This paper presents a multi-criteria evaluation analysis of the optimal price of electricity of solar power plants and small hydro power plants. The objective of this paper is to deal with the technical and economical part of the investment in the construction of solar power plant and small hydro power plant. Based on reviewed literature no paper was found that compare technical and economical analysis between solar power plant and small hydro power plant. The advantages and disadvantages of each technology in terms of technical and economical part of the placement in an area are presented. On the basis of the investment and operating costs an analysis of the viability of investment at different purchase prices of electricity is implemented, with the help of acceptance indicators. This paper presents a new approach to multi-criteria single aim valuation giving the estimation of suitability for the construction of solar power plants and small hydro power plants as a result. Single aim multi-criteria evaluation gives us the basis for deciding which technology is appropriate for placement in an area. To achieve a 10-year payback period, a multi-criteria evaluation analysis showed that the reference price (41.94 E/kWh) for solar power plants was increased by 3.3 times and for small hydro power plants by 1.4 times. (C) 2018 Elsevier Ltd. All rights reserved.