# Evaluation of Coupling PV and Air Conditioning vs. Solar Cooling Systems--Case Study from Jordan
## 2 Materials and Methods
### Solar Thermal Cooling System  
Driving absorption chillers in which the thermal energy is supplied by solar collectors and the absorption chillers provided the cooling for the purpose of supporting the compression chillers autonomously. An available option was that thermal energy could be stored to minimise the variation and extend the source of cooling after the sun has set. When functioning in the form of a heat pump, absorption chillers can also provide heat in winter.  
The installation of the solar cooling and heating system was situated on Building C's rooftop on the campus of GJU. The solar heating system comprised thirty arrays of solar collectors that were each formed from a series of five connected modules. Every module possessed eighteen tube collectors (evacuated) containing multiple parabolic collectors. The total surface area of the solar field's aperture was 450 m\({}^{2}\), while the collectors were positioned in a southerly facing direction, with an angle of 45\({}^{\circ}\) between the horizontal plane and the solar plane. The solar collector field located on the rooftop of Building C is shown in Figure 4[49].  
Figure 3: Coupled PV and air conditioning main components.  
Water was supplied at a temperature of 85 \({}^{\circ}\)C to the absorption chiller, which was equal to 44,000 kWh of thermal energy for the absorption chiller out of the 250,000 kWh generated by the collectors. The solar heating system included a total of four storage tanks (heat), where each had a capacity of 3.5 m\({}^{3}\). One of the aforementioned tanks was utilised for Building C's domestic hot water. In the solar hydraulic system, there was a hot water pump for each of the storage tanks, a pair of gas boilers (total capacity of 380 kW) and a dry cooler for the removal of surplus heat [49].  
The traditional cooling system comprised a pair of cooled multistage compression chillers, both of which were 700 kW (one operation/one standby), where one of the chillers could additionally function as a heat pump that only worked when the heating load overtook the capability of the absorbed solar availability on site, as well as the pair of  
Figure 4: (**a**) Solar thermal cooling system main components and (**b**) absorption chiller cycle.  
boilers on cold days in the winter when the amount of solar gain was negligible or zero. The multistage compression chillers' evaporator supplied chilled water during summer at a predetermined temperature [49].  
The system's internal sensors comprised pressure and temperature sensors. Measurements were taken for the pressure within the vapour space of the three containers and the bottom of the evaporator. Temperature measurements were taken at nine positions: the absorber, desorber and evaporator reservoirs; the evaporator circuit's condenser refrigerant sum; both the outlets and inlets of the solution heat exchanger. Five ultrasonic flow meters were utilised for the purpose of measuring the flow rates for the various circuits, namely, the condenser, solar collector, generator, compression chillers and evaporator. An ultrasonic heat flow meter (Ultraflow 54 DN 150-250) was employed in the primary chilled water network, whereas T550 ULTRACOLD/ULTRAHEAD (UH50) ultrasonic heat flow meter devices were used for the remaining circuits.  
The process of determining the global solar irradiance on a horizontal surface was performed using a pyranometer. Ambient air measurements were obtained using an ARFT/A-I/S sensor. Additionally, the amount of electrical energy consumed by the components required in the solar cooling system was measured (in kWh) using a watt-hour meter type iEM3150 [49].