Evaluation of solar thermal driven cooling system in office buildings in Saudi Arabia

In this study solar driven absorption chiller is used to reduce the peak cooling load in office buildings in Saudi Arabia for different selected cities. The study is conducted for six cities of Abha, Dhahran, Hail, Jeddah, Nejran and Riyadh under three operating durations of 4, 6, and 8 hours using flat plate or evacuated tube collectors. The energy analysis concluded that flat plate collectors are better than evacuated tube collectors. However, the results from economic analysis suggest that while proposing a gas fired absorption chiller will reduce running costs, further reduction by using solar collectors is not feasible because of its high initial cost. At the best case scenario the Net Present Value of a 10 Ton Absorption chiller operated by natural gas boiler and two large flat plate collectors (12m2 each) running for 8 hours/day, 5days/week has a value of 117,000 $ and Internal Rate of Return (IRR) of 12%. Solar driven absorption chiller could be more feasible if the gas prices increases or the solar collector prices decreases significantly. Finally, government economic incentives and taxes are recommended to provide a boost for the feasibility of such projects.