الفهرس 
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Abstract
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The global electrical energy consumption is still rising and there is a steady demand to increase the
power capacity. Renewable energy is one of the major inputs for the economic, environmental and
social development of any country. Both photovoltaic (PV) and concentrating solar power (CSP)
technologies now constitute feasible commercial options for large scale power plants as well as for
smaller electricity and heat generating devices. The present work aims to manage the thermal
energy stored from CSP research plant, in order to obtain the best operating condition of CSP
system. This plant is considered standalone system. In case of grid connection, grid tied inverter is
used to connect the plant to the national grid.
The investigated plant consists of solar collector field of 120 kW peak thermal capacity, thermal
storage tank with 3 tons of therminol-66 oil, an organic rankine cycle (ORC) of 8 kW nominal
electric power production capacity, and thermally driven absorption chiller (TOC) of 35 kW cooling
capacity. The system was modeled mathematically then calculated using engineering equation
solver (EES) software program in order to analyze the performance at similar conditions to the real
ones to ensure the feasibility of the presented study. The present simulation model is verified by
using data of another study and the output results are compared. from this comparison between the
present work and the other study for the output net power versus exhaust mass flow rate work, it is
clear that, the two curves have the same trend with some acceptable deviations.
The output results were analyzed. Effect of hot oil temperature and mass flow rate on ORC output
and efficiency are investigated. Also effect of generator and evaporator temperatures on TOC
cooling capacity and coefficient of performance are obtained. Both ORC net output power and TOC
cooling capacity increase with the increase of the input thermal power. When ORC exit hot oil
. temperature is constant, the ORC output electric power and inlet thermal power increase with the
increase of the inlet hot oil temperature. When applying different working fluids, the same linearity
was found but at higher elect~ic output power.
When increasing the input thermal power for both ORC and TOC, the kWh cost decreases. The
lowest price for ORC kWh is 1.131 $/kWh when 100% of the stored thermal power is used by ORC
to generate electricity. Also, the lowest price for TOC kWh is 0.1214 $/kWh when 100% of the
stored thermal power is directed to the TOe. To compromise between both ORC and TOC, The best
operating condition is obtained when about 45.83% from stored thermal power is used for ORC and
54.17% is used for TOe. In this case, the cost of electrical kWh from ORC is about 1.26 $, while the
cost of refrigerant kWh from TOC is about 0.126 $.
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