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The use of fossil fuel-based energy systems that provide heat and electricity to a building has adverse environmental impacts. These impacts can be mitigated, to a certain extent, through the incorporation of renewable energy sources (RES). The primary objective of this study was to conduct an environmental assessment of the performance of energy systems in existing public facilities located in Poland. Based on the findings, we proposed and implemented changes to these systems and validated the environmental impact of the RES systems used. SimaPro 8.1 software and the Ecoinvent 3.0 database were employed for the analysis, which entailed an environmental assessment of six public facilities located in Poland. The installation of RES resulted in an average 27% reduction in electricity consumption from the national electricity grid. This reduction was observed to be the least in the hospital and the most in the religious building. This was reflected in the environmental assessment of heating systems. The implementation of RES reduced the environmental impact of the religious building by an average of 20%. Concurrently, the CO2 emissions decreased by 35%, SO2 by 44%, and PM10 by 42%. Significant investments and the installation of advanced RES will not prevent the occurrence of unintentional environmental consequences unless the demand for electricity and thermal energy is reduced. The use of RES in the analyzed buildings and the associated avoided emissions do not entirely offset the negative emissions resulting from the utilization of other (conventional) energy sources in the analyzed energy systems of public buildings. Consequently, the analyzed facilities collectively exert a detrimental impact on the environment. [ABSTRACT FROM AUTHOR]

This work presents an economic analysis of the use of electricity storage in PV installations, based on previously adopted assumptions, i.e., the type and location of the tested facility and comparative variants, divided into the share of the storage in the installation, and the billing system. The work takes into account the share of the energy shield and assumes a consumption limit of 2000 kWh. The cost of building the installation is based on July 2023 prices. The work assumes potential directions of changes in electricity prices, based on which the degree of investment profitability for a given price situation is determined. Depending on the adopted change in the direction of electricity prices, with a low price increase rate, for installations in the new billing system (net-billing), the optimal choice is an installation without energy storage with a power exceeding the actual energy demand. Assuming a high increase in electricity prices, the optimal choice is an installation with energy storage with an installation capacity exceeding the actual demand. For installations billed using the net-metering system, the optimal choice is an installation without storage with an appropriately selected installation power. This article shows how much you can gain after installing a PV installation and not only what costs must be incurred to complete the investment. Profit analysis will enable a more complete assessment of the profitability of investing in PV panels (with or without energy storage). It describes the verification of the profitability of a PV installation for a standard user depending on various types of settlements with the electricity supplier and the lack or installation of an energy-storage facility. [ABSTRACT FROM AUTHOR]

This study evaluates a hybrid heating system in a single-family building in northeastern Poland, which has a temperate continental climate. The analysis covers two heating seasons in 2021/2022 and 2022/2023. The hybrid heating system includes an air heat pump HPA–08 CS Plus with a heating power of 8.2 kW (AHP), a condensing gas boiler VC146/5–5 with a power of 14 kW (GB–Condens.), and a solid fuel boiler with a power of 11 kW for central heating. Additionally, hot water is heated by a Basic 270 (DHW's AHP) air–water heat pump with a power of 2 kW, utilizing a tank with a capacity of 270 dm3 equipped with two heating coils. The building's average electricity consumption is around 5400 kWh/year. A 4.96 kWp photovoltaic installation is installed on the building's roof at a 40° angle towards the south to supplement the hybrid system. The study aims to assess whether the PV installation can adequately cover the energy needs of the hybrid heat source for heating and hot water. Furthermore, the study calculates the emission of pollutants (CO2, SOx, NOx, CO, and PM10) into the atmosphere. The total annual electricity production from PV installations was 5444.9 kWh in 2021/2022 and 5684.8 kWh in 2022/2023. The excess electricity was stored in the PGE power grid as per the Prosumer settlement rules. The installed PV installation is sufficient to power the following devices annually: AHP, DHW's AHP, and GB–Condens. However, the daily electricity production from the PV installation is not enough to cover the energy needs of the heat pump for heating during the cold months in Poland (I–III, XI–XII). It can meet the power needs of a PC all year round and can also be stored during the summer months, for example, in energy warehouses or by directly storing it in the PGE power grid. The use of the PV installation resulted in an average reduction in pollutant emissions into the atmosphere: CO2—94.1%, SOx—91.8%, NOx—95.6%, CO—9.7%, and PM10—32.1%. [ABSTRACT FROM AUTHOR]

Traffic signal priority issues have been a research subject for several decades in Poland and worldwide. Traffic control algorithms have evolved considerably during this period and have become increasingly advanced. Most of them operate within coordinated street sequences, which adds to their complexity. Tramway priority affects traffic conditions for other road users, so many aspects must be taken into account when choosing a priority solution. Typically, one of the main criteria for evaluating the effectiveness of priority is reducing travel time for the priority vehicle while ensuring that the travel times of other traffic participants through the intersection are maintained or slightly deteriorated. However, the energy aspects are often overlooked. This publication aims to investigate how local priority for tramways in traffic signals of coordinated streets affects energy consumption for tramway traction needs. The study was conducted using a microscopic modeling method with PTV Vissim software (ver. 2021). The models were built for coordinated sequences with different levels of priority. Real traffic control algorithms with priority were implemented into the model on the sequence of Marymoncka Street and Grochowska Street in Warsaw. Then, by introducing changes to the parameters of the algorithms, their effect on traffic characteristics, including estimated power consumption, was studied. The results obtained from the computer simulation were statistically processed using R software (ver. 4.3.2). The analysis results prove the effectiveness of tramway priority operation, show its impact on electricity consumption, and allow us to determine the limits of its effective application. Thus, they complement the knowledge of the impact of tramway priority on traffic. The research results also have practical value, as they help us to make rational decisions in the process of designing traffic control algorithms at intersections with a multi-criteria approach. [ABSTRACT FROM AUTHOR]

The buildings sector is the single most important end-user of final energy in the European Union and a significant contributor to carbon and greenhouse gas emissions. This work focuses on a review of available data that are used to calculate the annual emissions from electricity generation in the European Union and quantify indirect emissions from the use of electricity in the buildings sector. Historical data since 1990 are used to derive simple empirical correlations for the time evolution of emissions factors related to electricity production in each Member State of the European Union. More recent trajectories using data from the last ten years are also presented. The derived correlations can be easily integrated in building stock modeling and national studies to facilitate forward-looking projections of emissions from electricity use in buildings. The EU-27 averages 0.2883 kgCO2-eq/kWhel, ranging from 0.0456 kgCO2-eq/kWhel in Sweden up to 1.0595 kgCO2-eq/kWhel in Poland. As a case study, the derived coefficients are then used to quantify the indirect emissions from the electricity consumption attributed to the building stock in each EU Member State. The calculated total EU-27 GHG indirect emissions attributed to electricity consumption amounted to 215 MtCO2-eq for residential buildings and 201 MtCO2-eq for non-residential buildings. In addition, the proposed correlations are used to demonstrate how they can be used for more realistic future projections of emissions towards the national targets in Greece and Poland. [ABSTRACT FROM AUTHOR]

