According to Reforms in electricity industry and privatization in Iran, "financial provision sources" is introduced as the most important barrier in enhancing electricity production through renewable energy. In this article by measuring and comparing Marginal Cost and electricity production through every renewable: Solar Thermal -30MW, Wind -12.5MW and Small Hydropower -1MW with fossilized technology: Steam Power Plant -400MW, Large Gas -300MW, Small Gas Power Plant -50MW and Combined cycle -400MW, suggested tariffs in buying electricity by economical study (providing financial resources – Loan from internal banks). All of the measurements are done in two scenarios: The present position in free mood and the result of directed subsidy and each of these two scenarios is studied through by considering social cost in electricity production. Finally, for supporting the sustainable energy and sustainable development in Iran and also for increasing the renewable energy quota in energy basket, the Government is proposed to encourage private investor for investment in renewable energy production in Iran. All of the measuring in this research is done through COMFAR software.