Investing in the construction of a solar power plant, especially in a country with high solar radiation like Iran, has become one of the attractive economic options. However, accurately calculating the internal rate of return (IRR) for this investment requires considering numerous realistic factors, which we will discuss in the following.
The basis for calculating the return is comparing the initial investment with the income stream generated from electricity sales over the project’s lifespan. The initial investment includes costs for purchasing or leasing land, technical studies, obtaining permits, buying equipment, and installation and commissioning.
On the other hand, the primary revenue comes from selling electricity to the grid at a guaranteed rate set by the Ministry of Energy. This rate, which is usually determined in Euros and paid in Rials, is guaranteed for a long period, for example, 20 years, thereby minimizing the risk of energy market fluctuations.

To provide a realistic calculation, factors that reduce the return must also be carefully considered. These include annual operation and maintenance (O&M) costs, typically estimated at around 1-2% of the initial investment, as well as insurance costs, taxes, and the gradual decrease in panel efficiency over time.
On the other hand, potential increases in the guaranteed purchase tariff in future contracts or the possibility of selling electricity directly to industrial consumers through private power purchase agreements (PPAs) can enhance profitability.
By incorporating all these inputs into a financial model, the **payback period** for a quality solar power plant in Iran is usually estimated to be between **5 to 8 years**. Given the useful lifespan of the panels, which exceeds **25 years**, this translates to over **15 years of net profit** for the investor. با احتساب تمامی این ورودی‌ها در یک مدل مالی، دوره بازگشت سرمایه برای یک نیروگاه خورشیدی با کیفیت در ایران معمولاً بین پنج تا هشت سال برآورد می‌شود که با توجه به عمر مفید بیش از بیست و پنج سال پنل‌ها، بیش از پانزده سال سود خالص را برای سرمایه‌گذار به ارمغان می‌آورد.

Specialized companies like **Horan Paya Energy Gostar** play a direct role in improving the return on investment (ROI) by providing detailed financial feasibility studies. They not only clarify these calculations for investors but also utilize their technical expertise and execution capabilities to optimize both initial and operational costs.
Factors such as selecting a suitable site with maximum solar irradiation, using equipment with the best price-to-efficiency ratio, and designing intelligent cleaning and monitoring systems are areas where an experienced consultant and contractor can make a significant impact to enhance the project’s ultimate profitability.
Therefore, investing in this sector is more than just an environmental initiative; it is a **long-term, low-risk economic decision with predictable returns** that can generate **sustainable income** for investors.