Just outside of Foz do Iguaçu is Itaipu Binacional. It’s the largest hydroelectric power plant in the world in terms of generating energy. If you are interested in engineering, it’s well worth a visit.
You can get to the dam by public bus. Admission is BRA$26 for the Panoramic Tour (as of June 2014). There are tours on the hour from 8am to 4pm. Visitors board a double decker bus and are taken to viewpoints of the dam, eventually crossing over the dam into Paraguay and back to the visitor’s center. It lasts about an hour. Alternatively, a more thorough Special Tour is available for BRA$64. It takes visitors into the inner workings of the dam and runs about two and a half hours.
The first part of the tour stops at a viewing platform where there’s a large mural and huge robot statue. While on the bus and at the viewing platform, you learn many things about the dam.
I found it very interesting that the dam company created nature reserves, spawning streams for fish, rivers for recreational rafting and rowing, and is building a university for 10,000 engineering students on the grounds.
Part of the tour leaves Brazil and crosses the dam into Paraguay. 90% of the power generated by the dam supplies power to 17% of Brazil, and the other 10% supplies power to 75% of Paraguay. The dam has a capacity 40 times the water that flows over Iguaçu Falls. Itaipu Binacional crosses the Paraná River.
It’s possible to get a nice perspective of the dam from the Paraguayan side. I was especially impressed when crossing over the spillway.