Fruit and vegetable processing comes 6th in terms of energy consumption in the agri-food industry. At the same time, 88.4% of the industry's final energy consumption structure is thermal energy, which depends heavily on electricity consumption. In addition, fruit and vegetable processing has a significant impact on the environment due to consumption of significant amounts of water. Reducing these three indicators simultaneously would increase the efficiency of the process while improving environmental protection. This paper proposes neural models of thermal energy, electricity and water consumption for selected major fruit- and vegetable-processing plants in Poland. These models were the basis for formulating a multi-criteria optimization task. Optimization of thermal energy, electricity and water consumption was carried out using genetic algorithms. The optimization results in the sense of Pareto can be the basis for the use of sustainable technology in selected fruit- and vegetable-processing plants. [ABSTRACT FROM AUTHOR]

This study assessed hourly electricity consumption profiles in railway signal boxes located in Poland. The analyses carried out consisted of assessing the correlation among the hourly demand profile, weather indicators, and calendar indicators, e.g., temperature, cloud cover, day of the week, and month. The analysis allowed us to assess which indicator impacts the energy consumption profile and would be useful when forecasting energy demand. In total, 15 railway signal boxes were selected for analysis and grouped according to three characteristic repeatability profiles. On this basis, six of the signal boxes and one that did not fit into any of the groups were selected for further analysis. Four correlation research methods were selected for analysis: Pearson's method, Spearman's method, scatter plots, and distance covariance. The possibility of forecasting electricity consumption based on previously aggregated profiles and determining correlations with indicators was presented. The given indicators vary depending on the facility. Analyses showed different dependencies of the electricity demand profile. The ambient temperature and time of day have the greatest impact on the profile. Regarding the correlation with temperature, the results of the Pearson's and Spearman's coefficients ranged from approximately −0.4 to more than −0.8. The highest correlation coefficients were obtained when comparing the demand profile with the previous day. In this case, the Pearson's and Spearman's coefficients for all analysed objects range from approximately 0.7 to over 0.9. [ABSTRACT FROM AUTHOR]

Copyright of Przegląd Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Forecasting electricity demand is of utmost importance for ensuring the stability of the entire energy sector. However, predicting the future electricity demand and its value poses a formidable challenge due to the intricate nature of the processes influenced by renewable energy sources. Within this piece, we have meticulously explored the efficacy of fundamental deep learning models designed for electricity forecasting. Among the deep learning models, we have innovatively crafted recursive neural networks (RNNs) predominantly based on LSTM and combined architectures. The dataset employed was procured from a SolarEdge designer. The dataset encompasses daily records spanning the past year, encompassing an exhaustive collection of parameters extracted from solar farm (based on location in Central Europe (Poland Swietokrzyskie Voivodeship)). The experimental findings unequivocally demonstrated the exceptional superiority of the LSTM models over other counterparts concerning forecasting accuracy. Consequently, we compared multilayer DNN architectures with results provided by the simulator. The measurable results of both DNN models are multi-layer LSTM-only accuracy based on R2—0.885 and EncoderDecoderLSTM R2—0.812. [ABSTRACT FROM AUTHOR]

In the face of ongoing climate changes and the current geopolitical situation, Renewable Energy Sources (RES) are continuously gaining popularity in many countries. Objectives related to environmental protection and the use of RES set by different countries all over the world, as well as by the European Union (EU), are becoming priorities for many. The increase in the installed capacity of photovoltaic systems has been growing steadily for several years, leading to the creation of new systems accompanying PV installations; this phenomenon has also been observed in Poland. This paper presents a photovoltaic system in the form of a bicycle shed next to a school building as an example of building-integrated photovoltaics (BIPV) without connection to the power grid. It was shown that the energy consumption profile should be properly correlated with the production profile, otherwise significant losses occur. Alternative methods to improve the correlation of production and energy consumption by using SCADA systems or building automation to properly manage the electricity generation and consumption installation were also proposed. Furthermore, it was shown that adopting a fixed discount rate in financial analyses can distort the picture of real profits. An analysis of the changes in the NPV ratio using variable discount rates was carried out when analyzing the entire life of the solar plant. [ABSTRACT FROM AUTHOR]

During the dewatering process, centrate is produced, which is returned to the beginning of the technological system. The quality of the resulting centrate, and therefore the size of the returned load of pollutants, affects the demand for electricity in the process of biological wastewater treatment. The following study presents the results of centrate quality tests at five wastewater treatment plants located in Poland. The dependence between suspended solids content and ammonia and COD concentrations in the centrate was determined. It was estimated that an increase in the overall suspended solids leads to an increase in COD by about 1.15 kgCOD/kgTSS. No correlation was found between TSS concentration and ammonia. It was calculated that the complete elimination of suspended solids from the sludge would reduce the electricity consumption for all five objects by about 535 MWh/y. [ABSTRACT FROM AUTHOR]

Purpose: Electrical energy is in this day and age fundamental to the functioning of every household. The use of gas, heating oil or solid fuels for home heating also involves the supply of electricity. Today, electric power is the most environmentally friendly source of energy. Experience has shown that substitution of an oil heating system with a heat pump resulted in significant financial savings for the household. Design/methodology/approach: The purpose of this paper shall entail the construction of a multi-equation econometric model describing the mechanisms of electricity consumption in a specified household. The model takes the nature of a system of interdependent equations. Described shall be the monthly volume of electricity consumption, payment amount of for this energy (in PLN), and price per 1 MWh in a given month. Monthly time series from September 2015 to November 2022 have been used, which resulted in a time series with a count of 87 statistical observations. Findings: The econometric model of household electricity consumption presented in this paper confirms both the hypothesis about feedback between the variables USAGE and PRICE as well as the recursive effect of electricity consumption volume on its value in monetary units. In addition to the cognitive value of the econometric modeling results obtained, the empirical tool constructed makes enables forecast estimation of the energy consumption volume, its value and unit price in subsequent months, for at least 12 consecutive months. Practical implications: This type of research has great practical utility. They make it easier for rational interaction between electricity sellers and specific consumers. Social implications: Knowledge about the mechanisms of electricity consumption on the farm home may influence the rationalization of consumption and spending. This type of rationalization should have a positive impact on the environment natural, contributing to the reduction of greenhouse gas emissions. Originality/value: The novelty and originality of the work are the identification of the mechanism behavior of a single household consuming energy electric. Feedback between magnitudes revealed electricity consumption and its price on a specific farm home. The recipients of the work will be electricity sellers, consumers, and researchers of household market behavior. [ABSTRACT FROM AUTHOR]

