The Ethiopian project proponent sponsored by foreign private companies is planning to develop a large-scale geothermal power generation project in a geothermal field in Ethiopia. The project under consideration aims to supply electricity to the national grid, achieving a GHG emissions reduction as well as contributing to the power diversification of the country, which are important pillars of the national energy policy. The objective of this study is to evaluate the technical and economic feasibility of introduction of a 20MW-scale wellhead geothermal generation unit as the first phase of the project.