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Visiting Itaipu

Itaipu dam has the second largest rated capacity of all hydropower plants in the world, next after Three Gorges Dam in China. However, as the Paraná river has a more even flow throughout the year, the Itaipu dam in the end is the hydropower plant in the world that supplies the most energy.
A normal year, this plant alone supplies more than 150% of the nuclear plants in Sweden together.

The dam was built and is operated within a binational co-operation between Paraguay and Brazil, that then divide the energy in between them, The ground where it stands has a somewhat international status.

Traveling in Brazil, I off course had to see this dam with my own eyes. Let's see some pictures I took. 

I photographed this overview picture of the dam for a start. 

The dam seen from the side. It doesn't look to vast here, but it's 7235 meters long in total. The turbines outlets are underneath the water surface and cannot be seen here.

 This is the outlet of cooling water from the generators. The cooling water leaves the generator at around 80°C before it's mixed with cool drainage water and is dispersed into the Paraná river.

These are channels for draining the dam, when there is a greater flow of water than the installed equipment can handle. 

The area that is flooded by the dam. As of what Itaipu claims it has one of the smaller flooded area per generated unit of energy  in the world though.

 The white towers sticking up are hydraulic pistons for operating shutter valves to the penstocks.

Another overview.

 Photo taken standing on the top of the dam. It's huge!

 Downstreams of the powerplant.

The  white penstocks for the turbines were just massive.

Penstocks again. 

Control room for the transformer stations. The policy is to have one operator from Paraguay and one from Brazil all the time.  The operation of the dam is complicated a bit as it supplies both Paraguay and Brazil, and these countries have different main frequencies on the power grid.

The control room for the turbines. As in many other places, it's a hybrid between old analogue supervising and a newer digital system. 

 A plate giving cred to the people who built the dam.

 The shaft transferring the mechanical power from one of the turbines to a generator. The shaft and the turbine is rotating at the rather modest speed of 90 RPM on the Brazilian side with the 60 Hz system. This should mean that the generator has 80 poles, am I right?

Underneath these circular areas in the floor the generators are located.


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