The Presa de Itaipu or Itaipu Dam is one of the largest hydroelectric power plants in the world and is a joint project between Paraguay and Brazil. The Presa de Itaipu set a record in annual energy production from environmentally friendly sources in 2015. Perhaps the most interesting thing about this energy project is that Paraguay and Brazil were in a military conflict over the demarcation on the Parana River before the hydroelectric power plant was built. With this dam, both countries gained energy and peace, and thus prosperity. A valuable lesson for the whole world, isn't it?