The benefits of the transportation projects are estimated by comparing the before and after project status of the vehicle operation, such as vehicle operation cost, noise cost, and air pollution cost of internal combustion engine vehicles within the project impact area. When evaluating the economic feasibility of projects such as new and expanded roads, new parking lots, and road space reconstruction, economic analysis is conducted based on the current social basic data of the projects.

Here, it is necessary to consider changes in the socioeconomic situations, which are the basic data for analysing the economic feasibility of the transportation projects. Especially, it is necessary to consider the emergence and increase of eco-friendly transportation methods such as electric vehicles, hydrogen electric vehicles, and hybrid vehicles.

Eco-friendly vehicles do not need an engine compared to internal combustion engine vehicles, so the components of the car different, and accordingly, the environmental pollution and vehicle operation costs of eco-friendly vehicles generated from road driving are different from those of internal combustion engine vehicles.  Therefore, since the current economic feasibility analysis guidelines use data such as driving costs calculated based on gasoline and diesel vehicles, it is challenging to analyse them as transportation benefits without considering expanding eco-friendly mobility.
The purpose of this study was to examine the characteristics of eco-friendly transportation and to present basic data that can be used to estimate the benefits of eco-friendly transportation in Seoul's transportation projects. Also, the data is expected to be used in feasibility analysis to estimate the benefits of transportation projects in consideration of the operation of eco-friendly vehicles in Seoul's road construction, expansion and improvement projects, road space reconstruction projects, and parking lot projects. This study examines the problems of estimating the benefits of transportation projects considering the operation of eco-friendly vehicles compared to the benefits of transportation projects estimated based on the existing internal combustion engine. It also evaluates what are the new transportation benefits considering eco-friendly transportation and how to estimate these benefits.

In this study, the methods of estimating of the transportation project benefits reflecting eco-friendly mobility were as follows. To estimate the eco-friendly benefits of the transportation projects, the studies of domestic and overseas clean vehicle operation costs related to eco-friendly mobility were investigated. The basic cost-per-km data, such as operating costs, environmental costs, and noise costs of eco-friendly vehicles(electric, hydrogen electric, and hybrid) derived from this study, were analysed and presented as transportation projects benefits based on operating costs, environmental costs, expert opinions, and literature data. In addition, benefit data was determined by analysing the Willingness-To-Pay through an expert survey to estimate eco-friendly personal mobility benefits.

Meanwhile, to better utilise the basic data of this study for the estimation of eco-friendly vehicles’ transportation benefits, research including experiments to estimate environmental costs, such as air pollution and noise costs from the operation of eco-friendly vehicles is continuously needed.