In the current research, a comprehensive thermodynamic study of an innovative biomass-geothermal power
plant combined with a desalination system is presented and analyzed. The suggested system is a geothermal
based cascaded steam/organic Rankine cycle benefiting from municipal solid waste combustion in order to
enhance its performance. Besides, the exhaust gasses of municipal solid waste combustion are utilized as the
primary energy source for driving a multi-effect desalination subsystem which converts the seawater into low
salinity water. A comprehensive approach including energy and exergy analyses along with thermoeconomic
evaluation is applied to investigate the viability of the plant. First of all, validation of the presented model has
been tested by means of comparing the results with published data, through which a good agreement has achieved.
The energy and exergy efficiencies can be reached to 13.9% and 19.4% respectively while the total
product cost rate of the system is estimated to be 285.3 $/h. Moreover, environmental analysis is conducted in
terms of estimation of CO2 and NOx emissions to address the environmental benefits of utilizing municipal solid
waste combustion instead of coal for improving the performance of the geothermal power plant. Results indicate
that municipal solid waste utilization saves 8,092 tonnes of CO2 emission and 36 tonnes of NOx emission
annually in relative to coal utilization. Finally, a three-objective optimization is performed regarding exergy
efficiency, total product cost rate, and CO2 emission rate as objective functions through applying the Genetic
Algorithm in order to figure out the optimum performance of the system and the Pareto frontier is extracted. The
results of optimization indicate that in the optimum case, exergy efficiency of 20.72%, total product cost rate of
306.1 $/h and CO2 emission rate of 1967.7 tonnes/y are achievable.