Recently, due to the frequent safety accidents on the SOC(Social Overhead Capital) infrastructure, the need for appropriate maintenance measure and budgetary support for infrastructure has surfaced. Especially in the case of water facilities, while its aging rate hits as high as 20.5%, it is difficult to secure the sufficient amount of budget, hence, delaying the improvement repair of the water facilities. Therefore, this study proposes a long term solution in reducing the maintenance of the national financial burden and support the government''s policy goal of expanding the supply of renewable energy in the short term.
In this study, a solar energy construction project was assumed using the idle slope (land solar) and idle surface (water solar) of the''N Dam'' in Jeollanam-do, a maintenance and repair facility of the Korea Rural Community Corporation, analyzing the economic feasibility using the value method (NPV), and additionally evaluating the business value(ROV) reflecting the volatility of the system limit price (SMP), which is considered as a major revenue volatility factor for renewable energy projects. After analyzing the results of the net present value (NPV), in the case for land solar power(Phase1), a value of (-)123 million won was analyzed and was judged that there would be difficulties in decision making for business promotion. In addition, in the case of floating photovoltaic power generation (Phase2), the value of (+)3.52 million won(in low project cost forecast) and (-)2.66 billion won(in high project cost forecast) was analyzed and the ambiguity of decision-making was confirmed. This net present value (NPV) reanalyzed the business value by using real options analysis because uncertainty inherent in the business cannot be taken into account for this limit.
In the real option evaluation method, in the case of land solar power(Phase1) and solar power(Phase2), the defer option to improve business value is considered by taking account the passive business promotion decision-making due to the existing (-)NPV, and pending the business promotion until the business environment improves or the uncertainty is resolved and analyzed. As a result of analysis, the eNPV of land solar power(phase1) and floating solar power(phase2) was analyzed to be 322.2 million won and 2.73 billion won respectively, and this result shows that it is possible to take a different path than from the existing decision by securing an additional value compared to the existing (-)NPV. In addition, a scenario in which the facility is expanded to 5% according to changes in the future was analyzed by setting up a water solar construction project using 1% of idle water surface. As a result of analysis, the eNPV was analyzed to be 3.69 billion won, and this value means that an additional return of approximately 171.4 million won can be expected compared to the existing NPV analysis. However, it has been confirmed that this revenue has ambiguity in the promotion of expansion decision-making due to poor earnings compared to 65 billion won in extended investment costs. In this study, therefore, changes in the price of solar cell modules, which have the greatest impact on the cost of water solar power projects, were utilized, and ROV changes due to changes in the cost of business were analyzed additionally, and it was confirmed that it was reasonable to consider expansion options in the case of a decrease of 30% or more compared to the existing cost of business.