The globally increasing trend of fossil fuel consumption has culminated in a historical degradation of the environment and the rising threat of global warming. Researchers and policymakers aim at examining critical relationships between energy productivity and environmental degradation to make recommendations for global policy action. This paper aims to capture the effect of energy productivity on environmental degradation in Poland from 1990Q1 to 2019Q4, using novel Fourier-bases ADF unit root and Fourier-based ARDL approaches. First, outcomes of the Fourier ARDL bounds test indicate that variables are integrated; second, outcomes of the Fourier ARDL long-run estimates indicate that (i) energy productivity has long-run negative effects on CO2 emissions; and (ii) economic growth, globalization, and primary energy consumption have positive effects on CO2 emissions. Among the options available to Polish policymakers are (i) liberalizing domestic energy markets to offer an opportunity for electricity consumers to switch companies and (ii) continuing to pursue a policy of decarbonizing energy supply by investing heavily in renewable energy, nuclear power, e-mobility, and energy productivity. [ABSTRACT FROM AUTHOR]

Currently, the Stabilized Organic Fraction (SOF) 0–80 mm separated from the municipal waste stream is sent in its entirety to landfill in the mechanical-biological treatment plants operating in Poland. Such action does not align with the adopted EU strategy focused on waste management in the circular economy. This study aimed to assess the technical feasibility of the process of purification of mineral fractions with a grain size of 10–80 mm separated from SOF on a technological installation designed for glass recovery, built at the Marszów Plant. In terms of material, mineral fractions are a mixture of stones, rubble and glass, contaminated with various components, mainly organic. In 2020, the glass recovery installation was expanded with an innovative process of gravity separation to separate mineral fraction from SOF with the use of a jigging machine. A pulse jig used in the mining industry for coal enrichment processes was used for the first time in municipal waste management. The installation allows for the recovery of between 71.1 and 96.6% of mineral fractions contained in the input (84.8 ± 9.5% on average). The proportion of organics, plastics and other impurities in the waste is 4.1 ± 2.1% of the fraction mass. The process consumed water at an average rate of 0.34 ± 0.10 m3 tonnes−1 of treated waste and generated 0.26 ± 0.09 m3 tonnes−1 of wastewater. Electricity consumption averaged 1.20 kWh tonne−1 input. [ABSTRACT FROM AUTHOR]

The aim of this study was to assess the energy consumption of production in selected branches of the food industry in Poland and to identify its changes after Poland's accession to the EU. This issue is particularly important in the period of energy transformation and soaring energy prices. The novelty of this article is the determination of changes in the energy efficiency of various branches of the food industry. The main source of data was mass statistics data and unpublished data from the Central Statistical Office for 2004–2020. Descriptive statistics, comparative analysis, and strategic group mapping were used in the data analysis. The research shows that the production of foodstuffs is one of the most energy-intensive processing sectors. This results, among others, from many active enterprises in this sector and a large variety of industries. Individual food-processing industries are characterized by large differences in the energy consumption of production, which determines the different levels of electricity costs and affects the competitiveness of enterprises. In 2004–2019, the average electricity consumption in the food industry in Poland decreased by 31.5%. A greater increase in the value of sold production compensated for the higher energy consumption. This indicates an improvement in production efficiency and contributes to greater environmental protection. In the food sector, simple comparative advantages disappear in the form of lower production costs. This situation encourages processing companies to look for energy savings. The research results can be useful not only in Poland but also in other countries in shaping economic policy. The energy crisis caused by the war in Ukraine may require different actions to be taken against various sectors of the food industry. [ABSTRACT FROM AUTHOR]

Fossil fuels, which are widely used in Poland, have negative environmental and health consequences. Photovoltaics, used especially by households, contribute to a reduction in CO2 emissions and indirectly reduce the problem of smog. However, the high cost of photovoltaic installations forces the use of economic incentives, such as direct subsidies to the installation, under the "My Electricity" program (hereinafter referred to as the program). The development of photovoltaics is hindered by the ineffective functioning of transmission grids. In the current edition of the "My Electricity" program, the main emphasis was placed on the use of electricity at the place of generation through the use of energy storage facilities and the transition to a new billing system, so-called net billing. The program indirectly contributes to the growing popularity of heat pumps as an installation that uses electricity generated on-site. Significant changes in the program inspired the authors of the study to plan and conduct nationwide research; they assessed investment plans for energy storage and heat pumps by potential individual investors, i.e., owners of single-family houses. Based on the results obtained, the authors of the article concluded that the new version of the "My Electricity" program will almost exclusively affect the energy storage market. This impact will stimulate the development and application of this technology. In the case of the heat pump market, the current demand will remain at the same level. The program will contribute to achieving the assumed goals, especially energy consumption at the place of production and reducing so-called low emissions. The program will not affect the demand for heat pumps. [ABSTRACT FROM AUTHOR]

The publication presents heat and electricity management in the Polish steel industry. The paper is based on actual data on heat and electricity consumption and intensity by processes in the steel industry in Poland in Industry 4.0 conditions. Two steel production processes are used in Poland: EAF Electric Arc Furnace and BOF Basic Oxygen Furnace. The analysis is an analysis of actual data is used to characterise the electricity and heat consumption by processes in the Polish steel industry. The analysis shows that the EAF technology is always more electricity intensive and the BOF technology more heat intensive. On the basis of conducted analysis, it can be concluded that pro-environmental innovations in the steel industry should first aim to reduce the electricity consumption of EAF technology and the heat consumption of BOF. An analysis of data for Poland for the period 2004–2020 shows that both cases occurred. The study shows that the heat consumption of BOF technologies has been steadily decreasing since 2010, and the electricity consumption of EAF technologies has been decreasing throughout the period under review. It can be concluded from this that the Polish steel industry is adapting to pro-environmental requirements and, through the introduction of technological innovations, is moving towards the concept of sustainable steel production according to green steel principles. The decrease in energy intensity (means electricity) of steel produced according to EAF technology is an important issue, as the high energy intensity of EAF processes affects the overall energy intensity of the steel production in Poland. In the future, the use of new innovative technological solutions, including solutions based on Industry 4.0 principles, should help the Polish steel industry to further reduce the level of electricity and heat consumption. The driving force behind the investment is the boom in the steel market. The authors made a short-term forecasts of steel production (2022–2025). The annual forecasts determined and analyses made were used to determine the heat and energy consumption of the Polish steel industry up to 2025. [ABSTRACT FROM AUTHOR]

