Geothermal power plant projects in Central America : technical and financial feasibility assessment model

Abstract

The geothermal resource potential makes the Central American region a prime candidate for investment in electricity power plant projects. In this study, the technical and financial feasibility of developing geothermal power plant projects in Central America is conducted. Three thermodynamic models of two groups of conventional power plants are evaluated for a range of possible values of geothermal resource temperatures (100-340°C) and mass flow rates (100-1,000 kg/s) in order to examine multiple expected scenarios. The main results are presented as contour maps of the internal rate of return (IRR) of free cash flow to equity (FCFE), net power plant output and the probability of success of accomplishing the minimum rate of return required by private investors. By using these maps, geothermal developers, who already characterize the quality of resources for geothermal projects, could identify technically and financially viable projects in terms of temperature and mass flow rate, taking into account the assumptions and limitations considered in the models. The results indicate that the geothermal power plant’s size, profitability indicators and the probability of success of geothermal power development arise from an increase in the temperature of the geothermal resource and mass flow rate. As a result, geothermal power development projects in Central America for a small power plant are not attractive to private investors, when taking into account the project’s cost of exploration and confirmation, drilling of an unknown field, and construction of the power plant and transmission line.