You kind of have to know who the sellers were to answer that.
But in general there was unfavorable legislation on the price they receive on electricity. Also you have Brazilian currency risk (which I see as a favorable thing only based on purchasing power parity).
The special thing about EBR is that it's majority owned by the Brazilian Govt and could be (would be) nationalized under certain extreme consequences such as a revolution or war, or even if the government just decided to do it.
That's the risk I see, but this company isn't going anywhere it's the biggest utility in SA and is trading at a quarter book value. In general I think a lot of people tend to overestimate foreign risk and I like Brazil, but it is almost ominous that EBR could be trading this low. I'm long and hoping for a return to real value.