Abstract
To meet Taiwan’s future load demand of five years, Taiwan Power (Taipower) Company planned the investment of transmission–lines and substations (T&S) as one of Taiwan’s important public investment projects. During the planning process, Taipower evaluated the long-term load forecast results and the generation investment plan, and planned the transmission system encompassing transmission lines and substations appropriate for each of the five years under evaluation. In the past, the investment of T&S was evaluated on basis of the total benefit of the five –year plan, emphasizing the technical benefits such as the enhanced utilization of system equipments, improved network reliability and system stability, the reduced network loss etc.. However, neither the evaluation based on individual substations and lines, nor were these substations or lines compared and prioritized for selection towards a more cost-effective investment combination. To overcome these difficulties, this research investigated the benefit- evaluation indices and their application to the T&S investment and designed methods for calculating the cost-benefit ratio for evaluating each individual lines and substations.This research evaluated the increased power supply capacity, the reduced network loss and the enhanced power supply reliability and quantify these benefits into equivalent monetary value so to evaluate the cost-benefit ratio of 161 kV T&S investment subprojects categorized with the substations as subproject core so that each 161 kV substation and its related transmission lines can be evaluated individually. This thesis develops a software to estimate the benefit of T&S investment plan and individual subprojects.