Impact Of Cool Roof On The Properties In Energy Consumption At Railway Station

In the process of using solar energy in railway station, some problems exposed. This paper tried to describe the current situation and find the reason on the basis of practical investigation and research about a representative railway station in Changsha, China.With comprehensive theoretical analyzing, a model is built by using the software EnergyPlus and adjusted with the measured data in Changsha South Railway Station. It is used to simulate the energy consumption characteristics of the railway station with the introduction of the cool roof by changing the surface reflectivity of different kinds of roof structure, the thermal conductivity of building envelope and the data of local climate. The results show that different kinds of reflectivity of cool roof have different influence on the capacity of heat transmission of roof, the required capacity of air conditioner, the energy consumption of air conditioning and lighting, and the number of comfortable hours. So it is important to make sure the energy-saving effect of cool roof that the design is appropriate. Some recommended reflectivity suited for different area and the thermal conductivity of building were given to provide a reference in the future.At the last of this paper, a comparison was drawn between the cool roof and the solar photovoltaic from the ability to reduce the energy consumption of the same railway station and to return on investment. The results show that the solar photovoltaic can reduce more energy consumption with more expensive investment than cool roof. So the cool roof can become a good choice with less money and only a little less energy-saving capacity.