Experimental Study On Solar Energy Underground Storing Heat Feature

The earth temperature distributionis one of major factors, which affect crop's growth. Usually, traditional heating style only increases air temperature of greenhouse. The earth temperature hardly satisfies the growth requirement of crop in the severe winter. Besides, using a lot of coal will arise the environmental pollutions seriously.The study is mainly about substituting coal with solar energy. We adopted underground storing heat style and compared it with the traditional heating way of using coal. According to physiology feature of cucumber, we designed three equips-area greenhouses for experiment, the solar energy underground storing heat system; one uses stove for heating; the third is for comparison without heating, after the study on cucumber for one growth period, we found that the average earth temperature of the first one is 5.2C higher than the third one ,the yield increased 30 percent ; the second is 0.8, 9 percent .From this we concluded that the solar heating system not only improves the output, but also reduces the utilization of fossil fuel. It also obtains economic and environment benefits at the same time.But the solar energy storing heat system has some defects that are high original investment and low thermal efficiency, so it needs further improvements.