Seven hydro plants are already in operation on the Sava. Two more are planned downstream, close to the border with Croatia, and up to ten midstream, between Ljubljana and Trbovlje.

The three remaining downstream plants (which are already well under way) are projected to cost EUR 400m, while the price of the rest is estimated at EUR 900m to EUR 1.1bn over the next 20 years depending on the number of installations and the technology.

However, the figures are just for the energy installations; for example, the energy infrastructure for Brežice, one of the downstream power stations, is projected to account for under a half of the EUR 250m price tag.

The document suggests two national zoning plans would be adopted for the midstream section, one covering three power plants that are likely to be built and another covering the remainder of the section.

Renewables accounted for about 20% of gross final energy consumption in 2012, the last year for which data are available, short of the EU target of 25%. However, renewable electricity already accounted for nearly a third of total electricity production.