The article presents the results of the analysis of parameters describing electricity consumption in individual phases of the production cycle on a poultry farm. One full broiler rearing cycle on the farm was analyzed. Electrical parameters were tested during the broiler rearing process using a power quality analyzer with a measurement interval of 1 min. During the tests, the analyzer recorded the active and reactive power, phase and line voltage, power factor, and frequency. On the basis of collected data, original indicators describing electricity consumption per chicken wkA, wkQ, and per unit area wiA, wiQ were determined. The regression curves of active and reactive power consumption in particular stages of the cycle were also determined, and the minimum and maximum values of active and reactive power consumption were determined. The accomplished research can be used in planning electricity demand in energy-self-sufficient areas. The presented original indicators can be used to determine power demand on broiler farms, depending on the planned production volume or size of farm buildings. [ABSTRACT FROM AUTHOR]

The analyses presented in the publication allowed, on the basis of the data collected, development of an econometric model for the Polish steel industry from the point of view of the relationship between heat and energy management in the steel production process. The developed model is the main novelty of the paper. The main objective of the study was to develop an econometric model of Poland's heat and energy economy. The following research questions were raised: Is there an econometric model describing heat consumption (intensity) in the steel industry in Poland in relation to steel production and the energy economy? What are the relations between heat intensity and energy prices and steel production in Poland? How might the current energy crisis affect steel production? In the analysis we used data of energy and heat management in the Polish steel industry. An econometric model was developed of the dependence of heat consumption (Yt) on electricity prices (X1t) and steel production (X2t) in Poland. The authors took advantage of open access to data. Annual volumes of heat consumption in steel production processes in Poland were analysed as a function of the annual volume of steel production and the prices of electricity, which are consumed in technological processes in steel mills. We analyzed data for years 2004–2020. The analyses carried out showed that there is an inversely proportional relationship between electricity prices and the intensity of heat consumption by the steel industry. Research shows that rising energy prices lead to lower steel production. This is a dangerous phenomenon for the steel industry in the context of the current energy crisis caused by the pandemic and war in Ukraine. We think that the significance of our results is connected with the fact that the developed model is a useful analytical tool, as it not only allows the analysis of historical data, but can also be used to predict how steel industry parameters will change in the future under the influence of changes in external factors, such as energy prices. This gives a wide range of analytical possibilities for the use of the model. [ABSTRACT FROM AUTHOR]

The aim of this article is to show the impact of the COVID-19 pandemic on electricity consumption and, consequently, on decisions regarding the installation of photovoltaic panels using the example of a selected local authority in Poland—the Szemud Municipality. The analysis was conducted in 2022 and covered the years 2019–2021. An attempt was made to explore the factors that may have triggered an increase in the use of solar energy in households and identify the determinants of installing photovoltaic panels in the period under analysis. Previous analyses of the PV market (and the impact of the pandemic on it) have so far focused on the market as a whole, either in macro or global terms, while studies on smaller municipalities have been limited to examining changes in electricity consumption levels during the COVID-19 pandemic and during lockdown. Therefore, a research gap was identified in that there are no studies analyzing the reasons for the shift from conventional to PV-assisted energy in households, with the COVID-19 pandemic as the background of these changes. The literature research showed that there are currently no studies attempting to establish a link between the increased interest in this type of energy by local authorities and the COVID-19 pandemic. The research confirmed the hypothesis of increased interest in household PV during the pandemic. The main conclusions of the study boil down to the need for further support as well as promotion of the use of solar energy. In addition, the results derived from the empirical research indicate the need to take action at a policy level to counter adverse trends regarding undesirable social behavior. [ABSTRACT FROM AUTHOR]

In Poland, electricity production is based on nonrenewable energy sources. The energy market is dominated by corporations. Rising electricity prices and threats of power shortages have become, among others, prerequisites for the development of distributed sources based on renewable sources, primarily using photovoltaic panels. The development of the renewable energy market is slow due to the lack of legal solutions and insufficient state support. Polish farmers, especially fruit growers, whose electricity consumption costs are a significant item in production costs, may become part of the energy sector by building a local energy system. In 2022, Poland introduced two new legal regulations, which currently provide three options for obtaining electricity using renewable micro-installations. The conducted study aimed at indicating which of the legally permitted option is the most advantageous for fruit farms in Poland. Growers can produce energy by being a prosumer who settles accounts in the net-metering and net-billing system and by participating in an energy cooperative. The direction of changes was ascertained by conducting a pilot study among fruit growers. The study used real quantitative and valuable data on the consumption and costs of electricity in 2012–2022 and the production of photovoltaic panels in a fruit farm in 2021. The study consisted of comparing three models of settling accounts for electricity with two comparative models in two scenarios. The analysis of prosumers' functioning showed that the situation in Poland is favorable for the development of civic energy. However, participation in an energy cooperative with new legal solutions will not always be the more advantageous solution in terms of economy and energy. In particular, the study showed that the support mechanism needs further changes. The results of the research confirm the existing potential of fruit farms, which can be developed in the area of securing energy needs. The results of this research can be used as the premise for introducing changes to the legal conditions for the establishment and operation of energy cooperatives in Poland. [ABSTRACT FROM AUTHOR]

The article presents the global characteristics of the Polish manufacturing industry and the structure of its energy consumption and carbon dioxide emissions related to direct emission as a result of fuel combustion and indirect emission as a result of electricity consumption. The share of individual sectors in energy consumption and emission levels was determined, and the changes in this share over the last 20 years were determined. A method for determining the carbon productivity index for the emissions of individual industries with the use of global macroeconomic indicators was proposed. The index allows for the comparison of the productivity of individual industries, regardless of the nature of production. The change in carbon productivity in Polish industry over time was presented. On this basis, it was assessed which industries are particularly promising in terms of decarbonising the Polish industry. [ABSTRACT FROM AUTHOR]

