Search

The method of infrared thermography was used in this paper to identify over-heated areas inside module of hydrogen fuel cells. This module fitted with polymer proton exchange membranes, is a part of a laboratory off-grid system that serves to storage of electricity gained from photovoitaic panels. Hydrogen is not an energy source but a storage medium and an energy carrier. Hydrogen module operation with insufficient cooling can lead to its overheating and destruction. The cause of this undesirable state is detected here by the help of computer simulation using suitable numerical model. An appropriate solution to this problem is proposed to allowed a more efficient and safe operation of this module of hydrogen fuel cells.

Renewable energy sources are becoming more and more widespread and practical used, but it is difficult to plan and stabilize the process of obtaining and storing this kind of energy. The hydrogen like an energy carrier is a possible decision for stable energy storage. Thanks to the hydrogen solid state storage systems based on metal hydrides is possible to store the energy, comes from renewable sources under safety and easy conditions. Historical methods of hydrogen storage like compression and liquefaction, which are established and developed now, still bring big safety problems and associated high costs of compression and cooling.

The paper deals with utilization of a photovoltaic power plant, installed on the roof of buildings within the Technological Centre in Ostrava (TCO) for production of hydrogen through electrolysis of water. The hydrogen produced will be stored in pressure vessels and used as fuel in fuel cells. The whole system of electrolysers for hydrogen production, pressure vessels for its storage and fuel cells for regenerating of electric power serve for storage of power supplied by the photovoltaic power plant and these are situated within the hydrogen technologies laboratory at TCO. The paper provides a brief description of specifications of photovoltaic panels and inverters, with further assessment of the power supply during the year 2016, enumeration of the amount of hydrogen that could be produced using the power supplied.

This article discusses rechargeable stations for electric vehicles. Deals with the current infrastructure, assumed progress of electro mobility, estimated amount of electric energy required for charging of electric vehicles. There are analyzed topics such as methods of charging of batteries in electric vehicles, basic concept of charging station. Also is included practical measurement on a small charging station in the region of Ostrava.

This paper presents very small laboratory hybrid photovoltaic-hydrogen power system. The system was primarily assembled to verify the operability of the control algorithms and practical deployment of available commercial hydrogen technologies that are directly usable for storage of electricity produced from renewable energy sources in a small island system. This energetic system was installed and tested in Laboratory of fuel cells that is located in the university campus of VSB-Technical University of Ostrava. The energetic system consists of several basic components: a photovoltaic field, accumulators bank, water commercial electrolyzer and compact fuel cell system. The weather conditions recorded in two different weeks as model weather and solar conditions are used as case studies to test the energetic system and the results for two different cases are compared each other. The results show and illustrate selected behaviour curves of the power system and also average energy storage efficiency for accumulation subsystem based on hydrogen technologies or at the energetic system embedded components. On the basis of real measurement and its evaluation the ideal parameters of the photovoltaic field were calculated as well as the hydrogen technologies for supposed purpose and the power requirements.

The paper deals with consideration of potential means for control of electric output within a 22kV network using co-generation units cooperating with a photovoltaic power plant. The contents include comparison of individual methods for control of electric output using a co-generation unit with the output rating for 1 MW. The methods subject to comparison will include single-, two-, multi-stage and dynamic control. Particular method of control will be applied to a specific case of daily chart showing the load of 22kV network.

This paper deals with a description and partial analysis of energy production units and their implementation in the laboratories of ENET technological centre in Ostrava - Vitkovice. The paper refers to individual types of conventional and non-traditional sources of electric power that are connected to the technological centre distribution grid, together with analysis of their topological configuration, with a presentation showing division of individual power sources into logical technological groups with definition of either nominal or estimated operating parameters. The data summarised in this paper will serve mainly as input material to design a dynamic model, for modelling of transients and short-circuit ratios mainly on non-traditional energy sources, as well as full energetic systems already implemented. That is why the paper also addresses an introduction of concept and expected software products for future creation of the model.

The paper deals with utilisation of infrared thermography in the field of hydrogen fuel cells currently being implemented both in stationary and mobile applications. Completed thermovision measurements are used for evaluation of heating curves of particular type of fuel cells represented by the low-temperature cells with a proton exchange membrane (PEM). These cells form part of the experimental power system designed for research on storage of electric power gained from renewable energy sources with an unstable power supply. This system is operated in the Laboratory of fuel cells at VSB - TU Ostrava.

