They are private, but the Government is regulating the price and the taxes. And when you have corrupt people on both side of the isle you know what will happen.
We have this Govt company
http://www.nek.bg/cgi?d=1000
and this Govt regulator
http://www.dker.bg/indexen.php
Pretty much there is info coming out where Govt regulator accepted bribes from power companies in favors when Govt decides what the prices will be and/or gave permit to such companies for favor. And we the people are screw with the price.
It's believe the "favors" were money, apartments, house at Black sea coast etc. He made deals to by expensive green electricity from the Godmother of his child, can you believe it. I hope he go's in jail and man more to. His name is Angel Semerdzhiev
http://www.focus-fen.net/?id=n299779