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Number of results: 28
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Abstract

Finite fossil fuel resources, as well as the instability of renewable energy production, make the sustainable management of energy production and consumption some of the key challenges of the 21st century. It also involves threats to the state of the natural environment, among others due to the negative impact of energy on the climate. In such a situation, one of the methods of improving the efficiency of energy management – both on the micro (dispersed energy) and macro (power system) scale, may be innovative technological solutions that enable energy storage. Their effective implementation will allow it to be collected during periods of overproduction and to be used in situations of scarcity. These challenges cannot be overestimated - modern science has a challenge to solve various types of problems related to storage, including the technology used or the control/ /management of energy storage. Heat storage technologies, on which research works are carried out regarding both storage based on a medium such as water, as well as storage using thermochemical transformations or phase-change materials. They give a wide range of applications and improve the efficiency of energy systems on both the macro and micro scale. Of course, the technological properties and economic parameters have an impact on the application of the chosen technology. The article presents a comparison of storage parameters or heat storage methods based on different materials with specification of their work parameters or operating costs.
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Abstract

Dr. Krzysztof Fic of the Poznań University of Technology discusses energy storage, aesthetic medicine’s quest for immortality, and how much time goes into being a scientist.
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Abstract

The aim of the article is a preliminary assessment of the possibility of using ATES (Aquifer Thermal Energy Storage) technology for the seasonal storage of heat and cold in shallow aquifers in Poland. The ATES technology is designed to provide low-temperature heat and cold to big-area consumers. A study by researchers from the Delft University of Technology in the Netherlands indicates very favorable hydrogeological and climate conditions in most of Poland for its successful development. To confirm this, the authors used public hydrogeological data, including information obtained from 1324 boreholes of the groundwater observation and research network and 172 information sheets of groundwater bodies (GWBs). Using requirements for ATES systems, well-described in the world literature, the selection of boreholes was carried out in the GIS environment, which allowed aquifers that meet the required criteria to be captured. The preliminary assessment indicates the possibility of the successful implementation of ATES technology in Poland, in particular in the northern and western parts of the country, including the cities of: Gdańsk, Warsaw, Wrocław, Bydgoszcz, Słupsk, and Stargard.
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Abstract

The utilization of mining waste is an important problem in Poland and Ukraine. The article presents one of the variants of waste mining in the quarry in Płaza. An analysis of the resource base of the deposit and their location at the area of Płaza deposit is carried out. The Płaza deposit is located in the western part of the Małopolskie province, in the entire Chrzanów commune. The Płaza deposit is constructed of Middle Triassic carbonates represented by the limestone-dolomite Olkusz Formation and the limestone-marlized Gogolin Formation. The deposit series lies on the dolomites of Röt age (Lower Triassic – Olenekian). The most valuable raw material was the pure limestone from the lower part of the Olkusz Formation, now almost completely exploited. The article presents the current state of mineable reserves of the deposit and their quality (chemical and physical characteristics). Moreover the article shows potential consumers of raw material and the possibility of extending the life of the mine work. According to the results of the environmental monitoring the ground and hydrogeological conditions were evaluated, the results of which allowed a more efficient use of the existing quarry area for mining waste disposal to be proposed. The paper presents a conceptual waste transport scheme, planned distribution and compaction of wastes belonging to the first, second and third group and then a surface reclamation. In view of the absence of similar decisions analogs, the consideration of the open-pit as a one solid geomechanical system functioning under the conditions of uncertainty is suggested. In order to examine the dynamics of the waste compaction process, some measures are foreseen to constantly observe their subsidence. The proposed measures for the synchronous disposal of mining waste in the worked-out area of the open-pit and the simultaneous mining operation in the quarry will allow the life cycle of the open-pit to be prolonged for 15–20 years.
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Abstract

Increasing the share of energy production from renewable sources (RES) plays a key role in the sustainable and more competitive development of the energy sector. Among the renewable energy sources, the greatest increase can be observed in the case of solar and wind power generation. It should be noted that RES are an increasingly important elements of the power systems and that their share in energy production will continue to rise. On the other hand the development of variable generation sources (wind and solar energy) poses a serious challenge for power systems as operators of unconventional power plants are unable to provide information about the forecasted production level and the energy generated in a given period is sometimes higher than the demand for energy in all of the power systems. Therefore, with the development of RES, a considerable amount of the generated energy is wasted. The solution is energy storage, which makes it possible to improve the management of power systems. The objective of this article is to present the concept of electricity storage in the form of the chemical energy of hydrogen (Power to Gas) in order to improve the functioning of the power system in Poland. The expected growth in the installed capacity of wind power plants will result in more periods in which excess energy will be produced. In order to avoid wasting large amounts of energy, the introduction of storage systems is necessary. An analysis of the development of wind power plants demonstrates that the Power to Gas concept can be developed in Poland, as indicated by the estimated installed capacity and the potential amount of energy to be generated. In view of the above, the excess electricity will be available for storage in the form of chemical energy of hydrogen, which
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Abstract