Biogas stations have become a significant renewable energy source over the recent years. Renewable energy sources are often characteristic for their unpredictable operation and they cause problems within the distribution network. That was why we focused on measurement conducted on a specific biogas station with evaluation of its operation. The measurement ran for two months and involved the automatic measuring gauge ENA 330. The values obtained by measurement were used for evaluation of courses, mainly for output and voltage. The results indicate a certain voltage imbalance, however, it still complies with the applicable standards. Further section deals with spectra of harmonics at higher levels. Those also comply with the standard CSN EN 50 160. The current procedure in progress deals with identification of their potential sources and options for their elimination. This paper forms a part of a long-term research process.

The paper describes the equipment and utilisation of the hydrogen technology laboratory included within the newly developed ENET technological centre for research of renewable energy sources and storage of electric power. The essential fittings of this laboratory comprise electrolyzers for production of hydrogen from de-mineralised water using electric power generated by photovoltaic panels, together with fuel cells for reverse production of electric power from the stored hydrogen.

The technology of fuel cells and mainly the solid oxide fuel cells (SOFC) is still subject to a fairly intense development for its unforgettable competitive advantage, the opportunity to use relatively cheap and accessible hydrocarbon fossil fuels or other synthetic fuels containing hydrogen molecules. These fuel cells are mainly intended for application in power systems for combined production of electric power and heat (co-generation) or for an additional production of electric power to improve the energetic balance of other power technologies. Technologies proven through experiments and procedures employed in production of SOFC fuel cells have shown sound operating parameters during laboratory testing and these will be prepared for application into actual power equipment within a medium-term horizon, for gradual commercialisation and even preparation for serial production, according to some optimistic perspectives. The contents of this paper should bring a closer look onto the technology of fuel cells, the SOFC type fuel cells respectively, their basic topology, operating principle and the last but not the least would be the presentation of procedures implemented in application and results of testing of a specific prototype design of a high-temperature tubular SOFC fuel cell.

This paper describes the technological centre for research of renewable resources and accumulation of electric power that forms a part of the scheme ENET - Energy Units for Utilization of Non-Traditional Energy Sources. The centre will operate several systems for production and accumulation of electric power. One of them is a pyrolyzing unit for generation of gas from solid waste materials, which will be used further as fuel for engine driving the synchronous generator. Another source of power comprises photovoltaic panels installed on the building roof. Accumulation of electric power supplied by these sources is ensured by the power storage bank and hydrogen technology using electric power for generation of hydrogen by means of water electrolysis, storage of such hydrogen in pressure vessels and its re-use for production of electric power in fuel cells. All the power produced or accumulated can be used to cover the internal consumption of technological centre as well as for supply into the public low voltage distribution grid.

This paper deals with accumulation of electric power by means of hydrogen technology and reverse transformation of such power stored in hydrogen into electric power again. The crucial part of this paper comprises calculation of efficiency achieved by accumulation of power into hydrogen, including the efficiency of individual components forming the accumulation (storage) system located in the fuel cells laboratory of VSB - TU Ostrava. The source of renewable energy in this system is represented by a small photovoltaic power plant feeding the hydrogen generator - electrolyzer as the main appliance for reverse chemical transformation together with hydrogen fuel cells. Both of these appliances operate at low temperature, they are based on PEM (Proton Exchange Membranes) technology. The electrolyzer ensures decomposition of purified water to oxygen and hydrogen by action of direct electric current. The fuel cell houses a reverse process, when chemical reactions between hydrogen and oxygen are electric power of water result in production of electric power and water.

This paper focuses on biogas plants with combined heat and power production and their impact on line voltage. It provides a description of a specific biogas plant subject to a longer measurement. The description reveals the course of measurement followed by essential statistical data pertaining to selected values. Further indicators include bar charts for voltage showing a certain asymmetry in the grid and describing the distribution of individual voltage readings obtained by measurement. The main body of this paper further contains the regression model of voltage established by the statistical software that describes characteristics of voltage in the grid with respect to the electric current supplied. The dependence of voltage on current implied by the model is fairly low.

This paper elaborates on the hydrogen technology with respect to electrical power accumulation in hydrogen via Hogen GC600 electrolyzer. Further details will include options for storage of hydrogen into containers currently available. The measurements contained in the paper illustrate laboratory research of hydrogen generation in the electrolyzer which are being taken at the Fuel Cells Laboratory, VSB-Technical University of Ostrava. The matter comprises research on impact of changes to parameters of this electrolyzer on efficiency of gaseous hydrogen production. Electric power needful for the electrolyzer supply is delivered from photovoltaic panels.

