opened Metrobus, a BRT corridor along Avenue de Los Insurgentes [61], one of the longest street corridors in the world that crosses Mexico City, North-South. Metrobus serves roughly 12 miles of Insurgentes with 36 stations and 2 terminals. It replaced about 350 standard buses with 97 new articulated BRT vehicles. These vehicles dock at enclosed, rail-like stations, and passengers may enter or exit the vehicles at any one of four double-wide doors [45]. Fares are collected via automatic ticketing machines located at the entrance to stations; the fare is roughly USD 0.30, which enables passengers to travel any distance they choose along the corridor more cheaply [61]. Even though the BRT system was considered pretty efficient, in 2014, the Mobility law was enacted, aiming to achieve a more integrated, socially-inclusive, resistant, and people-focused mobility system, besides, in 2019, Mexico City's Strategic Mobility Plan was issue with the goal of redistributing the road space and promoting investments in sustainable methods of transport, improving infrastructures and services, and increasing accessibility and safety for all users [62]. That same year, the government announced its commitment to a 100% zero emissions corridor on Line 3 and Line 4 of the BTR system, which serves 168,000 and 65,000 passengers per day. As of 23 December 2020, a pilot project was carried out on Line 3 with the first 18-meter-long articulated bus, created specifically for Mexico City, by the EB manufacturer Yutong. Under the Metrobus Renewal Policy, it is expected that by 2030, all 81 units will be renewed. Further, in 2021, an electric bus pilot program was carried out on Line 4, implementing 12-meter-long Volvo 7900 model vehicles. These two pilot programs were monitored [59] by the International Council on Clean Transportation (ICCT) to collect operation data. Additionally, as part of the sustainable transport system, 290 electric trolleybuses are in operation [63], and the Ecobici system (bike-sharing mobility scheme) is the largest in Latin America, with 480 stations, 6000 bicycles, and 322 km of cycle paths [64]. The shift toward active mobility and electric mobility has meant a great advance in lowering pollutant concentration in the environment, where the BRT system avoids 122,000 of Co2 emissions every year [65], Ecobici avoided 4521 tons of Co2 between 2010 and 2019 [66], and a trolleybus fleet of 63 units avoided 79570 tons of Co2 every year [66].