The East Japan Railway Company (JR-East), aiming to develop more environmentally friendly train stations, has been doing research on some sort of human-powered electricity generation system.
If the research provides reasonable results, the "ticket gate electricity generation system" could provide a fraction of the electricity consumed by huge and busy train stations.
The system relies on a series of 'piezo' elements embedded in the floor under the ticket gates, which generate electricity from the pressure and vibration they receive as people walk over it. If the system is attached to some high-efficiency storage system, these ticket gate generators could serve as a supplementary source of energy in this time of global warming awakening.
Currently the system is being tested at the JR-East head office in Shibuya and they might have installed it at other outlets by now, but it seems like it will take a while before such technologies will make it to Singapore MRT stations.