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Abstract

Coal mining activities carried out for 200 years in Upper Silesia have had a negative effect on buildings. T his impact is in all cases related with continuous deformations of the surface and in certain cases with discontinuous deformations (mostly cave-ins), changes in water relations and mining tremors. T he paper presents an evaluation of the impact of a mining activity on a building situated in the Upper Silesian Coal Basin. T he building was affected by continuous deformations and mining tremors. Calculations were made of the values of deformation rates by means of Budryk–Knothe’s theory, which were partly verified on the basis of the results from geodetic measurements. An analysis of the velocity and acceleration of basement vibrations caused by mining-induced tremors was also conducted. T he conclusions included a high consistency between the results obtained on the basis of calculations and the values obtained by means of PGA and PGV measurements. In the case of tremors with the highest energy in the hipocentrum, there an empirical formula allowing for calculation of PGA value in given geological and mining conditions was also proposed. T he application range of the formula mentioned above is obviously limited only to the conditions in consideration. The presented conclusions indicate that at present, sufficiently precise methods, allowing for calculations for practical purposes, not only of deformation indices’ values, but also of PGV and PGA values, presently exist.
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Abstract

The article has presented the assumptions underlying the organization of emissions trading of greenhouse gases with a particular emphasis on CO2 emission allowances. Through the analysis of the literature, international activities were undertaken aimed at reducing greenhouse gas emissions into the atmosphere, starting from the First World Climate Conference organized in 1979. The origins and guidelines of the Kyoto Protocol were also given considerable attention. In addition to the description of the key assumptions of the Protocol and its main components, the characteristics of international trade in Kyoto units were also included. The mechanisms involved in international trade and the types of units traded in a detailed manner are described. In the next part of the article, emission trading systems operating in the world are characterized. In the second part of the paper special attention was paid to the conditionings of the European market, i.e. European Emissions Trading System – EU ETS. Historical events were presented that gave rise to the creation of the EU ETS. In the next steps, the types of units that are tradable were described. Furthermore, the trade commodity exchanges on which trade is conducted, the key factors determining the price of individual allowances are also indicated. In the last part of the article, relatively recent issues – the IED Directive and the BAT conclusions have been pointed out. Referring to the applicable regulations, the impact of their implementation on the situation of entities obliged to limit greenhouse gas emissions was analyzed. In the final phase, an attempt was made to assess the impact of IED and BAT to electricity prices.
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Abstract

In this paper, the analysis of carbon footprint values for children’s footwear was conducted. This group of products is characterized by similar small mass and diversity in the used materials. The carbon footprint is an environmental indicator, which is used to measure the total sets of greenhouse gas (GHG) emissions into the atmosphere caused by a product throughout its entire lifecycle. The complexity of carbon footprint calculation methodology is caused by multistage production process. The probability of emission greenhouse gases exists at each of these stages. Moreover, a large variety of footwear materials – both synthetic and natural, give the possibility of the emission of a lot of waste, sewage and gases, which can be dangerous to the environment. The diversity of materials could be the source of problems with the description of their origins, which make carbon footprint calculations difficult, especially in cases of complex supply chains. In this paper, with use of life cycle assessment, the carbon footprint was calculated for 4 children’s footwear types (one with an open upper and three with full uppers). The life cycles of the product were divided into 8 stages: raw materials extraction (stage 1), production of input materials (stage 2), footwear components manufacture (stage 3), footwear manufacture (stage 4), primary packaging manufacture (stage 5), footwear distribution to customers (stage 6), use phase (stage 7) and product’s end of life (stage 8). On these grounds, it was possible to point out the life cycle stages, where the optimization activities can be implemented in order to reduce greenhouse gases emissions. The obtained results showed that the most intensive corrective actions should be focused on the following stages: 3 (the higher emissivity), 4 and 8.
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Abstract

