Abstract: To avoid chilling injury on plants caused by low air temperature in Chinese solar greenhouses during winter night,an active heat storage and release system by using water as a medium was designed in this experiment.This system includes a heat energy collecting/release device,heat storage device and control device.During the day time,this system was used to absorb and store solar heat energy.During the nighttime,this system was used to release the heat energy into the greenhouse for increasing the air temperature.Results showed that solar heat energy collected rate of the system was 0.3kW/m2 and the heat energy storage was 6.9MJ/m2 on a sunny daytime,during the nighttime,the heat energy release rate was 0.2kW/㎡,the heat energy released was 5.7MJ/m2 and the heat energy use efficiency was 0.83.The average air temperatures were 6.3℃ on a sunny day and 4.6℃ on a cloudy day higher in the experiment greenhouse than those in control greenhouse. The above results indicate that the active heat storage and release system can effectively improve air temperature for safe plant production in Chinese solar greenhouse during winter night.

Key words: Chinese solar greenhouse, Heat storage, Heat release, Solar energy, New energy