Determining the demand for heat power for domestic hot water preparation is necessary to perform a building energy assessment. For this, we need to predict domestic hot water consumption. Considering the number of factors influencing domestic hot water consumption, it is difficult to develop a highly accurate methodology. The aim of the study was to compare the real domestic hot water consumption and heat power for its preparation with the values calculated based on the available prediction methods in multi-family buildings. The analysis was carried out based on annual monitoring (2021 year) of domestic hot water consumption and the actual demand for heat power in eight multi-family buildings located in Grudziądz, in Central Poland. The results of these measurements were compared with the values determined based on the available methodologies for forecasting the demand for heat power and domestic hot water consumption: Sander's, Recknagel's, the standard method and the method according to Polish regulations from 2008 and 2015. The real average demand for heat power for domestic hot water was 89.8 ± 8.5 W/person, 211.2 ± 13.7 W/apartment and 4.8 ± 0.3 W/m2, and the daily domestic hot water consumption was 26.7 ± 3.6 dm3/person·day, 62.6 ± 5.8 dm3/apartment·day and 1.4 ± 0.1 dm3/m2·day. The real demand for heat power for domestic hot water was lower than that determined by the analyzed methods. The values obtained from the modified standard method based on Standard PN-92/B-01706/A1: 1999, with mean relative error of 10.5 ± 4.1%, were the closest to the real values. The current ordinance method (Regulation 2015) is characterized by an error of 45.4 ± 10.2%. The predicted domestic hot water consumption using the current ordinance was the closest to the real consumption. On average, it was higher by 7.7 ± 5.0%. [ABSTRACT FROM AUTHOR]

Copyright of Przegląd Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper presents a dedicated system for de-icing trolley wires. The proposed issue is appropriately under the protection of intellectual property for solving as described in patent no.B1 230665 PL in the Patent Office of the Republic of Poland. In the solution presented herein, de-icing is achieved mainly by electrodynamic force excitation and secondarily as a result of heating. Because ice is removed primarily through vibrations, it avoids a large consumption of electricity associated with the high specific heat of water. More importantly, operation is nearly simultaneously applied to the total distance of the trolley power grid between two substations. For this reason, it requires less electricity consumption and less time to apply than in heating, mechanical, or chemical methods. [ABSTRACT FROM AUTHOR]

The ongoing transformation of the Polish power sector have been shaped by a number of factors. In this article, both external conditions for the Polish energy market—such as the country's membership in the European Union—and internal ones—including domestic energy resources and demand for electricity, or the structure of the Polish economy—have been analysed. This study focuses specifically on the issue of development of clean generation technologies as these are fundamental to the energy-transition process. Its determinants have been examined empirically. To this end, econometric models have been developed using sectoral data from the Polish electric power industry. Improvements in technology have been measured as innovation inputs, that is, RD&D investments in environmental technologies. Explanatory variables encompass economic as well as institutional measures: energy price, environmental policy stringency, long-term interest rate, market concentration and protection of intellectual property rights. The findings obtained point to a positive impact of the variables named on the innovative activity in Poland, with the exception of market concentration, which was proven to be statistically insignificant. [ABSTRACT FROM AUTHOR]

The capacity limitations of distribution networks, the increasing demands for electricity installation in terms of electricity quality parameters, and the development of electromobility all increase the need to implement systems in order to stabilize and regulate loads for end users. Battery Energy Storage Systems (BESSs), that operate in internal microgrids of enterprises, allow smoothing of electrical power consumption profiles by actively reducing peak demand power. By using BESSs to implement a peak shaving strategy to reduce the peak power consumption of a company in an external network, energy efficiency can be improved by reducing contractual capacity. The aim of this study is to determine the conditions for the use of energy storage, in order to implement a peak shaving strategy for which the installation of the enterprise microgrid is economically efficient. The analysis of the operating conditions of the BESS should take into account the size of the energy storage, the characteristics of the demand profile for the demand systems, the charges related to electricity, and the costs of electricity storage. In the study, the size of the energy storage was related to the power and electrical capacity of the BESS that was used to implement the peak shaving strategy. The article presents the results of research on the method for determining an effective capacity and power of BESSs for enterprise microgrid systems. The technical and cost limitations of the actual microgrid system, which affected the decrease in economic efficiency of the peak shaving strategy in the company research, were taken into account. The simulations of the operation of the electricity storage system, based on real data of the demand of production companies, were based on the rules and market conditions in Poland. [ABSTRACT FROM AUTHOR]

In Poland, in 2021, an increase in demand for electricity was recorded, and hard coal and lignite power plants still had a dominant share in its production. Another source of electricity was renewable energy sources (RES), mainly wind farms. Young people in Poland are aware that electricity is not only its production, but also consumption in households. Therefore, it is also essential to properly educate young people, aiming at a cost-effective, sustainable lifestyle, in relation to electricity consumption. The article presents the current state of the electricity generation sector in Poland along with the proposed changes in this respect, in particular in terms of the development prospects for the use of renewable energy sources and the influence of government administration on the production and consumption of electricity. The aim of this research was to broaden the knowledge of young people's opinions on energy production and consumption. The research results can be used to create long-term directions of energy policy and to build a social attitude of sustainable energy consumption in Poland. The research was non-probabilistic, based on questionnaires, using the CAWI (Computer Assisted Web Interview) technique. The questionnaire was conducted in 2021, and the analysis was made on the basis of 741 correctly completed research questionnaires. The results of the research confirmed the research hypotheses—that the surveyed youth see the need to reduce consumption as a way to counteract climate change and excessive energy consumption. They also expect government support in the energy transformation in Poland, based on a diversified scenario, using both renewable energy sources (RES) and nuclear energy. [ABSTRACT FROM AUTHOR]

This paper analyzes the changes in carbon dioxide (CO2) emissions related to energy consumption in the Polish agricultural sector between 2000 and 2019. Based on the Logarithmic Mean Divisia Index (LMDI), the changes in agricultural CO2 emissions are viewed in the context of changes in six factors, i.e., CO2 emission intensity, substitution of fossil fuels, penetration of renewable energies, energy intensity, labor productivity and number of employees. The analysis demonstrated that total energy consumption declined over the study period; this was related to a reduction in the intake of energy derived from solid fossil fuels (−1.05%), crude oil (−1.01%), electricity (−4.89%), and heat (−1.37%), and to an increased consumption of natural gas (5.78%) and biofuels (0.82%). Furthermore, it follows from the analysis that changes in CO2 emissions witnessed in that period were consistent with changes in energy consumption levels; this resulted from a negligible transformation of the energy mix (largely determined by fossil fuels). Generally, CO2 emissions declined over the study period at a rate comparable (−0.9%) to that of the reduction in energy consumption (−1.03%). In light of the LMDI method, the reduction in CO2 emissions from fuel consumption in the Polish agricultural sector was mainly driven by a reduction in energy intensity and in employment. Conversely, rapid growth in labor productivity was the key factor in increasing carbon dioxide emissions. Compared to these impacts, changes in other factors (i.e., emission intensity, energy mix and penetration of renewable energies) had an extremely small or marginal effect on the variation in CO2 emissions. [ABSTRACT FROM AUTHOR]

