Greenhouse gas emissions from Brazil's Amazonian hydroelectric dams
Tropical dams are often falsely portrayed as 'clean' emissions-free energy sources. The letter by de Faria et al (2015 Environ. Res. Lett. 10 124019) adds to evidence questioning this myth. Calculations are made for 18 dams that are planned or under construction in Brazilian Amazonia and show that emissions from storage hydroelectric dams would exceed those from electricity generation based on fossil fuels. Fossil fuels need not be the alternative, because Brazil has vast potential for wind and solar power as well as opportunities for energy conservation. Because dam-building is rapidly shifting to humid tropical areas, where emissions are higher than in other climatic zones, the impact of these emissions needs to be given proper weight in energy-policy decisions.