The large variability and unpredictability of energy production from photovoltaic power microinstallations results from the dependence on the current weather conditions. These conditions depend on a number of factors and are variable over the time. Despite this specificity, photovoltaic micro-installations are becoming more and more popular in the world and in Poland. This is mainly due to the fact that the generation of energy from renewable sources has numerous advantages, the energy is free, renewable in time and ecological, and its production on its own gives partial independence from energy supplies from the power grid. In addition, the observed significant prices decrease of solar modules has further accelerated the development of the use of this energy source. Concern for this method of energy production among households has increased significantly in Poland after introducing the prosumer in the legal framework and the use of administrative and financial support. The implemented prosumer mechanisms allowed, for example, the net balancing of the energy consumed and produced by the micro-installation through storage in the power grid. The article describes the problem of balancing sources using solar energy, based on micro-installation used in the household (the so-called prosumer installation). The conducted analyses compared the load profile of a typical household and the energy generation profile from a photovoltaic installation, determining the real balancing formation level of such a system.
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Abstract

The Polish energy sector is, to a large extent, based on fossil fuels used in conventional energy, which is not entirely consistent with the current energy policy of the European Union. Therefore, it is necessary to increase the use of renewable energy sources that guarantee the preservation of the value of the natural environment in rural areas. It should be emphasized that in addition to the economic effect, the environmental effect is very important, understood as the impact of renewable energy on the natural environment and the quality of life of rural residents. The intensive development of RES raises a lot of controversy among politicians, as well as among rural residents, who are also associated with the myths regarding renewable energy as harmful to the natural environment. Rural development should be connected with the socio-economic situation, and even more so with the socio-cultural situation of its inhabitants, because it assumes that the development of rural areas in Poland is associated not only with agriculture, but also with historical and natural values and their durability. The aim of this work is to determine the attitudes of the inhabitants of rural areas of the Podkarpackie Province on the impact of renewable energy sources on the natural environment. The work assumes that the durability of rural areas is largely connected with the ability to preserve their natural values, as well as ensuring a satisfactory quality of life for residents. The basic source of data was surveys carried out in 2017 among 282 inhabitants of the Podkarpackie Province .
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Abstract

The development of electromobility is a challenge for the power system in both technical and economic-market terms. As of today, there are no analyses to determine the power necessary to supply the planned infrastructure and to estimate the incentives and economic benefits resulting from the modification of the settlement method. The document determining the legal regulations and the obligation to build vehicle charging stations for specific municipalities is the Act on Electromobility and Alternative Fuels. This act estimates that the development of electromobility, due to the specifics including not only individual vehicles, will take place in certain areas. The places which in the first stage will be dedicated to the potential implementation of the concept of electromobility will be municipalities covering large agglomerations. In addition, due to the local aspect, the development of electromobility may take place in the areas of energy clusters’ initiatives, which, using the policy of increasing energy awareness, are aimed at energy production from local renewable energy resources. The planned development of electromobility assumes a systematic increase in the number of electric cars caused by the introduction of support systems. The dynamization of this sector will cause an increase in the demand for electricity. Due to power system reasons, an important factor determining the level of energy consumption depending on the time of day may be an appropriate shape of the pricing for the charging service. Appropriate price list stimulation can affect the behavior of recipients, causing the charging of cars in the off-peak of electricity demand. The aim of the article is to characterize the scale of the phenomenon of electromobility in the context of the emergence of a charging points infrastructure along with the possibility of price-setting stimulation affecting the profile of energy demand. It is also important to consider the challenges and responsibilities of municipalities and energy clusters from the perspective of introducing electromobility.
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Abstract

