The Krka hydroelectric power plant
On August 28, 1895, the first complete alternating electrical power system in Croatia was put into operation. The system consisted of a hydroelectric power plant on the Krka River, an eleven kilometre long 3 kilovolt transmission line on wooden poles, and the consumers, the public lighting system of the city of Šibenik. The electric power plant was owned by the firm of Šupuk and Meichsner – The first authorized electrical system in Dalmatia “Krka” (Šupuk e Meichsner – Prima concessionata centrale elettrica in Dalmazia “Krka”). The architectural complex of the hydroelectric power plant consisted of two parts: the lower, underwater, to accommodate the turbines, and the upper, for the engine room and the switching station. The power plant was originally fitted with one Girard vertical turbine with transmission to the horizontal axis of the two-phase AC generator. This turbine was driven by only 3.2 m3/s of water, although a quantity of 25.81 m3/s was approved for the concession. In 1899, in order to increase the power supply capacity of the carbide factory in the immediate vicinity of the power plant, another Girard turbine was installed. (The factory burned down in a fire in the same year.) The generator voltage to Šibenik was transmitted by an 11 km long transmission line with four conductors. Apart from the public lighting of Šibenik, the hydroelectric power plant provided energy for the operation of mills, oil mills, pasta factory, and later theatres, cafes, and hotels joined the network, along with the first few households.
In 1913, the operation of the old hydroelectric power plant was suspended on the basis of a contract between the firm of Ante Šupuk and son and SUFID (Societa anonima per l’utillizzazione delle forze idrauliche della Dalmazia), and the 3.2 m3/s of water that it used was placed at the disposal of the nearby HPP Jaruga, which was owned by SUFID and was put into operation in 1904. At the beginning of the First World War, the military authorities dismantled the equipment in the old Krka power plant and the two copper conductors to Šibenik in order to use the materials for war purposes. Archaeological excavations began in 2006 to uncover the underground remains of the power plant. This was preceded by detailed investigation of the historical museum and archival material (documents, plans, photographs), and the preparation of technical documentation – geodetic and architectural. Although an abundance of material was collected, nonetheless no trace could be found of the original architectural documentation according to which the power plant was built. Invaluable aid in the preceding analysis of the architecture of the structure was offered by one very precise geodetic map of Skradinski buk waterfall from the beginning of the 20th century (1904 – 1910). The floor plan parameters of the structure and its spatial position are entered in it, with all accompanying installations (water supply channel, access roads, etc.). Through analysis of the discovered photographs showing the power plant, sufficient information was gathered to establish all the external elements necessary to begin field work. After the excavations were completed, conservation of the structure began so that the remains can be presented to the public.