Integrated emergy and economic evaluation of 8 hydropower plants in Zagunao Basin, Southwest of China

Abstract

Hydropower has been regarded as a clean energy to replace fossil fuels facing the climate change, while detecting the tradeoffs among renewable energy production, greenhouse gas (GHG) mitigation and ecological impacts still remains challenge. Multi-disciplinary analysis should be adopted to understand these tradeoffs. This study proposed an integrated evaluation framework based on donor-side (emergy analysis) and user-side (economic analysis) which highlighted the impacts on ecosystem services. 8 hydropower plants in Zagunao Basin, Southwest China, were adopted as the study case. The results show that impacts on water supply and biodiversity dominated ecosystem service losses. Plants with higher water head are more efficient in resource utilization, while the efficiency of plants with gravity dams are generally lower than that with grille weirs under the similar installed capacity. Lixian plant had the best performance based on emergy indicators attributed by the benefits to utilize the renewable source from the regulating flow ability of Shiziping plant. Results from fair prices reflect that all the studied plants are not profitable under current grid price. Finally, policy implications were raised based on the results.