This paper discusses the study on the development of potential energy in flat flow rivers using Vortex turbines and a techno-economic study. At this time, a small and medium scale hydroelectric power plant is developing by utilizing a very low head river. The type of turbine that can be applied to the very low head type is Vortex turbines. The Vortex turbine is a turbine that utilizes a whirlpool as an intermediary for energy. The results of the study revealed that the Vortex turbine is quite potential to be developed because Indonesia has many rivers with a flat flow pattern so that it fits with the Vortex turbine. Technical studies are conducted to determine the potential power generated, the types of components used, and the investment cost per kW. The technology analysis results show that the power generated by the MHPP Vortex turbine system is around 1.5 kW. The results of the economic analysis show that the total investment cost value of IDR 175,560,000 with a project NPV value is negative, and IRR is less than 10%, so the project is less commercially viable. Recommendations for project development can be funded through grant funding/government funds.