This paper explores relationships among CSR practices in the social, economic and environmental dimensions and digitization in the Polish energy companies. The study used the CATI method, and the data obtained from 110 companies was analyzed using a set of methods starting with correlation analysis, through regression analysis, including backward stepwise regression. Obtained results led to the formulation of SEM (Structural Equitation Modelling) model that has been tested. Results confirm the influence of social CSR practices on practices in economics and environmental CSR dimensions and on the level of digitalization. Research also suggests that there is essentially no significant impact of the size of the enterprise on the level of digitalization, as well as on any of the analyzed types of CSR practices.

The COVID-19 pandemic has generated multiple impacts. In particular, in the educational sector, the virtual class modality generated changes in the patterns of energy consumption at the institutional level; the identification of this consumption will allow us to reflect on new energy saving and efficient use strategies. In this research, we present a case study of the effects of the COVID-19 pandemic on electricity consumption in 13 state universities in Michoacán, Mexico. Electric energy consumption has been evaluated before and during the presence of the COVID-19 between 2019 and 2020. The comparative analysis estimated the reduction in energy consumption and its economic and environmental impact. The results show a considerable decrease in electricity consumption, generating an average saving of 76.24 MWh/month, which translates into an annual emission reduction from 2019 to 2020 of approximately 497 TnCO2e, and in economic terms of $8,882.25 USD each month. In general, it was ident... [more]

Construction of offshore gas wells is characterized by increased requirements for both the technological process in general and the technological parameters of drilling fluids in particular. Parameters and properties of the used drilling muds must meet a large number of requirements. The main one is the preservation of the permeability of the reservoirs, in addition to the environmental and technological concerns. At the same time, pressures in the productive formation at offshore fields are often high; the anomaly coefficient is 1.2 and higher. The use of barite in such conditions can lead to contamination of the formation and a decrease in future well flow rates. In this regard, the development and study of the compositions for weighted drilling muds is necessary and relevant. The paper presents investigations on the development of such a composition based on salts of formic acid (formates) and evaluates the effect of the molecular weight of the polymer reagent (partially hydrolyzed... [more]

Supercritical carbon dioxide (SCO2) jets are a promising method to assist drilling, enhance oil−gas production, and reduce greenhouse gas emissions. To further improve the drilling efficiency of SCO2 jet-assisted drilling, organ-pipe nozzles were applied to generate a self-excited oscillation SCO2 jet (SEOSJ). The impact pressure oscillation and rock erosion capability of SEOSJs under both supercritical and gaseous CO2 (GCO2) ambient conditions were experimentally investigated. It was found that the impact pressure oscillation characteristics of SEOSJs produced by organ-pipe nozzles are dramatically affected by the oscillation chamber length. The optimum range of the dimensionless chamber length to generate the highest impact pressure peak and the strongest pressure oscillation is within 7−9. The dimensionless pressure peak and the pressure ratio decreases gradually with increasing pressure difference, whereas the pressure oscillation intensity increases with increasing pressure differ... [more]

To use lithium-iron-phosphate battery packs in the supply systems of any electric mining equipment and/or machines, the required conditions of work safety must be met. This applies in particular to coal mines endangered by fire and/or explosion. To meet the spark-safety conditions, the cells (together with the battery management system—BMS) must be isolated from the influence of the environment, and therefore placed in special fire-tight housings. This significantly degrades the heat dissipation, thus affecting the operating conditions of the cell-packs. Therefore, their usage without the so-called BMS is not recommended, as shown in the authors’ preliminary research. In practice, various BMS are used, most often with the so-called passive balancing. However, their application in mines is uncertain, due to the effect of heating under operation. When it comes to active BMS, they usually possess a quite complex structure and hence, are relatively expensive. Therefore, the authors conduct... [more]

Meeting the Paris Agreement on climate change requires substantial investments in low-emissions energy and significant improvements in end-use energy efficiency. These measures can also deliver improved air quality and there is broad recognition of the health benefits of decarbonising energy. Monetising these health benefits is an important part of a robust assessment of the costs and benefits of renewable energy and energy efficiency programs (clean energy programs (CEP)) and a variety of methods have been used to estimate health benefits at national, regional, continental and global scales. Approaches, such as unit damage cost estimates and impact pathways, differ in complexity and spatial coverage and can deliver different estimates for air pollution costs/benefits. To date, the monetised health benefits of CEP in Australia have applied international and global estimates that can range from 2−229USD/tCO2 (USD 2016). Here, we calculate the current health damage costs of coal-fired po... [more]

