Energy in numbers - Slovenia

In 2004 27% of electrical energy was produced by hydro power plants. The production of electrical energy in these power plants is highly dependent on hydrological conditions, which results in major fluctuations in production. In 2003 e.g. production at these power plants amounted to only 21% of total electrical energy produced (10).

Wind share of total electricity consumption in Slovenia was 0% by the end of 2010. Overall in the EU, in a normal wind year, installed wind capacity at the end of 2010 meets 5.3% of the EU’s electricity needs (12).

Vulnerabilities Slovenia

Due to the changed snow thawing regime, there will be less water in the spring and in early summer. The potential increase in flows in wintertime may increase production during this season of the year, when demand for electricity is at its peak. The changed water regime may also have effects on the production in thermo power plants, particularly at Krπko nuclear power plant, which even now, in the event of low water levels in the Sava, encounters cooling problems during the summer months. Additionally, difficulties may be expected with specific thermo power plants using wet cooling towers for cooling in relation to the provision of adequate quantities of water (11).

Vulnerabilities Europe

Supply

The current key renewable energy sources in Europe are hydropower (19.8% of electricity generated) and wind. By the 2070s, hydropower potential for the whole of Europe is expected to decline by 6%, translated into a 20 to 50% decrease around the Mediterranean, a 15 to 30% increase in northern and eastern Europe and a stable hydropower pattern for western and central Europe (1,3,4). In areas with increased precipitation and runoff, dam safety may become a problem due to more frequent and intensive flooding events (5).

It has become apparent during recent heat waves and drought periods that electricity generation in thermal power plants may be affected by increases in water temperature and water scarcity. In the case of higher water temperatures the discharge of warm cooling water into the river may be restricted if limit values for temperature are exceeded. Electricity production has already had to be reduced in various locations in Europe during very warm summers (e.g. 2003, 2005 and 2006) (5,8).

Extreme heat waves can pose a serious threat to uninterrupted electricity supplies, mainly because cooling air may be too warm and cooling water may be both scarce and too warm (9).

Climate change will impact thermoelectric power production in Europe through a combination of increased water temperatures and reduced river flow, especially during summer. In particular, thermoelectric power plants in southern and south-eastern Europe will be affected by climate change. Using a physically based hydrological and water temperature modelling framework in combination with an electricity production model, a summer average decrease in capacity of power plants of 6.3–19% in Europe was shown for 2031–2060 compared with 1971-2000, depending on cooling system type and climate scenario (SRES B1 and A2) (13).

Overall, a decrease in low flows (10th percentile of daily distribution) for Europe (except Scandinavia) is projected with an average decrease of 13-15% for 2031–2060 and 16-23% for 2071-2100,compared with 1971-2000. Increases in mean summer (21 June - 20 September) water temperatures are projected of 0.8-1.0°C for 2031–2060 and 1.4-2.3°C for 2071-2100, compared with 1971-2000. Projected water temperature increases are highest in the south-western and south-eastern parts of Europe (13).

By the 22nd century, land area devoted to biofuels may increase by a factor of two to three in all parts of Europe (2).

Demand

It may become more challenging to meet energy demands during peak times due to more frequent heat waves and drought conditions (1). Strong distributional patterns are expected across Europe — with rising cooling (electricity) demand in summer in southern Europe, compared with reduced heating (energy) demand in winter in northern Europe (7).

Adaptation strategies

Due to reduced water flows, especially in periods of drought, in the sphere of energy supply we can expect a smaller contribution from conventional hydroelectric power plants to the daily regulation of production. This is one further reason for re-examining plans to construct pumped storage plants in order to balance daily fluctuations in the consumption of electric power. In addition, the construction must be reconsidered of seasonal accumulation basins for flow enrichment during drought periods for the more balanced production of electricity and for reducing the adverse effects of low flows on river populations. For enhancing the stability of the energy system it is also important to diversify sources, for example by exploiting wind energy (11).

References

The references below are cited in full in a separate map 'References'. Please click here if you are looking for the full references for Slovenia.

1. Lehner et al. (2005), in: Alcamo et al. (2007)
2. Metzger et al. (2004), in: Alcamo et al. (2007)
3. Kirkinen et al. (2005), in: Anderson (ed.) (2007)
4. Veijalainen and Vehviläinen (2006); Andréasson et al. (2006), in: Anderson (ed.) (2007)
5. Anderson (ed.) (2007)
6. Rothstein et al. (2006), in: Anderson (ed.) (2007)
7. Alcamo et al., 2007
8. EEA, JRC and WHO (2008)
9. Behrens et al. (2010)
10. Republic of Slovenia, Ministry of the Environment and Spatial Planning (2006)
11. Republic of Slovenia, Ministry of the Environment, Spatial Planning and Energy (2002)
12. European Wind Energy Association (2011)
13. Van Vliet et al. (2012)