With regards to their high effectiveness in transformation of input energy of chemical bonds into the output electric and heat energy and environmental friendly nature, fuel cells have been addressed with great potential prospective. There are various installations of large stationary sources in all over the globe, with unit output of megawatts and these are based on the fuel cells principle. The current development in this field aims towards the increase in efficiency on transformation of fuel energy into the output energy. This paper describes basic characteristics PEM (Proton Exchange Membrane) type fuel cells. Those are low-temperature fuel cells, which are currently commonly used in broad range of applications both in the field of stationary or mobile assemblies. This paper is linked to another one, which deals with the effect of fuel parameters on the efficiency of transformation of energy from chemical bonds into utilisable electric and heat energy as well as the quality of energy supplied.

The fuel cells laboratory at the VSB-TUO have recently finished the realisation of the laboratory energetic system for accumulation of electric power from renewable energy source (with varying and unreliable production process). This system comprises of two parts. The first part of the system, which this paper deals, is about hydrogen production using the electric power from photovoltaic panels and its storage. The other part of the system uses fuel cells to transform the energy from hydrogen into electric power.

Using solar energy in photovoltaic power plants is an important method of electricity generation from renewable sources. Its potential is vast and technically easy to utilise. In the period of 2009 and 2010, photovoltaic power plants were the fastest-growing renewable energy source in the Czech Republic. Their installed capacity reached 487 MWp (January 2010). Only in the last year more than 1000 MWp was put in operation. Based on that it can be expected that by the end of 2011 the total installed capacity of photovoltaic power plants in the Czech Republic could exceed 2000 MWp. This rapid development of photovoltaic sources is having a negative effect on the electric power systems control.

With regards to their high effectiveness in transformation of input energy of chemical bonds into the output electric and heat energy and environmental friendly nature, fuel cells have been addressed with great potential prospective. There are various installations of large stationary sources in all over the globe, with unit output of megawatts and these are based on the fuel cells principle. The current development in this field aims towards the increase in efficiency on transformation of fuel energy into the output energy. This paper deals with the effect of fuel parameters, especially its temperature, pressure and humidity, on the efficiency of transformation of energy from chemical bonds into utilisable electric and heat energy as well as the quality of energy supplied. This paper is conveniently supplemented by another paper from by the same authors, describing basic characteristics of the PEM (Proton Exchange Membrane) type fuel cells.

The MCA8 supportive software was developed mainly for the purpose of the support of multi-criteria decision making in the field of electrical power engineering. The MCA8 offers six methods of multi-criteria analysis (MCA) for solving extensive multi-criteria decision making tasks. We can use this MCA8 software for comparison of the systems for storage of electrical energy gained from non-regulated renewable energy sources (RES). The problem with these sources, including wind and photovoltaic power plants, is their back-up. Storing the energy from these sources is an important precondition for the uninterrupted supply of electricity to consumers.

At present, photovoltaic (PV) power plants are the fastest-growing renewable energy source in the Czech Republic. This rapid development of PV sources is having a negative effect on the electric power system control. One option for mitigating this effect is to store the energy generated by PV in times of excess power in the grid and supply it to the grid when required, i.e., during peak periods of the daily load curve.

This paper describes the MCA8 - the supportive software application for computation of six methods of multi-criteria analysis (TOPSIS, CDA, AGREPREF, WSA, PROMETHEE and IPA). These methods have been implemented to the MCA8 on the basis of the type of real decision-making tasks solved in the field of electrical power engineering. We can use them for example for selecting the most suitable old electrical devices in electrical distribution networks, which we need to replace by a new devices, which fall under the system of remote control and monitoring networks. The application of these remote-controlled devices causes acceleration in handling and thus shortening of duration of a fault in the electrical networks. This results in rising of probability of faultless service and thus the reliability of electrical energy supply. We cannot replace all old devices, because the price of these devices is very high. The MCA8 software application may be used to selecting the most suitable variants. The MCA8 is determined for solving decision-making problems not only in the field of electrical power engineering.

This paper deals with the legislative framework amending supply of electricity. It outlines an analysis of the important quality parameters of electricity supplied by small hydropower stations in the waterworks buildings in practice.