The aim of this article is to present the author’s opinion about possible underwater natural gas pipeline monitoring using Polish Navy resources. Due to the bathymetrical characteristics of the pipeline equatorials the high efficiency and safe for the deck operators systems are expected to support the bottom survey and gas line monitoring. Time and engaged resources reduction are crucial factors in this kind of mission together with high probability of possible dangerous objects detection. The paper describes main threats for the underwater transportation line as a state energetic independence vital object (supplies diversification). An example of a threat caused by lost unmanned platform technologies near Nord Stream was presented and analyzed as well. The rapid development of unmanned maritime technologies (aerial, surface and subsurface) observed in the last decade creates new possibilities in maritime security/surveillance applications. The Polish mine counter measures assets which were equipped with sophisticated AUV’s as a part of the Polish Navy modernization process (new minehunters Kormoran IInd class deployable). The presented autonomous underwater vehicles (AUV) are equipped with advanced sonars and create new possibilities in the issue of effective threats detection/classification/ identification and neutralization. The main advantages of such solutions were pointed in the article with the crucial one based on time reduction as well as human – deck operators threats constraints. The first successes in the operational use of unmanned systems were reached during the military exercises (historical ordnance disposal) conducted on historical mine laying areas. This creates good possibilities to train the unmanned system operators in live objects activity which improves skills and knowledge. Moreover, the double use applications of unmanned technologies both in defense and maritime security has been observed.
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Abstract

Recently, the search for new effective energy production solutions has been focused on the production of electricity using renewable and environmentally friendly carriers. This resulted in an increased interest in PV cells and cogeneration systems. The article looks at the main factors affecting their operational parameters against the background of the development history of subsequent generations of PV cells. Average daily solar radiation and wind velocity in Lodz were characterized. The research was done on a static and tracking system with a total peak power of 15 kWp and a 30 kW microturbine. PV panels are installed on the building of the Institute of Electrical Power Engineering of the Lodz University of Technology and they work as part of DERLab. A microturbine is inside the building. Energy measurements were carried out in 2016 giving grounds for the analysis of energy efficiency and financial analysis of the energy supply in buildings. Energy yields in the static and tracking system as well as percentage coverage of electricity from PV cells and microturbines were assessed. The distribution of monthly savings, annual savings of energy costs and the payback time of the investment costs of the systems subject to the test were determined. The research we have done allows us to say that the energy produced by follow-up modules is about 3 times greater than that generated in stationary modules. On the other hand, the annual savings of energy costs using gas micro-turbines are about 10 times higher than those of lagging panels. The analysis shows that it is possible to determine the profitability of the microturbine and photovoltaic panels use despite large financial outlays. The payback period of investment outlays is about 12 years when using the installation throughout the year.
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Abstract

This publication presents an assessment of the economic efficiency of a hypothetical installation for the gasification of the municipal and industrial waste for the production of syngas used subsequently for the production of energy or chemical products. The first part of the work presents an example of a technological system for the energo-chemical processing of coal mud and municipal waste, based on the gasification process using a fluidized bed reactor. A hypothetical installation consists of two main blocks: a fuel preparation unit and a gasification unit. In the fuel preparation installation, reception operations take place, storage, and then grinding, mixing, drying and transporting fuel to the gasification unit. In the gasification installation, fuel gasification, oxygen production, cooling and purification of raw process gas and ash treatment are carried out. The following key assumptions regarding the gasification process, as well as the capital expenditures and operating costs related to the process, were estimated. Consequently, based on the method of discounted cash flows, the unit cost of generating energy contained in the synthesis gas (cost of energy, COE) was determined and the results were interpreted. In order to obtain an acceptable efficiency of the gasification process for waste fuels for the production of alternative fuel (process gas), it is necessary to supplement the mixture of waste coal and coal mud with the RDF. In this case, the unit cost of fuel measured by the PLN/GJ index is lower than in the case of hard coal and comparable with brown coal. The use of coal mud for the production of process gas in an economically efficient way is possible only in the case of changes in the legal system allowing for charging fees for the utilization of industrial waste – coal mud.
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Abstract

