With population growth, access to energy resources and supplying them to many countries around
the world is essential. The use of fossil fuels in order to provide energy causes greenhouse gas
emissions that pollute the environment and cause global warming. Also, by reducing freshwater
resources, fresh water supply is one of the main challenges in many countries. Therefore, using
multigeneration cycles for power and fresh water, which also utilize solar thermal energy, is
essential. This thesis examines and thermodynamically analyzes the combined power generation
cycle. The cycle includes the Brighton cycle, steam Rankine cycle, and organic Rankine cycle.
The thermodynamic analysis will include energy and exergy analysis, which includes mass balance
equations, energy balance, entropy generation rate of different parts of the cycle, exergy balance
equations, exergy destruction rate of different parts of the cycle, energy efficiency, exergy
efficiency, etc. For this purpose, an open Brayton cycle with an air-working fluid has been chosen
as the primary cycle. The hot air from the gas turbine is recovered by a heat exchanger and
transferred to the steam Rankine cycle that uses water as the working fluid. Next, the organic
Rankine cycle with R152a working fluid is added to the studied cycle. In this regard, the effect of
combined cycle arrangement in terms of series and parallel, the effect of the internal and external
combustion system of the Brayton gas cycle has been investigated. Further, to reduce the amount
of fuel consumption, which will result in the reduction of greenhouse gas emissions and
environmental pollution, solar energy is used, and the solar system of the heliostat and the solar
tower is added to the mentioned cycle. In order to use the waste heat of the cycle and provide fresh
water, the water desalination system is added to the final cycle by the humidification dehumidification method. The effect of different configurations of the multigeneration powe