studied the small geothermal power plant in America and Japan at
capacity around 100-1,000 kW. The technologies of the slim hole and
binary-cycle technology were selected to use for the off-grid area. And,
the environment affect from the geothermal power plant was lower than
the fossil power plant which was similarly Brophy [5], Kose [6] and
Dagdas [7]. For the simulation studies, the selection of suitable working
fluids for the organic rankine cycle (ORC) system was the hot issue
which had many reports to study this topic such as Hettiarachchi et al