The aim of this study was to measure the NO level in boar semen held in a liquid state and to determine its putative relation to spermatozoa motility, plasma membrane integrity, mitochondrial membrane potential and ATP content. Generally, the percentage of spermatozoa which generated nitric oxide gradually increased, while NO level in the surrounding medium declined during the liquid preservation. NO generation in semen preserved in BTS was higher as compared to those in Androhep®Plus. We demonstrated the positive correlation between the NO level in fresh spermatozoa and their quality. We also showed negative correlation between nitric oxide level in spermatozoa preserved in BTS and sperm cells motility as well as plasma membrane integrity. Results obtained in this study confirm that NO may affect sperm physiology in a dualistic manner.
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Abstract

This study was executed to investigate the potential of agar-agar, a nontoxic and non-degradable gelling agent, as a promising coating agent to improve and protect banana fruit against fungal postharvest diseases i.e., crown, finger, neck and flower end rots which are caused by fungal isolates of Colletotrichum musae and Fusarium moniliforme. Coated-ba-nana fruit samples with different concentrations of agar-agar suspension particularly at 2.0 g · l−1 exhibited a significant reduction in incidence and severity of postharvest diseases compared to untreated fruit. Banana fruits dipped in agar suspension at 2.0 g · l−1 for 5, 10 and 15 min showed significant reduction in disease incidence and severity. Moreover, application of agar suspension as a coating agent at 2.0 g · l−1 significantly decreased weight loss (%), firmness loss (%), and soluble solid concentration of banana fruit for 15 days at 25 ± 2°C. Scanning electron microscopy observation confirmed that the fruit coated with agar colloid at 2.0 g · l−1 had significantly fewer cracks and showed smoother surfaces than untreated fruit. This explains the quality improvement in agar-coated fruit compared to uncoated fruit. Overall, agar colloid, a safe coating agent, could be used to protect banana fruit against postharvest rot diseases and extend fruit storage life during ripening and storage.
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Abstract

This paper presents a complex study of anhydrite interbeds influence on the cavern stability in the Mechelinki salt deposit. The impact of interbeds on the cavern shape and the stress concentrations were also considered. The stability analysis was based on the 3D numerical modelling. Numerical simulations were performed with use of the Finite Difference Method (FDM) and the FLAC3D v. 6.00 software. The numerical model in a cuboidal shape and the following dimensions: length 1400, width 1400, height 1400 m, comprised the part of the Mechelinki salt deposit. Three (K-6, K-8, K-9) caverns were projected inside this model. The mesh of the numerical model contained about 15 million tetrahedral elements. The occurrence of anhydrite interbeds within the rock salt beds had contributed to the reduction in a diameter and irregular shape of the analysed caverns. The results of the 3D numerical modelling had indicated that the contact area between the rock salt beds and the anhydrite interbeds is likely to the occurrence of displacements. Irregularities in a shape of the analysed caverns are prone to the stress concentration. However, the stability of the analysed caverns are not expected to be affected in the assumed operation conditions and time period (9.5 years).
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Abstract

The article discusses the problem of the supply of a by-product, which is synthetic gypsum produced as a result of flue gas desulphurization in conventional power plants. The state of production and forecast for the future are presented. Currently, synthetic gypsum is almost entirely used as a raw material in the gypsum products plant located in the immediate vicinity of the power plant. Since the mid-1990s, in Poland, an increase in the production of synthetic gypsum associated with the construction of a flue gas desulphurization installation in Polish conventional power plants has been observed. In the near future, the upward trend will continue in connection with the construction of new coal units in power plants. Significant surpluses of this raw material will appear on the market, which will not be used on an ongoing basis in the production of gypsum components. However, due to the EU’s restrictive policy towards energy based on coal and lignite, within the next few decades, the share of conventional power plants in energy production will be gradually reduced. As a consequence, the supply of synthetic gypsum will also gradually decrease. Therefore, it is advisable to properly store the surplus of this raw material so that it can be used in the future. Taking this into account, it is already necessary to prepare methods for storing the expected surpluses of synthetic gypsum. For this purpose, post-mining open pits are particularly suitable, especially in mines of rock raw materials. The article proposes a legal path enabling the post-mining open pits to be transformed into a anthropogenic gypsum deposit.
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Abstract

