Abstract
Recently, the need to consider carbon neutrality in 2050 has been raised in various fields of Social Overhead Capital (SOC) public works. In the transport sector, eco-friendly railway projects that consider carbon neutrality are being promoted. Railway projects are more environmentally friendly than road projects. In general transport projects, only evaluation indicators based on benefit/cost (B/C) analysis are considered, so there are limitations in the methodology. In situations where real income per capita may increase even after accounting for inflation, such as the recent COVID-19 outbreak, calculating future monetary values at a constant value may underestimate benefits. This problem is even more pronounced for large-scale green transport projects such as railways. In this study, we propose to use the nominal Gross Domestic Product (GDP) per capita methodology to find the indicator that best represents the change in the value of travel time and apply it as a price index as a reference point for the analysis. The case analysed is the Great Train eXpress (GTX) project under construction in South Korea, and because of updating the realistic benefit value using the future time value of money methodology reflecting nominal GDP per capita, the project's B/C increased by 0.07, turning it into a project with a B/C of over 1, making it economically viable. Methodologies such as the above can contribute to the environment by increasing investment in green projects that are currently stagnant.
