The factory, located in Silistra, on the Danube river, will reach its projected design capacity of 18 megawatts (MW) per year by adding a second and a third production line, Alfa Finance Holding, of which Kaolin is part, said in a statement.
Solarpro CEO Nikolay Berov told SeeNews in April the factory will reach full capacity at the end of the current year.
Solarpro opened the factory with a single production line earlier this year and the first PVs were produced at the end of March. The company has invested 20 million euro ($29.07 million) in the project so far.
Solarpro (www.solarpro.bg), set up in 2007, is 80% owned by Kaolin. Berov holds the remainder.
Kaolin shares, a component of the blue-chip SOFIX index of the Bulgarian Stock Exchange (BSE), ended 2.59% lower at 5.65 levs ($4.18/2.9 euro) in a volume of 3,650 shares on Friday.
(1 euro = 1.95583 Bulgarian levs)