2) Station
Urban rail transit system typically sets a station each
1 � 1.5km. The station can be set on the underground, ground
and elevated. However, due to the lack of land resource at
urban in China and difficult for existing roads and housing
demolition, the vast majority of urban rail transit station
built under the underground.
Direct emissions things are mainly from carbon dioxide
out of the passengers breathing at underground station, and
the gas of indirect emissions becomes from ventilation and
escalator systems' electrical energy consumed. In particular,
the latter's amount of carbon dioxide emissions is far more
than the former. According to energy consumption statistics
of the latest large cities such as Beijing and Shanghai, the
station consumes about 55% of the total energy
consumption. It has already far exceeded the energy
consumption of vehicles. Therefore, how to reduce the
energy consumption of a subway station has become a
pressing issue.