Railway idle land offers a large and underused space for solar power, yet its economic value has not been evaluated. Revenue depends on the volatile System Marginal Price (SMP) and Renewable Energy Certificate (REC) markets, whose uncertainty cannot be fully captured by static discounted cash flow (DCF) analysis. This study asks whether solar development on Korea’s railway idle land is worthwhile over the long term, and at what scale it should proceed. It applies an integrated DCF and real options analysis (ROA) framework to a proposed 438 MW project on the Honam Line in southern Korea. Price volatility is estimated from monthly SMP and REC data with a geometric Brownian motion model, and the options to expand and to contract are valued on a binomial lattice. The DCF yields a marginal net present value of USD 3.2 million. The expansion option adds USD 172.5 million and is exercised in 67% of states, raising the total project value to USD 175.7 million. Rising panel efficiency and falling capital costs move the project firmly into feasibility. Therefore, scale flexibility turns a marginal project into a strongly positive one, supporting the large-scale deployment of solar on railway idle land.

Whether hydrogen should be delivered by pipeline or by truck is a large and largely irreversible investment decision. The cost information needed for this decision varies by a factor of several across the literature, and conventional single-value comparisons can reverse their conclusions depending on which value is selected. This study introduces a risk classification framework from construction management to define cost uncertainty as probability distributions grounded in the literature and in Korean empirical records. Four delivery modes were compared, specifically new pipelines, repurposed pipelines, high-pressure tube trailers, and liquefied hydrogen tanker trucks. Their twenty-year total costs were computed by Monte Carlo simulation with 20,000 draws for each combination of transport distance (10–500 km) and annual demand (1000–1,000,000 t/yr). The results are summarized as robustness maps that display only the mode with the lowest cost in at least 80% of the 20,000 cost scenarios. The synthesized cost distributions are consistent with the Korean cost records available for comparison, one of which was reserved from the model inputs. Where a repurposable pipeline exists, repurposing is effectively the only robust choice. In new corridors, new pipelines become robustly justified from 19,191 t/yr at the reference distance of 150 km, below which lies a gray band where assumptions decide the outcome. The viability of liquefied hydrogen delivery is determined not by technology but by who bears the liquefaction plant cost, and this boundary alone raises the share of the map on which liquefied hydrogen delivery is robust from 1% to 72.4%. The effective levers that advance the transition to pipelines are the operation and maintenance (O&M) rate (45.8%), the planning horizon (38.3%), and demand commitment (23.2%) rather than the carbon price (2.2%). Four announced Korean plans are located on the map in positions consistent with their project stages, which indicates that the framework can serve as a planning-stage diagnostic tool.

With the advent of the Fourth Industrial Revolution, the adoption of digital transformation technologies has accelerated across industries. Digital transformation has become a critical task for businesses, with success depending on strategic responses to rapidly changing environments, where establishing a technology development roadmap is pivotal. This study proposes a framework for a technology roadmap aimed at promoting effective digital transformation and applies it to the Korean water industry. Key technological management areas requiring digital transformation were identified, followed by an evaluation of development trends, preferences, technology levels, and potential through expert surveys. Data were quantitatively analyzed using Euclidean distance and frequency analysis. Results indicate that the most urgent areas for digital transformation in the Korean water industry are natural environment management and prediction, water supply and customer service, water intake and resource facilities, and water purification. Essential technologies to be prioritized in each area were also derived. Unlike previous studies that only compared technological priorities, this research contributes by providing a multi-layered analysis that considers preferences, levels, and potential, constructing a more robust roadmap.