Model performance assessment and experimental analysis of a solar assisted cooling system Meriem Soussi a,b , Moncef Balghouthi a,⇑ , AmenAllah Guizani a , Chiheb Bouden b a Thermal Processes Laboratory (LPT), Research and Technology Center of Energy (CRTEn), B.P. 95, 2050 HammamLif, Tunisia b Laboratory of Materials, Optimization and Energy for the Durability (LR-11-ES16), National Engineering School of Tunis, University of Tunis El Manar, Tunisia article info Article history: Received 18 February 2016 Received in revised form 12 October 2016 Accepted 18 December 2016 Keywords: Solar absorption cooling Parabolic trough collectors Performance testing Experimental analysis Primary energy consumption TRNSYS simulation abstract Due to the economic development and occupancy requests, building thermal comfort reached higher levels during the last years. Energy consumption rates have become excessive and engendered an increasing reliance on fossil-fuel reserves. Hence, the conception of energy-efficient buildings as well as applying solar cooling techniques has become a promising solution. In this context, the current work dealt with the appraisal of a solar system that drives the cooling process in an office building located in the Center of Researches and Energy Technologies in Tunisia. The solar system consisting of linear para- bolic trough solar collectors’ field coupled to a 16 kW double effect Lithium Bromide absorption chiller, supplies chilled water to a set of fan coils installed in the 126 m 2 laboratory building. A dynamic model that couples the solar cooling system with the building was developed using the TRNSYS tool and several simulations were performed to assess the case study and improve its perfor- mance. The model results were compared to the data collected during the experimental campaign con- ducted in summer 2015 and showed that the collectors efficiency was at the range of 26–35%, the COP ranged between 0.65 and 1.29, the daily maximum solar COP was approximately at 35%. However, the solar system was unable to cover 32.3% of the cooling requirements, the absorption chiller was switched on only during 53.8% of its total operating time. An improved system configuration was then studied; the integration of an auxiliary heater prior to the chiller as well as the increase of the aperture area guaran- teed high driving temperatures and more suitable conditions to the absorption chiller. As a result, the chiller operating time increased to 75.8%, the cooling power increased by 75.6%, the solar COP reaches 57% and the solar fraction averaged 87%. The summer season performances predict that the improved system configuration achieves primary energy savings that reach 82.3% compared to a classic air condi- tioning system producing the same cooling power, the yearly avoided CO 2 emissions are estimated to 2947 kg. Ó 2016 Elsevier Ltd. All rights reserved. 1. Introduction During the last years, a significant rise of the number of installed solar assisted systems has been observed all around the world. The application of these systems was either domestic hot water production, space heating or infrequently space cooling. Nevertheless, solar cooling systems appear to be the most promis- ing solar technology able to replace conventional electrical driven cooling units as the incident radiation availability and the cooling requirements are always in concordance seasonally and geo-graphically. For this reason, several analytic studies of these systems have been performed either before or after prototypes installation. Actually, the analytic studies preceding system design generally focus on the feasibility of the solar cooling system, its performance prediction and optimization. After implementation, further experimental and analytical studies are also required to assess the systems functioning and improve the operating conditions in order to develop this technology. Some reviews studies of solar assisted absorption cooling sys- tems have been realized (e.g. Allouhi et al., 2015; Boopathi and Shanmugam, 2012; Cabrera et al., 2013; Gomri et al., 2010; Henning, 2007; Sarbu and Sebarchievici, 2013, 2015). They affirmed that, based on the coefficient of performance values, the absorption systems are preferred over the adsorption systems. The comparison of the water bromide and the ammonia water absorption systems showed that H 2 O/LiBr systems operating at lower pressures and recording higher COP values are more suitable http://dx.doi.org/10.1016/j.solener.2016.12.046 0038-092X/Ó 2016 Elsevier Ltd. All rights reserved. ⇑ Corresponding author. E-mail address: balghouthi_moncef@yahoo.fr (M. Balghouthi). Solar Energy 143 (2017) 43–62 Contents lists available at ScienceDirect Solar Energy journal homepage: www.elsevier.com/locate/solener