Energy transition forcing a change in the structure of the electricity generation system is a particularly difficult task in countries such as Poland, where the dominant source of energy is fossil fuels. Due to the nature of renewable sources (stochastic and seasonally variable), it is necessary to study their impact on the power system. Much research was conducted on this subject. They consider modelling power systems in terms of dealing with an increasing amount of renewable energy sources, stabilization of electricity generation or environmental aspects. This article examines one of the key sources of future power systems—offshore wind turbines (OWT). The influence of offshore wind sources on the power system in the fields of stability of generation, methods of regulatory strategies, and economics were examined. One of the aspects that are less considered is the correlation of energy production in OWT with energy demand and with generation in other renewable energy sources, especially in the region of the southern Baltic Sea and the distribution of energy demand in countries such as Poland. The key aspect of the research is to fill this gap. The obtained results indicate that the average monthly power generation in OWT is strongly positively correlated with the demand, and the hourly average is positively correlated moderately. Correlation between generation in OWT and photovoltaic sources is very high negative, and between onshore and offshore wind turbines is highly positive. The study indicates that the OWT has a significant potential for the development and replacement of conventional sources, due to the very high capacity and a positive correlation with demand. Moreover, future offshore wind farms can cooperate with photovoltaic sources as these sources complement each other. On the other hand, a significant saturation of the system with offshore and onshore wind sources may pose a threat to the power system due to their positive correlation. [ABSTRACT FROM AUTHOR]

A hybrid air conditioning system, which is composed of a novel gravity-assisted heat pipe (GAHP)-based indirect evaporative cooler (IEC) and direct expansion (DX) cooling coil, is proposed and investigated here. After developing a mathematical model to describe the performance of the GAHP-based IEC, the hybrid system is evaluated during the cooling design day for providing thermal comfort for an office building in Poland. The results are obtained and compared with the combination of a rotary heat exchanger (RHE) and DX cooling coil as the conventional hybrid system. The comparison is performed by analyzing cooling capacity, electricity consumption, and coefficient of performance profiles, which describe the technical, energy, and efficiency aspects, respectively. The results show that the GAHP-based IEC hybrid system is able to enhance the energy performance significantly compared to the conventional one. The proposed hybrid HVAC system improves COP by 39.2% and reduces electricity consumption by 45.0%, according to the design-day of 24 August and the outdoor temperature of 30 °C. As a result, the total operating cost for the assumed cooling season is reduced by 51.7%. [ABSTRACT FROM AUTHOR]

An important question in the literature on climate change and sustainable development is the relationship between countries' economic growth, household electricity consumption and greenhouse gas emissions. Despite the ongoing COVID-19 pandemic and related economic restrictions, sustainable economic growth remains at the forefront of the global development agenda. However, given the strong relationship between the ever increasing electricity consumption and greenhouse gas CO2 emissions, an increasing number of scientists have been questioning the feasibility of the planned emission reduction. In my research, I strove to determine whether there exists a relationship between the change in the structure of electricity consumption of households in selected EU Member States (15 countries), the impact of innovation, changes in electricity prices and economic growth, and CO2 emissions in 2007–2019, prior to the outbreak of the COVID-19 pandemic, and following its third wave (2021). The aim of the article is to propose a synthetic index to assess the degree of sustainable energy development (SISED) in selected EU countries. Multiobjective decision analysis (MODA) was applied in order to assess the sustainable energy development of the selected European countries. Research findings may contribute to both literature and practice if they are applied by individual EU countries in the process of formulating directions aimed at achieving sustainable energy development. [ABSTRACT FROM AUTHOR]

LED lamps, which are becoming prevalent in horticulture, are also being installed in greenhouses dedicated to cereal crop breeding. However, the issue arises with the real efficiency of LED lamps. Besides high-budget programs, the smaller breeding companies in Poland face problems concerning the plant growth under LED lamps and the real costs of their exploitation. The experiment was conducted to compare seven different LED lamps and a high-intensity discharge (HID) lamp with a high-pressure sodium lamp (HPS) used as a control. For studies, two varieties of wheat, barley, and oat species were used. The plants' growth rate was assessed based on elongation growth and earing time. Plants' physiological conditions were evaluated using chlorophyll a (Chl a) fluorescence measured on dark-adapted leaves. The light spectra and intensities of tested lamps in parallel with electricity consumption were also recorded. The results showed that 1) LEDs' physical properties and luminaire construction influence the amount of electricity consumed; 2) the cereal crop species differ in lighting requirements. The less light-sensitive was oat opposite barley, with wheat of moderate sensitivity; 3) LED-6 lamp (PlantaLux S.A, Lublin, Poland) based on white diodes enriched by blue ones was the most cost-efficient and most optimal for studied species. [ABSTRACT FROM AUTHOR]

The article discusses the research on CO2 emissions at the stage of electric engine vehicle operation. The operation stage includes, among others use of the vehicle as well as maintenance and charging for the vehicle's propulsion. The origin of the electricity consumed during charging has an impact on the vehicle's emissions balance. The scope of considerations concerns coal as the main energy carrier in Poland. The obtained results can be a benchmark for comparing other primary energy sources used for electricity production. Based on the collected technical data of electric cars, the values of CO2 emission factors from electricity production in thermal power plants and data on the state and structure of electricity production in Poland, an analysis of CO2 emissions from electric vehicles in the operational stage was performed. The vehicle's electricity consumption of 0.14-0.16 kWh/km is accompanied by CO2 emissions of 100.94-115.36 g/km. The calculated CO2 exceeds the EU limit value from 01/01/2020 (95 g/km) for average CO2 emissions from new passenger vehicles. The main message of the work is the statement that increasing the efficiency of the electricity generation process in commercial thermal power plants in Poland will translate into a reduction in the emission of electric cars consuming this energy for propulsion. The research shows that the change in the efficiency of energy transformations in a thermal power plant from 38% to 46% leads to a reduction in the emission of an electric vehicle by over 17%. The emission of CO2 from a passenger car with a compression-ignition engine is discussed. The considerations include the stage of the use of the vehicle and the stage of production of diesel oil, which is consumed during the use of the vehicle. [ABSTRACT FROM AUTHOR]

