With its rapidly increasing power demand of 16% p.a since 1990s along with its limited supply power capacity, how sustainable is Vietnam's electricity development? What are the major factors explaining its performance relative to other Asian countries? To answer these questions, this paper examines the Vietnamese power system from the 1990s to 2040 by using LEAP simulation. Twelve vulnerability and externality indexes regarding social-economic-environmental dimensions are calculated to assess vulnerability levels of the sector in seven scenarios. External costs of CO2, NOx, SO2 and PM10 are calculated to examine how far the costs could affect on the electricity cost in Vietnam. In sensitivity analysis, the paper assesses the impacts of inte...