Combined project of EUR 1 billion to support renewables

Secure and stable complementarity and use of different sources of energy are the concept behind project Vis Viva in Croatia’s southern province of Dalmatia. Its segments are the construction of a combined cycle cogeneration natural gas plant at lake Peruća, a pumped storage hydropower plant at nearby Vrdovo, with a new reservoir, connecting gas pipeline Dugopolje-Peruća and power transmission line Peruća-Konjsko with a substation at Hrvace, together with both existing and planned solar and wind power facilities.

Together they allow for the storage of surplus electricity and its use when needed the most or when it is most cost effective, and a backup source when power cannot be generated by the wind or sun due to adverse weather, according to the project’s authors. Total investment is expected to be worth EUR 1 billion.

The private endeavour is owned by MCC ekskluzivne nekretnine d.o.o. and Vrdovo reverzibilne hidroelektrane d.o.o., for which a group of Croatian companies is preparing technical and feasibility documentation. The project has seen investments of EUR 5 million and before the location permit the founders expect another EUR 1 million. The project designers finance the documentation and act as de facto co-investors before the introduction of a strategic partner. The companies involved are Elektroprojekt, Energy Institute Hrvoje Požar (EIHP), Energocontrol, Projektni biro Split, Geoprojekt and Geokon Zagreb.

Pumped storage hydropower plant Vrdovo will be built between the north side of the existing Peruća hydropower plant and the natural valley of Ravno Vrdovo. The particular value is in the existing Peruća reservoir and the relatively short distance from Ravno Vrdovo, the vicinity of the power system and a link to the EU electricity system, as well as the small distance from a large number of existing and planned wind and solar power installations, according to information on the project’s website.

Two capacity generators will have the capacity of 270 MW each in turbine mode (power generation) and 245 MW each in pumping mode (storage). The existing accumulation of Peruća plant will be used as the lower pool while the upper reservoir will be built at an altitude difference of about 600 metres. The two reservoirs will be connected by a feed-drain and pressure tunnel. Apart from the upper reservoir, all parts will be built underground, including the link to Hrvace switchyard.

The public consultation about the environmental impact assessment is expected soon. The plan is to prepare a feasibility study by the end of the year, project companies said. The engineering, procurement and construction (EPC) tender and the start of construction is scheduled for 2017, while the gas-powered CHP and transmission line and pipeline may see the beginning of works by 2020. The plan of development estimated the use permit should be obtained by 2022, when Vrdovo hydro facility should be launched.

The combined cycle power plant will be located on the right shore of the Peruća reservoir, about 500 metres upstream from the Peruća barrage, at the site of a former quarry. The value of this location is reflected in the vicinity of the reservoir and water needed for to cool the plant, the relatively short distance from the main pipeline which passes through Dugopolje, the similarly small distance from Konjsko substation, the largest installation in the transmission network in Dalmatia, as well as the nearby high number of existing and planned solar and wind power installations.

Installed production capacity will be 450 MW of electricity and 50 MW of thermal energy. Supply will go through the Hrvace 400/110 kV substation and Hrvace-Konjsko transmission line. The substation will be placed at the highest point.