The article presents the current state of the CNG market used as an alternative fuel for car engines. Attention was paid to European Union directives requirements and the current state of the directives’ fulfillment. The economic aspect of CNG usage was analyzed and the approximate costs of driving 10,000 km on different fuels in the last four years were presented. The PtG process which uses electric energy (hydrogen production) and carbon dioxide captured from the flue gas for the production of synthetic methane were discussed. The scheme of the SNG plant with the indication of its most important components was presented, and attention was paid to the mutual complementation of PtG technologies with carbon dioxide capture technology. The benefits of synthetic methane production are presented and the use of compressed natural gas to power engines in vehicles has been described. First, the focus was on the single-fuel use of CNG in bus and truck engines, paying particular attention to the ecological aspect of the implemented solutions. It has been shown that the use of compressed natural gas will reduce almost 100% of the particulates emission from the combustion process. The advantages and disadvantages of the alternative fuel supply are given. Next, the aspect of dual-fuel use in diesel engines was analyzed on the example of a smaller engine. The degree of reduction of harmful compounds emission from the combustion process is shown. Finally, attention was paid to the possible scale effect, referring to the number of motor vehicles in Poland.
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Abstract

This article considers designing of a renewable electrical power generation system for self-contained homes away from conventional grids. A model based on a technique for the analysis and evaluation of two solar and wind energy sources, electrochemical storage and charging of a housing area is introduced into a simulation and calculation program that aims to decide, based on the optimized results, on electrical energy production system coupled or separated from the two sources mentioned above that must be able to ensure a continuous energy balance at any time of the day. Such system is the most cost-effective among the systems found. The wind system adopted in the study is of the low starting speed that meets the criteria of low winds in the selected region under study unlike the adequate solar resource, which will lead to an examination of its feasibility and profitability to compensate for the inactivity of photovoltaic panels in periods of no sunlight. That is a system with fewer photovoltaic panels and storage batteries whereby these should return a full day of autonomy. Two configurations are selected and discussed. The first is composed of photovoltaic panels and storage batteries and the other includes the addition of a wind system in combination with the photovoltaic system with storage but at a higher investment cost than the first. Consequently, this result proves that is preferable to opt for a purely photovoltaic system supported by the storage in this type of site and invalidates the interest of adding micro wind turbines adapted to sites with low wind resources.
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Abstract

The second decade of the 21st century is a period of intense development of various types of energy storage other than pumped-storage hydroelectricity. Battery and thermal storage systems are particularly rapidly developing ones. The observed phenomenon is a result of a key megatrend, i.e. the development of intermittent renewable energy sources (IRES) (wind power, photovoltaics). The development of RES, mainly in the form of distributed generation, combined with the dynamic development of electric mobility, results in the need to stabilize the grid frequency and voltage and calls for new solutions in order to ensure the security of energy supplies. High maturity, appropriate technical parameters, and increasingly better economic parameters of lithium battery technology (including lithium-ion batteries) result in a rapid increase of the installed capacity of this type of energy storage. The abovementioned phenomena helped to raise the question about the prospects for the development of electricity storage in the world and in Poland in the 2030 horizon. The estimated worldwide battery energy storage capacity in 2030 is ca. 51.1 GW, while in the case of Poland it is approximately 410.6 MW.
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Abstract

We consider the manure removal system, which is used in most pig farms being built and reconstructed at present in Ukraine, and it has been discovered that there are major mistakes during the baths construction in the correct geometry and depth, and therefore discusses their rules of operation. If the baths geometry is wrongly executed, for instance, if the slope is made to slant toward the bottom of the tub filler drain pipe, which in itself is unacceptable, or not properly executed in the form of a special pit steps towards the neck drain, and etc., then a number of problems is inherent of its exploitation. The basic requirements for laying fused-pipe is compliance with its slope. The considered equipment must be equipped with pumping stations to pump manure. The pumps for pumping manure: submersible sewage pumps and dry-installed in the mine and long sewage pumps with electric or PTO shaft of a tractor were analyzed. Attention was paid to the designing of modern equipment for the distribution of manure waste into fractions. The classification of manure storage and the basic requirements for their placement and arrangement was carried out, and recommendations are made for the designing of pumping stations, to select pumps for the pumping stations and the design during the modern construction and reconstruction of old pig farms.
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Abstract

