## 2 Prototype of SASCHCS  
The prototype of the SASCHCS is developed to verify the model. The corresponding prototype and its schematics are exhibited in Figures 1 and 2, respectively. The prototype consists of the collector, storage tank, absorption subsystem, compression subsystem, cooling tower, fan coil, water pump, tube, and valve. The condition of the prototype is listed in Table 1. It should be noticed that the _UA_ for different heat exchangers is obtained by the regression of operational data.  
Figure 1: Picture of prototype.  
The collector, produced by Shandong Linuo-Paradigma Co. Ltd. (Shandong, China), is the compound parabolic collector (CPC). The total aperture area of the CPC array is 27 m\({}^{2}\). The operating fluid of the CPC is water. The volume of the storage tank is 0.2 m\({}^{3}\).  
The absorption subsystem, a LiBr/H\({}_{2}\)O single effect absorption chiller, is developed by the cooperation of our team and the Guangzhou Institute of Energy Research. It is driven by solar energy exclusively and the size is based on the scale of the collector. The generator, condenser, evaporator, and absorber are the horizontal falling film of the heat exchanger. Further, its solution-heat exchanger is the plate-heat exchanger. The cooling capacity of the absorption subsystem is employed as the subcooling power in the compression subsystem.  
The compression subsystem is produced by Jiangsu CSE & CAFULL Air Conditioning Co. Ltd. (Jiangsu, China) Its refrigerant is R410A. The evaporator, condenser and subcooler of the compression  
\begin{table}
\begin{tabular}{c c c} \hline \hline
**Parameter** & **Base Condition** & **Range** \\ \hline \(\left(UA\right)_{g,as}\) (kW/\({}^{\circ}\)C) & 0.7347 & - \\ \(\left(UA\right)_{a,as}\) (kW/\({}^{\circ}\)C) & 0.8224 & - \\ \(\left(UA\right)_{c,as}\) (kW/\({}^{\circ}\)C) & 1.07 & - \\ \(\left(UA\right)_{c,as}\) (kW/\({}^{\circ}\)C) & 1.2731 & - \\ \(\left(UA\right)_{c,as}\) (kW/\({}^{\circ}\)C) & 4.1615 & - \\ \(\left(UA\right)_{c,as}\) (kW/\({}^{\circ}\)C) & 3.468 & - \\ \(\left(UA\right)_{sub}\) (kW/\({}^{\circ}\)C) & 0.2264 & - \\ \(V_{suc}\) (cm/\({}^{\circ}\)r) & 88.4 & - \\ \(T_{hnv}\) (\({}^{\circ}\)C) & 70 & 60–90 \\ \(T_{cu,s,i}\) (\({}^{\circ}\)C) & 32 & 26–38 \\ \(T_{clu,c,s,i}\) (\({}^{\circ}\)C) & 12 & 9–15 \\ \(n_{com}\) (rpm) & 1800 & 0.2–1.0 (Normalized) \\ \(m_{luv}\) (kg/s) & 0.278 & 0.2–1.0 (Normalized) \\ \(m_{cu,s,as}\) (kg/s) & 0.25 & - \\ \(m_{cu,s,as}\) (kg/s) & 0.222 & - \\ \(m_{clu,s}\) (kg/s) & 0.292 & 0.2–1.0 (Normalized) \\ \(m_{cu,s}\) (kg/s) & 0.908 & 0.2–1.0 (Normalized) \\ \(m_{clu,c,s}\) (kg/s) & 0.733 & 0.2–1.0 (Normalized) \\ \hline \hline \end{tabular}
\end{table}
Table 1: Condition of system.  
Figure 2: Schematics of prototype.  
subsystem are the plate heat exchanger as well. The compressor is the direct-current (DC) frequency conversion scroll compressor. The rated cooling capacity of the compression subsystem is 34 kW and the compressor speed is 4200 rpm. However, the experimental flow rate of the chilled water is insufficient to match with the rated output. Therefore, the maximum compressor speed is controlled at 1800 rpm in the experiment to avoid an excessively low evaporator temperature and the consequent frosting of the evaporator. Additionally, the cooling capacity of the hybrid system is delivered to the room by the fan coil. A cooling tower is used to cool the absorber and tow condensers in parallel.  
The flow rates of all the external fluids in the prototype were tested by the turbine flowmeter. Additionally, the inlet/outlet temperature of the internal/external fluid was measured by the thermocouple attached in the wall of the copper tube (wrapped by the thermal insulation material). The detailed information of the test equipment is demonstrated in Table 2. In particular, the discharge temperature of the compressor was tested by the compression subsystem itself and is shown in the data display screen.