Sun - the ultimate energy source on the Earth (Courtesy of SOHO consortium. SOHO is a project of international cooperation between ESA and NASA.)

Slovak Republic depends at 90% on the import of primary energetical raw materials such as natural gas, crude oil, coals or nuclear fuel. At present, an output of 7 095,41 MW is installed in Slovakia.

The output composition of the Slovak Electric Power Plants’ resources is as follows:

This composition contributed considerably to the air pollution drop during the last years. E. g., the emission from the installed capacity dropped from 235 000 tons of SO₂ in 1980 to the current 70 000 tons, i. e. the Slovak Republic met the target SO₂ emission for the year 2010, to which it has been obliged by its accession to the Rio de Janeiro Protocol, as early as 1995.

NUCLEAR POWER PLANTS - UNDER RECONSIDERATION

Slovak nuclear power-plants in Mochovce and Bohunice are of the VVER. Similar reactors have been in operation in Dukovany in the Czech republic, in Paks in Hungary, as well as in Slovenia and Finnland. In the Mochovce power plant, the upgraded eastern technology and western safety systems have been combined successfully.

Mochovce nuclear plant

In the recent years, SO₂, NO_x, solid particles and CO ceased to be the most problematic pollutants from the global point of view, as contrary to CO₂ and ozone in the near-surface atmosphere. Also Slovak Republic has committed itself in Kyoto to cut CO₂ emission by 8% in the period from 2008-2012 compared to 1990. But in case, that instead 2x400 MW of the nuclear wattage installed in Mochovce, a coal-fired power plant should generate the same amount of electricity, the annual CO₂ production would surge by six million tons - which means a 12% increase compared to the current situation.

Experts, who prepared the study “Slovak Republic’s options for reducing CO₂ emission” with the support of the Swiss government, the Slovak environment ministry, the World Bank and USAID in March 1998, consider expanding the use of the nuclear potential for generating electricity as one of the options available.

An effective support for the utilisation of renewable and secondary energetical resources such as wood/bio-mass (abundant), geothermal (available), solar (limited), wind (limited) is among the priorities in all developed countries across the world. The current share of the renewable energy resources in covering the overall energy consumption in the EU represents 5,3%. In Slovakia, that yearly share is currently 3,8%, i.e., 28 875 TJ of energy. Until 2010 the share in the EU is supposed to increase to 12%.

However, a real development of such environment friendly resources will be possible only on the assumption that the state takes relevant legislative and economic steps in support of this strategy (state subsidies, soft credits, realistic electricity pricing, tax reliefs, home-based facilities and equipment production).

HYDROELECTRIC PROJECT GABČÍKOVO

The project was realised by the Vodohospodárska výstavba, state owned company based in Bratislava. In spite of the fact that the case whether Slovakia had the right to carry through its part of the project or not after Hungary withdrew from the mutual contract was resolved by the International Court in the Hague, we would like to offer a less judicial view on this matter.

The intake structure Dobrohošť feeds Danube's arms system with water (max. 350 m3 s-1). Photo: P. Áč

This multipurpose hydroelectric project was drawn together with Hungary, according to the interstate treaty signed in 1977. It was designed as a part of the Gabčíkovo-Nagymaros System, located on the Danube River downstream of Bratislava, the capital of Slovakia. Among the project goals originally prevailed flood protection due to devastating floods that would occur in the adjacent area and electricity production. Only later environmental views were included in the process of project planning and implementation. Under the pressure developed by conservationists, a unique system of intake structures was designed in order to preserve the Danube inland delta.

The inland delta - a pristine ecosystem featuring intact floodplain forests - was threatened not only by the original plans that did not consider environmental criteria sufficiently. The riverbed of the Danube had been sinking since the fifties also due to the construction of water reservoirs and dams on the upper stream of the Danube, both on German and Austrian territories. The stream velocity went down and so did its ability to carry gravel and sand necessary to offset riparian erosion of the riverbed. In fact, these materials were deposited in reservoirs instead and subsequently excavated. This process resulted in sinking of the ground water level and the water surface in the old riverbed. Therefore, flood plain forests gradually declined because root systems of their trees were unable to extract water from ground water and from dead branches remaining out of reach of the sinking water surface in the old riverbed.

Nowadays, the hydroelectric project Gabčíkovo secures sufficient water supply of the delta through a sophisticated water management and a system of intake structures and transversal barrages that conduct water into the inland delta and retain it there when necessary. Another problem is, however, that the content of nutrients in water is low after sedimentation in the water reservoir. This problem will have to be solved somehow in order to secure the sustainability of such a sensitive ecosystem.