It is necessary in agricultural consulting to take into account the current problems as well as economic and social challenges facing rural areas. Undoubtedly, sustainable economy and energy policy is such a problem in Poland, including the issue of access to energy from renewable sources and financial possibilities of meeting the electricity demand of households and agriculture. Therefore, advisory and information activities in the field of reducing energy poverty and improving air quality are important. The main purpose of the paper was to identify and assess the role of advisory entities in the process of counteracting energy poverty in rural areas in Poland. The basic research method was an expert (survey) study. Research shows that the subject of energy poverty is relatively rarely taken up by consulting institutions as part of training courses, especially issues related to saving electricity in the household/agricultural sector are marginalized; monitoring and analysis of energy consumption; selection of technical devices in terms of energy efficiency. Based on expert research, there were identified consultancy activities that are and may be important in the topic under study. Experts indicated co-financing of activities in the field of energy efficiency as the preferred way to fight energy poverty in agriculture and rural areas. The results may constitute an important direction in the development of consultancy, the basis for building priority programs, which in turn may affect the behaviour and actions of farmers and other inhabitants of rural areas in the context of energy transformation. The performed research may constitute the basis for further, in-depth analyses in other countries and on an international scale. [ABSTRACT FROM AUTHOR]

Motivation: The studies on sustainable consumption are conducted in Poland and worldwide on the basis of various source data. Macroeconomic perspective is one of research approaches. The data obtained from the system of national accounts are especially important for the assessment of the situation in Poland. As a result of research specific indicators are obtained which express changes in various areas of functioning of consumption entities in the perspective of sustainable consumption. Aim: to indicate the main trends of research on sustainable consumption in macroeconomic approach in Poland and to recognise the changes in the area of sustainable consumption on the basis of indicators adopted in the research on sustainable development conducted by Central Statistical Office. Results: In Polish official statistics, the process of tracing sustainable development which includes sustainable consumption as an integral part, can be conducted with the use of the set of indicators monitoring four main orders, i.e. social, economic, environmental and institutional, as well as political order. Indicators related to the patterns of sustainable consumption are located in the group of indicators of social order and include such measures as the structure of average monthly expenditure per capita in households by type, the structure of passenger cars by age groups and electricity consumption in households per capita. Conducted research shows that in the years 2004-2019 favourable changes were reported in Poland in the structure of individual consumption in the household sector. They were related to the decrease in the value of the food index and the increase in the expenditures free choice indicator. At the same time, the data from Central Statistical Office shows that a regression was observed in the other two research areas, i.e. the structure of passenger cars by age and energy consumption in households. [ABSTRACT FROM AUTHOR]

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Lignite still plays a key role in the production of electricity in Poland. About one-third of domestic electric energy comes from lignite burned in large power plants that produce megatons (Mt) of bottom ash and fly ash annually. Nearly 11 wt% of the total ash generated by the lignite-fired power industry in Poland comes from lignite extracted from the Konin Lignite Mine. Part of the ash escapes into the atmosphere, and the rest is utilized, which is expensive and often harmful to the environment; hence, geochemical studies of these ashes are fully justified and increasingly carried out. The lignite samples examined in this paper represent the entire vertical section of the first Mid-Polish lignite seam (MPLS-1) mined in opencasts at Jóźwin IIB, Drzewce, and Tomisławice. First, the samples were oxidized (burnt) at one of three temperatures: 100, 850, and 950°C; then the chemical composition of oxides and trace elements was determined according to the ASTM D6349-13 standard. The ashes were rich in SiO2 and CaO; Ba, Sr, and Cu dominated the trace element content. Among the harmful elements found, Pb is of most concern. Only a few elements (Ba, Cu, Pb, Sb) reached values higher than their corresponding Clarke values. Based on the results obtained, it can be concluded that the examined ashes are approximately as harmful to the environment as ashes from other lignite used to generate electricity. Moreover, the increased amount of CaCO3 in the MPLS-1 is beneficial in the process of natural desulphurization. [ABSTRACT FROM AUTHOR]

The impact of environmental regulations introduced by the European Union is of key importance for electricity generation systems. The Polish fuel structure of electricity production is based on solid fuels. Moreover, the generating base is outdated and must gradually be withdrawn from the power system. In this context, Poland's energy policy is undergoing a transformation as climate and environmental regulations are becoming increasingly stringent for the energy sector based on solid fuels (hard coal and lignite). However, the transformation process must be adapted to market demands, because the overriding goal is to ensure energy security by maintaining the continuity of energy supplies and an acceptable electricity price. This directly contributes to the development of the entire economy and the standard of living of the society, in accordance with the European Agreement establishing an association between the Republic of Poland and the European Communities and their Member States, signed on 16 December 1991, and the European Energy Charter, signed on 17 December 1991. Ensuring energy security is the most important goal of the energy policy. Therefore, energy companies must forecast the demand. The main goal of this article is to develop a mathematical model of electricity consumption by 2040 by all sectors of the economy: industry, transport, residential, commercial and public services, agriculture, forestry, and fishing. In order to achieve the intended goal, a model was developed by using Long Short-Term Memory (LSTM) artificial neural networks, which belong to deep learning techniques and reflect long-term relationships in time series for a small set of statistical data. The results show that the proposed model can significantly improve the accuracy of forecasts (1–3% of mean absolute percentage error (MAPE) for the analyzed sectors of the economy). [ABSTRACT FROM AUTHOR]

Salt formations of an appropriate thickness and structure, common over the globe, are potential sites for leaching underground caverns in them for storage of various substances, including hydrogen. Underground hydrogen storage, considered as underground energy storage, requires, in first order, an assessment of the potential for underground storage of this gas at various scales: region, country, specific place. The article presents the results of the assessment of the underground hydrogen storage potential for a sample bedded salt formation in SW Poland. Geological structural and thickness maps provided the basis for the development of hydrogen storage capacity maps and maps of energy value and heating value. A detailed assessment of the hydrogen storage capacity was presented for the selected area, for a single cavern and for the cavern field; a map of the energy value of stored hydrogen has also been presented. The hydrogen storage potential of the salt caverns was related to the demand for electricity and heat. The results show the huge potential for hydrogen storage in salt caverns. • The assessment of hydrogen storage capacity for a salt cavern is presented. • Salt deposits have huge potential for hydrogen storage. • Maps of hydrogen storage capacity demonstrate potential for using salt formation. • Hydrogen storage capacity maps provide important data for various branches of industry. [ABSTRACT FROM AUTHOR]

