Carbon impact of proposed hydroelectric dams in Chilean Patagonia

Abstract

The concern for and awareness of climate change is growing, and the world needs to react quickly and efficiently to manage the carbon intensity of the global energy industry. Making smart decisions about energy technology development requires a methodology to compare alternatives; one such methodology is a greenhouse gas emissions impact assessment. In the Aysen region of Chilean Patagonia, five hydroelectric dams with a nameplate capacity of 2,750 MW are proposed on the Rio Baker and Rio Pascua. The electricity will be transmitted 2,240 kilometers north to the industrial demand center in the Santiago vicinity. In this analysis, the greenhouse gas impact of the proposed dams is compared to the baseline scenario: developing natural gas power plants near Santiago. Emissions from four categories are calculated: construction, material embedded energy, land-use change, and operations. The main source of available data is published literature, a synthesis of which will serve as the basis for this thesis. Additional information is drawn from local contacts and discussions with local stakeholders. Of the six greenhouse gases, this study will focus on carbon dioxide and methane, reported as carbon dioxide equivalents. Results show that the natural gas alternative emits 13 times more carbon dioxide than the proposed hydroelectric plants with the high-voltage transmission line. However, the impact of deforestation to build the transmission lines is significant, and less carbon intensive options are likely available.