ISSN 1805-3386

April 10, 2020


2018 No.4

Analysis of Transients during the Power System Restoration

Eleschová, Ž., Jedinák, M., Šmidovič, R.

The paper presents simulation results of transients during the power system restoration. The Defence plan and Restoration plan development is a part of transmission system operator’s responsibilities and requires thorough calculations, simulations and publication of instructions. The plans focus on extensive failures that have a heavy impact on the system operation and could lead to a blackout. The Restoration plan of power system has to contain procedures for start-up without outside help. TSO regularly checks some part of the Restoration plan.


Keywords: restoration, black-start, restoration route, auxiliary systems, transients.


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Biogas Stations in Slovakia – Current State

Janíček, F., Perný, M., Šály, V., Némethová, J.

The paper focuses on the use of biomass in the conditions of the Slovak Republic. The importance and position of biomass within renewable energy sources is highlighted in the introduction. Documents such as laws, studies, and strategies which have been developed with the aim to increase the share of renewable energy sources within the energy mix are listed here. The issue of biogas and its possible sources in the Slovak Republic was also solved. An important part of the paper is the presentation of the current statistical data concerning to the number of biogas stations and also information about the material used for gasification purposes in SR. A separate part of the contribution consists of the field research results focused on selected biogas stations in western Slovakia. We provide basic technical specifications, biomass suppliers and statistical data about heat and electricity production for each station. Selected stations were located in villages: Smolinské, Malý Cetín, Ružindol, Chynorany and Kolíňany.


Keywords: renewable energy sources, biomass, fermentation, gasification, anaerobic digestion, waste recovery


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The Digestate: A Nutrient Source for the Alternative Biomass for Anaerobic Digestion

Gaduš, J., Głowacka, N.

Construction of new biogas plant stations in Europe is a steadily growing trend, that is the reason why there is a need to find a proper alternative source of energy, which can replace traditional crops used for generation of energy. Microalgae represent a high potential of energy. When comparing microalgae with traditional crops, we can point out their high potential (oil content). During the production of biogas from traditional input materials, it is still a great potential of resulting organic waste – fermentation water (digestate), which can be used in a closed cycle in the intensive year-round cultivation of microalgae. Using the by-product (digestate) generated during the process of anaerobic digestion we can create a system for the cultivation of microalgae, which will in turn be used as a raw material for the biogas plant. Thanks to such application, the biogas plant can be more ‘selfsufficient’. This new innovative process can provide a prerequisite scale for increasing commercial use of bioenergy from microalgae. However, there is a need to find a reasonable way to produce the algae biomass to meet all ecological and economic requirements.


Keywords: digestate, microalgae, anaerobic digestion, circular economy.


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Legal Aspects of Electricity Produced from RES in SR

Gaduš, J., jr., Giertl, T.

The paper deals with the promotion of the use of RES in the area of electricity production in Slovakia. To promote the use of RES for electricity generation a system of subsidies as well as exemptions from the excise duty on electricity produced from RES have been introduced. The most important support mechanism for the use of RES in Slovakia in general, and within the field of electricity production from RES, are the feed-in tariffs. They are very effective and easy to implement, but carry certain risks. However, in 2016 the share of RES in gross final energy consumption dropped compared to previous year so the government prepared some amendments to the law.


Keywords: drenewable energy sources (RES), electricity production, support mechanism systems, feed-in tariffs, amendment.


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