The sustainable management of energy production and consumption is one of the main challenges of the 21st century. This results from the threats to the natural environment, including the negative impact of the energy sector on the climate, the limited resources of fossil fuels, as well as the unstability of renewable energy sources – despite the development of technologies for obtaining energy from the: sun, wind, water, etc. In this situation, the efficiency of energy management, both on the micro (dispersed energy) and macro (power system) scale, may be improved by innovative technological solutions enabling energy storage. Their effective implementation enables energy storage during periods of overproduction and its use in the case of energy shortages. These challenges cannot be overestimated. Modern science needs to solve various technological issues in the field of storage, organizational problems of enterprises producing electricity and heat, or issues related to the functioning of energy markets. The article presents the specificity of the operation of a combined heat and power plant with a heat accumulator in the electricity market while taking the parameters affected by uncertainty into account. It was pointed out that the analysis of the risk associated with energy prices and weather conditions is an important element of the decision-making process and management of a heat and power plant equipped with a cold water heat accumulator. The complexity of the issues and the number of variables to be analyzed at a given time are the reason for the use of advanced forecasting methods. The stochastic modeling methods are considered as interesting tools that allow forecasting the operation of an installation with a heat accumulator while taking the influence of numerous variables into account. The analysis has shown that the combined use of Monte Carlo simulations and forecasting using the geometric Brownian motion enables the quantification of the risk of the CHP plant’s operation and the impact of using the energy store on solving uncertainties. The applied methodology can be used at the design stage of systems with energy storage and enables carrying out the risk analysis in the already existing systems; this will allow their efficiency to be improved. The introduction of additional parameters of the planned investments to the analysis will allow the maximum use of energy storage systems in both industrial and dispersed power generation.
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Abstract

The paper describes factors influencing the development of electricity storage technologies. The results of the energy analysis of the electric energy storage system in the form of hydrogen are presented. The analyzed system consists of an electrolyzer, a hydrogen container, a compressor, and a PEMFC fuel cell with an ion-exchange polymer membrane. The power curves of an electrolyzer and a fuel cell were determined. The analysis took the own needs of the system into account, i.e. the power needed to compress the produced hydrogen and the power of the air compressor supplying air to the cathode channels of the fuel cell stack. The characteristics describing the dependence of the efficiency of the energy storage system in the form of hydrogen as a function of load were determined. The costs of electricity storage as a function of storage capacity were determined. The energy aspects of energy accumulation in lithium-ion cells were briefly characterized and described. The efficiency of the charge/discharge cycle of lithium-ion batteries has been determined. The graph of discharge of the lithium-ion battery depending on the current value was presented. The key parameters of battery operation, i.e. the Depth of Discharge (DoD) and the State of Charge (SoC), were determined. Based on the average market prices of the available lithium-ion batteries for the storage of energy from photovoltaic cells, unit costs of electrochemical energy storage as a function of the DoD parameter were determined.
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Abstract

While modeling water dynamics in dam reservoirs, it is usually assumed that the flow involves the whole water body. It is true for shallow reservoirs (up to several meters of depth) but may be false for deeper ones. The possible presence of a thermocline creates an inactive bottom layer that does not move, causing all the discharge to be carried by the upper strata. This study compares the results of hydrodynamic simulations performed for the whole reservoir to the ones carried out for the upper strata only. The validity of a non-stratified flow approximation is then discussed.
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Abstract

The article presents the analysis of the simulation test results for three variants of the power electronics used as interface between the power network and superconducting magnetic energy storage (SMES) with the following parameters: power of 250 kW, current of 500 A DC and voltage of 500 V DC. Three interface topologies were analyzed: two-level AC-DC and DC-DC converters; three-level systems and mixed systems combining a three-level active rectifier and a two-level DC-DC converter. The following criteria were considered: input and output current and voltage distortions, determined as THDi and THDu, power losses in power electronics components; cost of the semiconductor components for each topology and total cost of the interface. Results of the analysis showed that for high-power low-voltage and high-current power electronics systems, the most advantageous solution from a technical and economical perspective is a two-level interface configuration in relation to both AC-DC and DC-DC converters.
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Abstract