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• A mechanical biological treatment plant is examined in Poland. • Mass losses in the biological treatment process for MBT systems. • The average electricity demand for MBT systems. • The efficiency of waste recovery in MBT systems. In the professional literature there is no information on the efficiency of waste treatment in MBT (mechanical-biological waste treatment) systems in Poland. This knowledge is currently particularly important as it will decide on the role of the MBT system in the new reality of the circular economy, and consequently on the direction and necessary scope of modernization of these systems. The article presents a series of technical and technological indicators designated for one of the recently commissioned MBT plants against the background of minimum, maximum and average values of these parameters set for 20 systems with various MBTs covered by the research as part of the review of technological solutions used in Poland, made in 2015. For the system in Marszów, respectively in 2017 and 2018, the average value of the ratio of underscreen to overscreen fraction was 1.4; the losses of mass in the biological treatment process amounted to 28.7 and 29.4%; energy demand – 46.6 and 44.3 kWh/Mg; the aeration index – 16.7 m3/(Mg h); the average waste recycling rate – 15.2 and 17.3%; the share of fuel fraction recovery – 11.6 and 16,6% and the share of waste sent to landfill – 33.2 and 32.3%. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to model electricity consumption using Artificial Neural Networks (ANN). Total electricity consumption and consumption generated by households (HH) were modeled. The input variables of the ANN were based on nighttime light images from VIIRS DNB. Studies conducted thus far have covered mainly linear models. Most of case studies focused on single countries or groups of countries with only few focusing on the sub-national scale. This paper is pioneering in covering an area of Poland (Central Europe) at NUTS-2 level. The use of ANN enabled the modeling of the non-linear relations associated with the complex structure of electricity demand. Satellite data were collected for the period 2013–2016, and included images with improved quality (inter alia higher resolution), compared to the DMSP/OLS program. As images are available from April 2012 onwards, it is only recently that their number has become sufficient for ANN learning. The images were used to create models of multilayer perceptrons. The results achieved by ANN were compared with the results obtained using linear regressions. Studies have confirmed that electricity consumption can be determined with higher precision by the ANN method. • Innovative modeling of electricity consumption by artificial neural networks based on nighttime light images from VIIRS DNB. • A new way of preparing the input data of the model. • Total electricity consumption and electricity consumed by households were modeled. • The first electricity consumption analysis covered regions of Poland (Central Europe) at NUTS-2 level. [ABSTRACT FROM AUTHOR]

This work gives an overview on how the projected changes in the extremes in Poland might impact human health and economy. For that purpose, statistically corrected data from 7 regional climate models were used. A significant increase of extreme hot events (i.e. heat waves, tropical nights) is projected for Central and Southern Poland for the end of the 21st century which might seriously affect a society living in large urban areas. Less extreme cold events improve thermal comfort in winter. The negative impact of the warming will affect energy systems with higher demand for electricity in summer and agriculture: an earlier beginning of the growing season and flower blooming will enhance the risk of frost damages in spring, whereas excessive heat will reduce yields in summer. Polish tourism should benefit from higher thermal comfort (except for hot July and August in the far future and warming in the winter season bringing snow cover depletion in the near future). [ABSTRACT FROM AUTHOR]

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Among micro-cogeneration (μCHP) systems, an interesting solution is one based on the Stirling engine, which is the main object of interest of this paper. First, a numerical model of the engine was built based on Schmidt analysis. The model indicated the possible range of improvements resulting in increased efficiency or increased power. Next, the potential for the use of a μCHP system based on the Stirling engine was evaluated. Data from real-time, long-term measurements in a building located in Poland were taken as the input values for the analysis. The results show that the considered solution can meet the electricity and heat demands of single-family houses throughout the year; however, heat storage system is required to optimize the operation of the device and extend the operation of the system to produce electricity. Depending on the local mechanisms, electricity storage may also be needed. The environmental effect of the considered system is positive, provided that renewable energy sources do not constitute an alternate solution. The application of μCHP in buildings also decreases the exploitation cost, which depends mainly on the heat and electricity demand, price of electricity purchased and sold to the grid, price of natural gas and existing support mechanisms. [ABSTRACT FROM AUTHOR]

[Display omitted] • We investigate Multi-Criteria Decision Analysis (MCDA) methods application in the renewable energy sources (RES) evaluation domain. • We propose a new MCDA method called CODAS-COMET. • We assess Green Electricity Generation in Poland using the method developed. The purpose of this paper is to present the new hybrid multi-criteria decision analysis (MCDA) method CODAS-COMET for evaluating sustainable electricity generation considering renewable energy sources (RES). The introduced approach combines the advantages of two known MCDA methods: Characteristic Object METhod (COMET) and COmbinative Distance-based ASsessment (CODAS). Due to the advantages of the COMET method, the proposed approach enables the identification of the whole domain model, is resistant to the rank reversal phenomenon, is easy to apply, and allows to obtain an objective and reliable recommendation based on the gathered data. Meanwhile, combining the COMET method with CODAS eliminates the limitations of COMET by automatizing and accelerating the characteristic object comparison procedure. The presented method's practical application includes evaluating Poland's sixteen voivodeships, considering the sustainable use of RES in the electricity generation domain. An additional contribution of this research is to investigate the impact on results of distance metrics other than the default distance metric used by the method that is the focus of this paper and demonstrate the design and practical application of a research framework for selecting the most appropriate metrics. A comparative analysis of the CODAS-COMET method with the TOPSIS-COMET reference approach was performed to confirm the results' reliability. The results showed a high correlation among all final rankings and confirmed the robustness of the CODAS-COMET approach to changing metrics in the algorithm. Furthermore, the results proved that our approach is a suitable and valuable tool for sustainability assessment in renewable energy domains and other complex issues requiring consideration of multiple criteria. [ABSTRACT FROM AUTHOR]

Research on the photovoltaic module efficiency in the south of Poland was conducted in 2009 in Stryszawa and afterwards in 2012 in Zabrze and Stryszawa. The research involved taking measurements of electric energy produced by systems of various power and technical solutions. The efficiency of PV modules was compared to the intensity of solar radiation in the locations under consideration and, thus, the efficiency of converting solar energy into electricity was determined. The research results facilitated designing and mounting of forty PV microsystems in Zabrze in 2014 (power from 2000 Wp to 3000 Wp). To the satisfaction of their users, they operate without failure. [ABSTRACT FROM AUTHOR]