Fractal analysis is one of the rapidly evolving branches of mathematics and finds its application in different analyses such as pore space description. It constitutes a new approach to the issue of their natural irregularity and roughness. To be properly applied, it should be encompassed by an error estimation. The article presents and verifies uncertainties along with imperfections connected with image analysis and expands on the possible ways of their correction. One of key aspects of such research is finding both appropriate place and the number of photos to take. A coarse- grained sandstone thin section was photographed and then pictures were combined into one, bigger image. Fractal parameters distributions show their change and suggest that the accurately gathered group of photos include both highly and less porous regions. Their amount should be representative and adequate to the sample. The resolution influence on the fractal dimension and lacunarity values was examined. For SEM limestone images obtained using backscattered electrons, magnification in the range of 120x to 2000x was used. Additionally, a single pore was examined. The acquired results point to the fact that the values of fractal dimension are similar to a wide range of magnifications, while lacunarity changes each time. This is connected with changing homogeneity of the image. The article also undertakes a problem of determining fractal parameters spatial distribution based on binarization. The available methods assume that it is carried out after or before the image division into rectangles to create fractal dimension and lacunarity values for interpolation. An individual binarization, although time consuming, provides better results that resemble reality to a closer degree. It is not possible to define a single, correct methodology of error elimination. A set of hints has been presented that can improve results of further image analysis of pore space.
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Abstract

The paper presents the characteristics of the attitude that students have towards electric cars and the significance of distinguished attitude elements in creating interest in the purchase of such vehicles. Electric cars are the new type of vehicles that have an electric motor and use the electricity stored in batteries. They are introduced to the market, but for various reasons the volume of sales is not high. So far, it is not sufficiently known how electric vehicles are assessed by Poles. The presented research is an attempt to know what the attitude towards this type of vehicle. The attitude model tested in this research includes three areas: knowledge about them, emotions that they evoke and potential behaviors. The participants were students of Rzeszów University of Technology – a group of young people who are potential consumers of new technologies. The obtained results indicate that electric cars are rather unknown. At the same time, they arouse great interest and their image is very positive. The attitude characteristics towards this type of vehicle is supplemented by perceived limitations: too high of a purchase price, lack of sufficient information about them and unsatisfactory technical parameters, mainly the long time needed to recharge the battery and the insufficiently long distance with one recharge. The interest in the purchase is dependent on positive emotions, and the lack of sufficient information is an obstacle in thinking about buying such a vehicle. Understanding the attitudes of Polish students towards electric cars can be helpful in adapting information about such cars to potential customers, which in turn may affect the level of interest and sales volume.
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Abstract

Mining-induced seismicity, particularly high-energy seismic events, is a major factor giving rise to dynamic phenomena within the rock strata. Rockbursts and stress relief events produce the most serious consequences in underground mines, are most difficult to predict and tend to interact with other mining hazards, thus making control measures difficult to implement. In the context of steadily increasing mining depth within copper mines in the Legnica-Głogów Copper Belt Area (Poland) alongside the gradually decreasing effective mining thickness, a study of the causes and specificity of mining-induced seismicity in specific geological and mining settings may improve the effectiveness of the prevention and control measures taken to limit the negative impacts of rockbursts in underground mine workings, thus ensuring safe working conditions for miners. This study investigates the presumed relationship between the mined ore deposit thickness and fundamental parameters of mining-induced seismicity, with the main focus on the actual locations of their epicenters with respect to the working face in commonly used room-and-pillar systems. Data recalled in this study was supplied by the O/ZG Rudna geophysics station. Based on information about the actual ore deposit thickness in particular sections of the mines (Rudna Główna, Rudna Północna, Rudna Zachodnia) and recent reports on seismic activity in this area, three panels were selected for further studies (each in different mine region), where the ore deposit thickness was varied (panel G-7/5 – Rudna Główna, panel XX/1 – Rudna Północna, panel XIX/1 – Rudna Zachodnia). Data from seismic activity reports in those regions was used for energetic and quantitative analysis of seismic events in the context of the epicenter location with respect to the selected mining system components: undisturbed strata, working face and abandoned excavations. In consideration of the available rockburst control methods and preventive measures, all events (above 1 × 103 J) registered in the database were analysed to infer about the global rockburst hazard level in the panel and phenomena induced (provoked) by blasting were considered in order to evaluate the effectiveness of the implemented control measures.
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Abstract

