## 3 Results and Analyses
### Temperature and Humidity Analysis  
Indoor temperature and humidity not only affect the growth of plants but also influence the manual work in the greenhouse. Therefore, except for the A, B, C, D, and E collection sites, two new indoor sites of F and G were set 1.8 m above the ground to measure the temperature and humidity in the photovoltaic greenhouse in winter (limited rain) and summer (thundershower to cloudy). The results of the measurements in winter and summer are shown in Figures 5 and 6, respectively. \begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline
**Date** & **Item** & **Outdoor** & **Site A** & **Site B** & **Site C** & **Site D** & **Site E** &
\begin{tabular}{c} **Compound** \\ **Average** \\ \end{tabular} \\ \hline
28 July &
\begin{tabular}{c} Light intensity \\ (kLux) \\ Light \\ transmittance \\ \end{tabular} & 34.04 & 8.30 & 12.33 & 15.13 & 10.32 & 19.39 & 12.53 \\
29 July &
\begin{tabular}{c} Light intensity \\ (kLux) \\ \end{tabular} & 51.43 & 8.47 & 12.28 & 19.10 & 11.41 & 26.16 & 14.18 \\
28 July &
\begin{tabular}{c} Light intensity \\ transmittance \\ \end{tabular} & 16.47\% & 23.87\% & 37.13\% & 22.19\% & 50.86\% & 27.57\% \\
31 July &
\begin{tabular}{c} Light intensity \\ (kLux) \\ \end{tabular} & 60.31 & 13.50 & 20.33 & 21.77 & 17.60 & 28.00 & 19.71 \\
31 July &
22.38\% &
\begin{tabular}{c} Light intensity \\ (kLux) \\ transmittance \\ \end{tabular} & 48.60 & 10.09 & 14.98 & 18.66 & 13.11 & 24.52 & 15.47 \\
23.85\% &
\begin{tabular}{c} Light \\ transmittance \\ \end{tabular} & 21.08\% & 31.27\% & 39.22\% & 27.23\% & 51.41\% & 32.35\% \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Average light intensities and transmitances in the photovoltaic greenhouse under different weather conditions in summer. Figure 5: \(Cont.\)  
Temperature and humidity extremum can reflect the temperature and humidity status directly. The maximum and minimum values of the temperature and humidity of the indoor and outdoor sites and the mean values of indoor sites in the photovoltaic greenhouse in winter and summer are shown in Tables 3 and 4, respectively. According to Figure 5 and Table 3, the outdoor environment had a larger impact on indoor temperature and humidity during morning and noon hours than in afternoon. In the afternoon, the indoor temperature and humidity tended to be stable. During 9:00-14:30, the indoor temperature was higher than the outdoor temperature, while the relative humidity was lower than the outdoor humidity; during 14:30-16:00, the indoor and outdoor temperatures had no significant difference; during 16:00-18:00, due to the illuminance and weather effects, the indoor temperature became lower than the outdoor temperature, while the relative humidity was higher than the outdoor humidity. The average values of the indoor test sites were close to those of the outdoor site. In the afternoon, due to the effect of photovoltaic modules and the weather turning from \"rainy\" to \"sunny\", the phenomenon of \"temperature inversion\" (the indoor temperature became lower than the outdoor temperature) happened. The temperature and humidity differences between the indoor test sites in the same day were not significant. The average temperature difference was 0.9 \({}^{\circ}\)C (3.6%), and the maximum difference was 2.1 \({}^{\circ}\)C (6.5%). According to Figure 6 and Table 4, during the summer thundershower to cloudy weather, the outdoor temperatures were between 26.1 and 33.5 \({}^{\circ}\)C, and the average indoor temperatures were between 26.2 and 36.2 \({}^{\circ}\)C. The indoor temperature was higher than the outdoor temperature during most of time in the day, and the maximum temperature difference was 2.7 \({}^{\circ}\)C; the outdoor relative humidity values were between 55% and 88%, and the average indoor relative humidity values were between 50.9% and 90.3%. The maximum temperature difference of the indoor collection sites was 3.9 \({}^{\circ}\)C (12.1%).