Abstract: Photovoltaic greenhouses are developed rapidly in Ningxia, in this paper second-generation solar greenhouse was chosen as the control (CK), photovoltaic solar greenhouse (D1), photovoltaic film double dual greenhouse (D2) and combining light with shade solar greenhouse (D3, solar greenhouse D3a, shade of greenhouse D3b) were chosen as treatments, the weather in every month in winter and the typical internal environment difference were analyzed in these photovoltaic greenhouse in Ningxia, and the costs and benefits of photovoltaic building were also analyzed to clarify the overwinter characteristics of each photovoltaic greenhouse environment. The results showed that the maximum temperature and light intensity of D1 were significantly higher than that of CK and other photovoltaic greenhouse in winter, the minimum temperature of CK was the highest and average humidity of CK was the lowest, the average temperature of D3a was lower than CK, but the humidity and light intensity were significantly higher than CK, temperature and light intensity of D2 and D3b were significantly lower than other greenhouses, but humidity were significantly higher than other greenhouses. In typical sunny, cloudy, snowy days, the temperature and light intensity of D2 were the lowest, and the humidity was the highest. The temperature in snowy day of D1 was lower than CK, but other typical weather temperature was the highest and humidity was the lowest. There was no significant difference in D3a and CK. The power generation of each photovoltaic greenhouse in each month was D1>D3>D2, and the construction cost of photovoltaic greenhouses could be recovered after 10.15 years. According to the comprehensive analysis, the inner greenhouse environment of D1 was better than CK, D3a was close to CK. D1, D3a and CK were suitable for fruit and vegetable production in winter. The winter temperature of D2 was below 0 ℃, which was not suitable for mushroom cultivation. D3b greenhouse environment was still suitable for mushroom cultivation.

Key words: photovoltaic greenhouse, environmental comparison, typical weather, photovoltaic input, electricity generation income