Three commercially available intercooled compression strategies for compressing CO2 were studied. All of the compression concepts required a final delivery pressure of 153 bar at the inlet to the pipeline. Then, simulations were used to determine the maximum safe pipeline distance to subsequent booster stations as a function of inlet pressure, environmental temperature, thickness of the thermal insulation and ground level heat flux conditions. The results show that subcooled liquid transport increases energy efficiency and minimises the cost of CO2 transport over long distances under heat transfer conditions. The study also found that the thermal insulation layer should not be laid on the external surface of the pipe in atmospheric conditions in Poland. The most important problems from the environmental protection point of view are rigorous and robust hazard identification which indirectly affects CO2 transportation. This paper analyses ways of reducing transport risk by means of safety valves.
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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

Leguminous plant products have great nutritional and economic importance in the European Union, which is reflected by its protein policy. These harvested yields are risked by stored product pests, such as Acanthoscelides obtectus Say, which can cause up to 50–60% loss in stored bean items. The bean weevil causes both quantitative and qualitative damage to seeds. We aimed to map the qualitative damage of this devastating pest, which deteriorates the nutritional content of bean kernels. Furthermore, our purpose was to determine accurately the decrease in the volume and density alteration in beans caused by this important stored product pest using CT-assisted imaging analysis. Our results showed that the nutritional arrangement in damaged beans was caused by A. obtectus. The measured nutrient content increment in damaged samples can be explained by the presence of extraneous organic material which originates from perished specimens of the bruchin pest. This is a negative phenomenon in bean items used as forage, because of the loss of valuable proteins and rancidity in herbal oils. Weight loss triggered by developing larvae was 49.42% in examined bean items. The use of 3D technologies has greatly improved and facilitated the detailed investigation of injured seeds. The density (75,834 HU; 41.93%) and the volume (296.162 mm3; 26.21%) values measured by CT of the examined samples were significantly decreased. The decreasing of tissue density in damaged beans can be accounted for by the consumption of starch present at a high ratio and that of the dense reserve components in the cotyledons.
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Abstract

The optimal energy management (OEM) in a stand-alone microgrid (SMG) is a challenging job because of uncertain and intermittent behavior of clean energy sources (CESs) such as a photovoltaic (PV), wind turbine (WT). This paper presents the effective role of battery energy storage (BES) in optimal scheduling of generation sources to fulfill the load demand in an SMG under the intermittency of theWT and PV power. The OEM is performed by minimizing the operational cost of the SMG for the chosen moderate weather profile using an artificial bee colony algorithm (ABC) in four different cases, i.e. without the BES and with the BES having a various level of initial capacity. The results show the efficient role of the BES in keeping the reliability of the SMG with the reduction in carbon-emissions and uncertainty of the CES power. Also, prove that the ABC provides better cost values compared to particle swarm optimization (PSO) and a genetic algorithm (GA). Further, the robustness of system reliability using the BES is tested for the mean data of the considered weather profile.
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Abstract

A short overview of the developments of functional materials featuring miniaturisation and integration is illustrated by examples taken from the ?eld of ceramic functional materials. To obtain new materials new methods are required. Most of them are microfabrication processes developed by the "top-down" approach.
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Abstract

Shoot tips excised from shoot culture of Salvia officinalis were encapsulated in 2% or 3% (w/v) sodium alginate and exposed to 50 mM calcium chloride for complexation. Immediately or after 6, 12 or 24 weeks of storage at 4°C, the synthetic seeds were cultured for 6 weeks on half-strength MS medium supplemented with indole-3-acetic acid (IAA) (0.1 mg/l) and solidified with 0.7% agar. The frequency of shoot and root emergence from encapsulated shoot tips was affected by the concentrations of sodium alginate and additives in the gel matrix (sucrose, gibberellic acid, MS nutrient medium) as well as duration of storage. The frequency of shoot and root induction of non-stored synthetic seeds was highest with shoot tips encapsulated with 2% sodium alginate containing 1.5% sucrose and 0.5 mg/l gibberellic acid (GA3). Shoot tips maintained their viability and ability to develop shoots even after 24 weeks of storage when they were encapsulated in 3% alginate with 1/3 MS medium, sucrose (1.5%) and GA3 (0.25 mg/l). Root formation tended to decrease with storage time. Overall, 90% of the plantlets derived from stored and non-stored synthetic seeds survived in the greenhouse and grew to phenotypically normal plants. This procedure can enable the use of synthetic seed technology for germplasm conservation of S. officinalis, a plant species of high medical and commercial value.
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