Wind energy is an excellent example of how renewable energy production is not new in recent decades. On the contrary. People have been using renewable energy sources such as wind, water, or biomass for centuries. Simple forms of windmills were discovered in Persia and date back to around 200 BC. During the Middle Ages, wind energy was used intensively, for example in the territory of today's Spain. The windmill system was improved in America, in the 19th century, more than 6 million small windmill-based machines were used to pump water. The first wind turbines to produce electricity were created in Scotland in 1887. Significant wind electricity production took place in the last century, mainly in Europe and the USA, while production technology was constantly improving and streamlining.
The wind farm operates on the principle of converting wind energy into electricity. The key part of the machine is the rotor. It rotates at a height of 100 - 200 m using the wind and drives an electricity generator. The rotor can have several shapes, but the most typical are propellers. The efficiency of the wind power plant is max. 59.3% (currently achieving an efficiency of around 34%). With technological progress, the output of wind turbines also increases (up to 12 MW). Wind turbines are getting higher, and the blade span can now reach up to 100 m. The wind speed also increases with height, so the height of the tube is important. At an altitude of over 150 m, the potential for wind electricity production in Slovakia is significantly higher than at the time when the pilot project for the construction of VE was launched in Slovakia. At that time, the turbines reached a height of about 80 m.
If Slovakia wants to achieve the highest possible share of RES in electricity production, it is important to combine photovoltaics and wind energy, because they complement each other. When the sun shines there is often no wind, and vice versa, when the wind blows, the sky is overcast.
In 2019, wind energy accounted for an average of 15% of electricity production in the EU-28. In the case of the Slovak Republic, it is not even 1%, which, together with Slovenia we have the smallest share of wind energy in electricity production in the EU. However, Slovenia has a geographically low wind energy potential, so it is no surprise that it is on the tail end in this ranking. Like Slovakia, the Czech Republic and Hungary also have a share of 1% and 2%. In Poland, on the other hand, VE accounts for 9% and in Austria, it is as high as 13%. Of the V4 countries, Poland has the most significant faith potential. Slovakia has similar weather conditions as Austria, but it is far ahead of us in the construction of wind turbines. It is therefore not true that wind energy has no future in our country. Our 0% share of VE in electricity generation is probably for political rather than geographical reasons.
Slovak energy policy has in the past provided for the development of wind power plants. According to the National Energy Action Plan for RES from 2010, 350 MW wind farms were to be installed by 2020. In 2020, however, Slovakia has only 4 turbines installed with a total output of 3.14 MW. There are currently 2 wind farms in operation - Myjava Wind Farm, Ostrý Vrch (0.5 MW) and Cerová Wind Park (2.64 MW), both owned by the WEON Group. Together they produce 6 GWh of electricity per year. The National Energy and Climate Plan (INECP) declares an increase in output from VE to 500 MW by 2030, which would represent approximately 1,200 GWh of energy per year. However, this plan is likely to need to be stepped up in the context of the EU's targets based on the Fit for 55 package of measures to combat climate change.
The development of wind energy in Slovakia must take place in a sustainable way so that we could effectively achieve the goals of Slovak climate policy while minimizing the negative impact on the environment and the country. You can read more about the sustainable development of RES in Slovakia in our document Criteria for the Sustainability of RES, on which SAPI worked within the Slovak Climate Initiative, of which we are a member.
Myth: Wind energy is expensive
If the energy market were completely deregulated and there was no system of subsidies and state financing, wind energy would be one of the cheapest technologies for electricity generation. Subsidies for renewable energy in Europe are only a fraction of the subsidies that go to coal, nuclear or gas power plants. After the support for the producer of RES ends, it sells electricity at market prices. It should be emphasized that the generation of electricity from wind does not result in any waste in the form of radioactive waste, exhaust gases or wastewater. Such operation is therefore significantly more environmentally efficient and safer. This does not generate incidental costs for the disposal of production waste.
Myth: The construction of wind turbines hurts the local economy
Wind energy can contribute to the development of the local economy in the form of local taxes that the producer must pay. At the same time, if the future wind farm should stand on private lands, such as a field, the landowner will agree with the developer on a form of payment for the use of the land. Such a lease of land for the construction and operation of a wind turbine (s) is advantageous for the owner, as the wind farm does not take up a large area and the owner can continue to use the land for agricultural purposes on the remaining land. While this may sound surprising, wind turbines can have a positive effect on local tourism. Especially in a country where wind turbines are more of a rarity.
Myth: There is no interest in wind energy in Slovakia
According to a public opinion poll commissioned by SAPI, 68% of Slovaks surveyed are in favor of using wind energy in Slovakia. Only 8% of respondents oppose wind turbines. This means that Slovaks see a greater future in wind power generation than in fossil fuel power generation.
Myth: The wind structure is disturbing, its appearance and especially its height aesthetically disrupts the character of the landscape
The experience of the inhabitants of Austria, where they have over a thousand wind turbines, is definitely positive. According to local surveys, 2/3 of the residents living near wind turbines are satisfied and do not state that the turbines would interfere with them or that they would otherwise negatively affect the quality of life.
Myth: Infrasound generated by wind turbines can have a negative impact on human health. Wind turbines are noisy, their sound is disturbing.
Infrasound, ie the sound spectrum in the very low frequency, which is below the threshold of human hearing, are common in nature (wind, surf). Infrared sound is created by buildings or appliances as in this respect, several studies have been carried out, and adverse effects on the human body have not been proven.
Modern wind turbines, despite their mast height (150m - 200m) are relatively quiet. Of course, in high winds, noise is increased. The volume of operation of the wind turbine is monitored and before the construction itself, several noise simulations are performed, when the sound of the turbine is added to the natural and already existing noise of the given environment. In Slovakia, we have strict noise limits, and the wind project must pass an environmental and health impact assessment, so it is not possible to create a wind farm that violates the limits.