On May 17, 2018, the National Center for Research and Development announced the initiation of a new procedure within the Hydrogen Storage Program. The objective was to develop a Hydrogen Storage System for use with fuel cells and its demonstration in a Mobile Facility. This is to create an alternative to the use of fossil fuels and create a field for competition in creating solutions in the field of access to “clean” energy. The National Center for Research and Development is responsible for the development of assumptions, regulations and implementation. The analysis presents the main assumptions of the program is correlated to the current legal situation related to the financing of Research and Development. An in-depth study concerns the ways of using innovative partnership and its placement in the system of European Union legal acts. The idea of the pre-commercial procurement procedure (Pre-Commercial Procurement), which was developed to support the implementation of prototypes of solutions – resulting from research and development – with a high potential for possible commercialization, was described in details. This procedure is characterized by ensuring the financing of a product or service at an early stage of development. Although this creates the risk of failure of the project, it stimulates technological development.
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Abstract

It is estimated that the amount of used car tires in the European Union in 2016 was established at the level of 3,515,000 Mg, which is undoubtedly a problem from the point of view of engineering and environmental protection. An alternative to storing this waste in landfills is their pyrolysis. As a result of thermal decomposition, calorific value products (oil and gas fraction) are obtained, as well as a solid residue, which due to its composition and properties can be processed into a high quality carbon sorbent. For this purpose, various methods of modification of the pyrolyzate are used, both involving physical and chemical activation. This article presents the characteristics of solid residue after the pyrolysis of rubber tires running at a temperature of about 400°C, which included an analysis of chemical composition (XRF and IR), mineralogical composition (XRD, SEM-EDS) and textural characteristics. Additionally, for the purpose of activation, the sample was treated with nitrogen at a temperature of 550°C. The mineralogical analysis showed that the dominant mineral component is carbon. In addition, the presence of quartz, calcite and sphalerite was observed. Analysis of the chemical composition suggests that due to the high carbon content (about 80% by mass) it is possible for a carbon sorbent from the analyzed waste to be obtained. However, previous preliminary studies did not allow a material constituting a substitute for activated carbon to be obtained, because the applied modification only slightly increased the BET specific surface area, which reached the value of approx. 85 m2/g. Based on the analysis of the pore size distribution of the 2 tested samples, it was found to be homogeneous/modal with a micro/mesoporous nature, while the shape of the hysteresis loop suggests the presence of “bottle shape” pores. Due to the relatively high content of zinc, the composition of waste (about 4% of mass), the possibility of recovery of this element should also be considered.
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Abstract

By means of small wind turbines, it is possible to create distributed sources of electricity useful in areas with good wind conditions. Sometimes, however, it is possible to use small wind turbines also in areas characterized by lower average wind speeds during the year. At the small wind turbine design stage, various types of technical solutions to increase the speed of the wind stream, as well as to optimally orientate it, can be applied. The methods for increasing the efficiency of wind energy conversion into electricity in the case of a wind turbine include: the use of a diffuser shielding the turbine rotor and the optimization of blades mounted on the turbine rotor. In the paper, the influence of the diffuser and rotor blades geometry on the efficiency of an exemplary wind turbine for exploitation in the West Pomeranian Province is investigated. The analyses are performed for three types of the diffuser and for three types of rotor blades. Based on them, the most optimal shapes of the diffuser and blades are selected due to the efficiency of the wind turbine. For the turbine with the designed diffuser, calculations of the output power for the assumed different values of the average annual wind speed and the constant Betz power factor and the specified generator efficiency are made. In all the analyzed cases, the amount of energy that can be generated by the turbine during the year is also estimated. Important practical conclusions are formulated on the basis of these calculations. In the final part of the paper, a 3D model of the wind turbine with the diffuser and rotor blades chosen based on earlier analyses is presented. As a material for the diffuser and rotor blades, glass fiber type A is applied. By means of calculations using the finite element method, the limit displacement of the turbine structure under the influence of a hurricane wind are determined. Based on these calculations, the correctness of the modelled small wind turbine structure has been demonstrated.
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