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Generation of photovoltaic power plants is growing rapidly in the last ten years in the world. One of the key factors for the construction of floating photovoltaic power plants is to provide space for their construction. This paper presents statistical indicators of installed capacities of floating photovoltaic power plants, as well as a detailed description of the components of these power plants. Approaches to construction and maintenance recommendations are described in more detail. The basic results of simulations are presented on a concrete example of a floating photovoltaic 1 MW power plant on Lake Modrac. The available areas of artificial lakes in Bosnia and Herzegovina were analysed, and it was shown that the installation of floating photovoltaic power plants on 5% of the surface of artificial lakes would provide around 10% of the total electricity consumption in Bosnia and Herzegovina. [ABSTRACT FROM AUTHOR]

The paper discusses the threat of decommissioning to the thermal power plant (TPP) heat exchanger tubes because of erosion and develops a computer-integrated control system (CICS) for the process of distribution of steam coal flows with different indicators of abrasive materials content, which is based on fuzzy logic. The problem of rapid decommissioning of TPP heat exchangers, particularly abrasive damage to furnace screen tubes, economizer, superheater, etc. This may indicate a discrepancy between the expected fuel ash content and the actual one, as well as a high content of abrasive impurities in steam coal. The work aims to develop a CICS of the wear resistance of the heat exchange surface of a steam boiler of a coal-fired power plant by measuring and fuzzy control of the content of abrasive impurities in steam coal. The problems of damage to the equipment of the TPP boiler are investigated, and a system for controlling the wear resistance of the surface by automatic fuzzy control of the quality of coal is developed. The results were investigated during coal preparation and combustion in the furnace of a thermal power plant to investigate the effectiveness of the proposed fuzzy controller. The model results confirm the feasibility of the fuzzy control method for the system with different coal quality parameters. [ABSTRACT FROM AUTHOR]

In this paper, the research progress of ammonium bisulfate (ABS) volatilization in coal-fired power plants the SCR denitrification process was reviewed. Combination with self-made experiments, SEM, flue gas analyzer and TG-DTG curves of ABS and ion chromatography. The volatilization and condensation characteristics of ABS were investigated carefully. Results show that as the temperature increased by 50 oC, the ABS/AS volatilization rate increased by an order of magnitude. The decomposition process of ABS should have a two-step reaction. The reaction in the initial volatiliza-tion stage is ABS dehydration turned into (NH4)2S2O7. The reaction in the rapid volat-ilization stage is (NH4)2S2O7 decomposed into NH3, N2, SO2 and H2O. There is an inter-section in the reaction temperature range (especially 300 oC) between the two-step re-action. This research provides an experimental basis for temperature control of ABS to avoid air pre-heater fouling. [ABSTRACT FROM AUTHOR]

The electricity sector in Europe and in the world is undergoing rapid and profound changes. There is a sharp increase in the capacity of renewable energy sources, coal and nuclear power plants are being closed and new technologies are being introduced. Especially rapid changes are taking place in the energy systems of the Baltic States. Under these conditions, there is an emerging need for new planning tools particularly for the analysis of the power system properties in a long-term perspective. The main contribution of this article lies in the formulation and solution of optimization problems that arise when planning the development of power systems in the Baltic States. To solve this problem, it is necessary to use models of various power plants and make a number of assumptions, the justification of which requires the following actions: to briefly review the current situation of the production and demand of energy in the Baltic power systems; to conduct an overview of the Baltic interconnections and their development; to make forecasts of energy prices, water inflow, energy production and demand; to set and solve the problems of optimization of power plant operation modes; to demonstrate the possibility and limitations of the developed tools on the basis of real-life and forecast data. In this paper, a case study is performed using the main components of the overall modelling framework being developed. It focuses on the Baltic power systems in 2050 under the conditions of significant expansion in the installed capacity of renewable energy sources (RESs) and diminished fossil fuel power plant activity. The resulting electricity generation mix and trade balance with neighbouring countries is assessed, showing that even with significant RES expansion, the Baltic countries remain net importers and because of the intermittency of RESs, there are hours within the year when the demand cannot be met. [ABSTRACT FROM AUTHOR]

The paper investigates the effect of the carbon tax on the optimal parameters and indicators of two coal power plants: a steam turbine power unit with coal dust burning in a steam boiler and an internal gasification combined cycle power plant. Sufficiently detailed mathematical models have been developed for the considered plants that are focused on calculating the flow rates of working fluids and coolants and thermodynamic parameters at all points of the flowcharts, as well as the structural characteristics of the plant elements. The problems of optimizing the parameters of these plants related to the problems of nonlinear mathematical programming are formulated. As an efficiency criterion, the price of electricity is used at given value of the internal rate of return on investment. Optimization calculations were carried out with a carbon tax in the range from 0 $/t to 140 $/t in increments of 20 $/t. It is shown that with an increase in the charge for emissions, the optimal efficiency of the plants increases, as well as the specific investment. Specific CO2 emissions are reduced. Throughout the entire range of carbon tax values, IGCC power plant has the best economic and environmental indicators. [ABSTRACT FROM AUTHOR]

