03-14-2017, 08:45 AM
Air conditioners make one side cold (the inside of the train), and one side hot (the outside). The hot has to go somewhere... which is the tunnels and stations. The trains would all be heating the stations, which then has to go somewhere. The metro is already very hot (some say it's because of the tires, but I don't really totally buy that), so, in short, they'll never install AC.