In-stream turbines for rethinking hydropower development in the Amazon basin

Given growing energy demands and continued interest in hydropower development, it is important that we rethink hydropower to avoid detrimental socioenvironmental consequences of large dams planned in regions such as the Amazon River basin. Here, we show that ~63% of total energy planned to be generated from conventional hydropower in the Brazilian Amazon could be harnessed using in-stream turbines that use kinetic energy of water without requiring storage. At five of the nine selected planned dam sites, the entirety of energy from planned hydropower could be generated using in-stream turbines by using only a fraction of the river stretch that large dams would affect. We find the cost (US$ kWh−1) for in-stream turbines to be ~50% of the conventional hydropower cost. Our results have important implications for sustainable hydropower development in the Amazon and worldwide through transition to power generation methods that meet energy needs while minimizing the negative socioenvironment impacts. In-stream turbines could be a viable alternative to storage-based large hydropower projects. This study finds that about two-thirds of the planned hydropower generation in the Brazilian Amazon basin could be harnessed using in-stream turbines.