Tim and Eugene decided to fly to Salta in Northern Argentina while I planned to get the bus as it was a third of the price of the flight, see a bit of the pampas and also to experience the Argentina bus service I had heard a bit about online.
This was until I was told the bus was full up and I would have to go the following day. Since I ended up with a free day I looked up what to do and saw there was a ‘Special Tour’ of the Itaipu Dam available. There was a normal tour which goes around the grounds and along the top of the dam in a bus but didn’t go inside so I thought it worthwhile to do the full deal.
To be honest I didn’t know much about the dam except that it existed and was slightly North of the Brazilian side town. I headed up on the local bus and was dropped off at a swish visitors centre where I got my visitor pass and had a look at some of the exhibits waiting for my 2pm tour.
The dam itself is something of an engineering marvel, built on the border between Paraguay and Brazil, it was the most powerful power plant in the world until the opening of the Chinese Three Gorges Dam. Because of the seasonal variation of the Yangtse river they still, however, produce about the same amount of energy in a year.
After watching a rather corporate video about the dam and the work with local community the special tour group of about 12 people were separated onto a small bus after a thorough security pat down and scan.
The first stop was in front of the dam and the spillway. Behind the dam is a large man-made lake stretching back a hundred kilometres. To control the level of the lake and pressure on the dam they allow excess water to head down what looks for all purposes like a ski jump. This only happens 5 weeks a year and this week was one of those so we were in luck.
Amazingly the amount of water careering down was more than Iguazu Falls!
The dam itself is several kilometres long and so we had about a 15 minute bus trip around and over it. After driving over the top of the Dam we then headed down to the power centre where the scale of things soon becomes apparent.
There are 20 of these tube leading down to turbines – 10 generating on the Paraguay side and 10 on the Brazilian side. Of course Paraguay couldn’t possibly need as much energy as these generate so they sell the excess back to the Brazilians so there are lines back over to the Brazil side.
The criticality of this power was shown in 2009 when there were distribution problems and consequently Sao Paulo, Rio and much more besides (include all of Paraguay) went dark
In the power centre we were able to watch the activity of the monitoring centre where a Brazilian and, of course, an equivalent Paraguayan keep a beady eye on all aspects of the dam operation.
Itaipu that day was generating almost 11 gigawatts which, to put in perspective, is almost 40% of the energy demand of the entire UK and the dam wasn’t even running at full tilt!
The interior resembles concrete cathedrals rising 200m from the foundations to the top and in poured concrete polygons for strength to hold back the reservoir.
At the end of our visit we got to go inside the turbine hall and down into the beating heart of the dam (the ground does literally shake) to see one of the generators in action. Two of these would power most of Ireland.