Water infiltration through coal stocks exposed to weather elements represents a key issue for many old mining sites and coal-fired power plants from the environmental point of view, considering the negative impact on human health of the deriving groundwater, soil and air pollution. Within this context, the paper investigates the hydraulic behaviour of a self-weight compacted unsaturated coal mass and its impact on the numerical prediction of infiltration induced by rainfall events. In particular, the work focuses on the experimental investigation carried out at different representative scales, from the grain scale to physical modelling. The material, when starting from uncompacted conditions, seems to be characterized by metastable structure, which tends to collapse under imbibition. In addition, direct numerical predictions of the seepage regime through a partially saturated coal mass have been performed. As the compaction of the coal stock induced by dozers has not been taken into account, the numerical simulations represent a conservative approach for the assessment of chemical pollution hazard associated to water infiltration into a real stockpile under operational conditions. [ABSTRACT FROM AUTHOR]

In this paper short-term planning algorithm for hybrid power system consist of different types of cascade hydropower plants (run-of-the river, pumped storage, conventional), thermal power plants (coal-fired power plants, combined cycle gasfired power plants) and wind farms is presented. The optimization process provides a joint bid of the hybrid system, and thus making the operation schedule of hydro and thermal power plants, the operation condition of pumped-storage hydropower plants with the aim of maximizing profits on day ahead market, according to expected hourly electricity prices, the expected local water inflow in certain hydropower plants, and the expected production of electrical energy from the wind farm, taking into account previously contracted bilateral agreement for electricity generation. Optimization process is formulated as hourly-discretized mixed integer linear optimization problem. Optimization model is applied on the case study in order to show general features of the developed model. [ABSTRACT FROM AUTHOR]

The purpose of this article is to demonstrate possibilities of mixing coal with biomass using static mixers. The paper present simple and inexpensive methods for producing fuel mixes for heat-generating plants equipped with stoker-fired boilers of power ranging from 3 up to 50 MW. Static mixer proposed in this article may constitute an alternative for currently used solutions in production facility. Based on statistical analysis, the article demonstrates that five mixing elements of the mixer is optimal number to ensure best biomass (chips and pellets) concentration distribution in a mixture with fine hard coal. [ABSTRACT FROM AUTHOR]

By coal burning in coal power plants result a lot of gases that leads to a chemical pollution of environment. The gases resulted in coal burning have a complex impact over the atmosphere, soil and water. Atmosphere pollution with SO2 is very harmful to flora and fauna. Considering that in coal burning result chemical substances that are very harmful to flora and fauna, a purification of coal before burning is asserted, especially by reduction of sulphur content. The purpose of this paper is to bring in front a coal desulphurization process based on dealkalization with the help of Na2CO3 diluted solution in presence of oxygen under pressure. [ABSTRACT FROM AUTHOR]

The usefulness of 2 methods for biomonitoring of the effects of land rehabilitation were compared in Pszów (Upper Silesian Coal Basin, south of Poland). Thirty-one species of mesostigmatid mites were collected from 3 study plots representing different stages of restoration of the mine dump Wrzosy in Pszów and community structure of the mites was analysed. There was a general trend for mesostigmatid species richness, diversity, and density to increase with the development of vegetation. The dominant early successional mesostigmatid species was the phoretic Hypoapis claviger. During this study, 4616 specimens of soil microarthropods were extracted in total. They were classified according to the Biological Soil Quality Index (QBS). We tested the sensitivity and usefulness of this index for monitoring of soil quality and found its good relationship with successional stages in the reclaimed mine dump. Thus the QBS index seems to be an efficient index for monitoring the effects of restoration in mine dumps. It is a simpler, quicker, and cheaper bioindicator method than the earlier method based on community structure analysis of mesostigmatid mites. [ABSTRACT FROM AUTHOR]

The authors analyze the applicability of the Nord Pool Spot (NPS) prices of Finland to the electricity market of Latvia, and, consequently, the appropriateness of using the electricity forwards from NPS for price estimates in Latvia. They propose a concept of electricity price regulation for public supply in Latvia based on the price forecasts of NPS forward contracts taking into account the cross-border congestions. Additionally, good correlation has been obtained between the marginal costs of a coal-fired power plant and the electricity forwards for the Finland's NPS area. [ABSTRACT FROM AUTHOR]