Solar energy is one of the most important types of renewable energy in Iran. Solar systems are more acceptable in Iran due to their availability. In this article, the economic indicators of a Kw400 power plant in Iran are discussed. Regarding the investments of this sector, we have examined all the costs of the construction of the power plant and using the main analysis and profit analysis techniques, we evaluate and make economic calculations. Computer results have been evaluated as 25% and 30% discount and 40% inflation. The capital return rate of this power plant is 25.09% and the payback period of this power plant is 9 years. NPV with a 25% discount in the ninth year is 845.35 million Rials and with a 30% discount rate, it is 26809.88 million Rials. Also, the internal rate of return is calculated as IRR = 25.08%.