## 4 Results and Discussion
### Effect of Hot Water Flow Rate
The influence of the hot water flow rate in generators is exhibited in Figure 9. Since the improvement of a generator hot water flow rate lowers the collector temperature, the enhanced thermal efficiency of collectors is beneficial for the amount of solar heat. It is shown that the daily useful heat of collectors grows by 23.9% for the generator flow rate rising from 1 m\({}^{3}\)/h to 10 m\({}^{3}\)/h. However, the daily average COP of absorption chillers goes down by 12.4% simultaneously as a result of the decreased temperature of generator hot water. In general, the drop of COP in absorption subsystem is offset by the increase of solar heat, so that the daily cooling capacity of absorption subsystem goes up by 38.6% as the generator flow rate enhances from 1 m\({}^{3}\)/h to 10 m\({}^{3}\)/h. It is noteworthy that such enhancement tends to be insignificant when the flow rate of generator hot water is higher than 6 m\({}^{3}\)/h. By comparing Figure 8 with Figure 9, it can be seen that the performance of the collector as well as the absorption subsystem is more sensitive to the generator flow rate. Therefore, the suitable setting of generator flow rate is important for the efficient operation of SASCHCS. Figure 7: Hot water temperature for different \(\dot{V_{g}}\). The daily energy saving of SASCHCS for different collector flow rates based on the data of from April to October is shown in Figure 10. As expected, the energy saving of the hybrid system is approximately coincident to the cooling output of the absorption subsystem with respect to the fact that it is mainly controlled by the latter. Furthermore, it is derived that the daily energy saving  
Figure 8: Impact of collector flow rate. Figure 9: Impact of generator flow rate. increased by 20-30% for the collector flow rate grows from 1 m\({}^{3}\)/h to 10 m\({}^{3}\)/h. For example, the daily energy saving improvement based on the April, May, June, July, August, September and October data is 23.9%, 27.7%, 18.8%, 28.2%, 21%, 20.4% and 20.3%, respectively. The daily energy saving of SASCHCS for different generator hot water flow rates based on the data from April to October is demonstrated in Figure 11. It is observed that the energy saving gradually goes up with the growth of the generator hot water flow rate and tends to be flat finally. The daily saving of compressor work increases by 448%, 83.8%, 90.2%, 67.4%, 37.5%, 43.4% and 34.8%, respectively, based on the data of April, May, June, July, August, September and October when the flow rate of generator hot water grows from 1 m\({}^{3}\)/h to 10 m\({}^{3}\)/h. In the case of April to June, because the relatively high temperature of hot water (\(>\)70 \({}^{\circ}\)C at least) is required for the operation of absorption subsystems at a low flow rate of generator hot water, the extremely short duration of absorption chillers caused by the weak solar irradiance leads to the excessively poor energy saving in 1 m\({}^{3}\)/h of a generator hot water flow rate. Consequently, the appropriate flow rate of generator hot water is highly important when the SASCHCS works with low solar irradiance. Figure 7.0 Daily energy saving for different collector flow rates based on the data from Apr to Oct.