The global energy mix is shifting from fossil fuels to combinations of multiple energy storage and generation types. Hybrid energy system advancements provide opportunities for developing and deploying innovative green technology solutions that can further reduce emissions and achieve net-zero emissions by 2050. This study examined the impact of an increasing share of wind and solar electricity production on reducing carbon intensity by controlling coal and lignite domestic consumption and the production of refined oil products in a world aggregated data panel. Data covering the last three decades were used for the analysis by the ARDL bounds testing approach. The results showed that an increasing share of wind and solar electricity production would be helpful to decrease carbon intensity in the short and long term. On the other hand, a 1% increase in coal and domestic lignite consumption increased carbon intensity by 0.343% in the short run and 0.174% in the long run. The production o... [more]

Carbon storage in soil increases along with remediation of post-mining soils. Despite many studies on the issue of carbon sequestration in soils, there is a knowledge gap in the potential and mechanisms of C sequestration in post-mining areas. This research, including nuclear magnetic resonance analysis, determines the soil organic carbon formation progress in a long-term study of limestone (S1), and lignite (S2) post-mining soil under different remediation stages. The main remediation target is reforesting; however, S2 was previously amended with sewage sludge. The study showed that for S1, the O-alkyl groups were the dominant fraction in sequestered soil. However, for S2, increased fractions of acetyl-C and aromatic C groups within remediation progress were observed. The remediation of S1 resulted in improved hydrophobicity and humification; however, the decrease in aromatic groups’ formation and C/N ratio was noted. For S2, we noticed an increase for all indicators for sequestered C... [more]

All the urban areas of developed countries have hydric distribution grids and sewage systems for collecting municipal wastewater to treatment plants. In this way, the municipal wastewater is purified from human excreta and other minor contaminants while producing excess sludges and purified water. In arid and semi-arid areas of the world, the purified water can be used, before discharging, to enhance the energy efficiency of seawater desalination and solve the problems of marine pollution created by desalination plants. Over the past half-century, seawater desalination has gradually met demand in urbanized, oil-rich, arid areas. At the same time, technological evolution has made it possible to significantly increase the energy efficiency of the plants and reduce the unit cost of the produced water. However, for some years, these trends have flattened out. The purified water passes through the hybridized desalination plant and produces renewable osmotic energy before the final discharge... [more]

Psychological adaptation to ambient temperatures is fascinating and critical, both theoretically and practically, for energy efficiency in temperate climates. In this study, we investigated and compared the brain response (event-related potentials with a late positive component and latency ~300 milliseconds; labeled “P300” in the present study) and reaction times of Indonesian participants (n = 11), as tropical natives living in Japan, and Japanese participants (n = 9) in natural (i.e., hot during the summer and cold during the winter) and comfort conditions (with cooling and heating). Thermal comfort under contrasting conditions was studied using both instruments and subjective ratings. P300 potential and reaction time were measured before and after a Uchida−Kraepelin (U−K) test (30 summation lines). The results showed that P300 potential and latency did not change between the pre- and post-U−K test among conditions in any of the groups. Furthermore, Indonesian participants showed low... [more]

Citizens are beginning to play a key role in the development of the smart city concept, providing a wealth of information for the sustainable development of cities. For this research, we planned and conducted empirical studies to examine the areas influencing the quality of life from the point of view of municipalities. A questionnaire form was developed and a survey was conducted on a sample of 84 municipal offices in Poland. We tabulated, statistically processed and analysed the results and thoroughly investigated the areas influencing the quality of life, their impact and importance. We determined which areas of the city are included in municipal research and checked whether there was a need to expand these areas. We found that the people responsible for research in municipal offices are aware that the quality of life is influenced by many areas and conditions. However, these people only choose selected areas for research and have a problem with indicating what can be extended to th... [more]

Small Island Developing States (SIDSs) are faced with challenges such as reducing the share of fossil energy and waste landfilling. This work summarizes the main aspects of 53 SIDSs that constrain economic development, energy sources, and waste management strategies. An integrative bibliographical review is conducted to synthesize the state-of-the-art of waste-to-energy (WtE) strategies and compare the technologies in light of their suitability to SIDS. The findings show that considering the large amount of waste produced annually, WtE technologies are of the utmost importance to reduce ecological footprints (EFs) and greenhouse gas (GHG) emissions, and to increase the share of renewable energy with the installation of incineration plants with energy recovery to replace fossil fuel power plants. Although WtE is recommended for all SIDSs, the Atlantic, Indian Ocean, Mediterranean, and South China Sea (AIMS) countries exhibit higher population density (1509 inhab/km2) and a high share of... [more]

In this study, modern nitrogen steels used for the manufacture of rings for Honda engines (70CC, 90CC, CRF70F, XL70, XR70, C70, CT70, ATC70, CL70) as well as other transport tribotechnical units was investigated. Due to the present ecological situation in the world, new environmentally friendly lubricating fluids for nitrogen steels’ tribotechnical units and surface treatments have been proposed. The results of tribotechnical tests are presented in the form of diagrams, graphs and step polynomials obtained by mathematically describing the changes in wear intensity when the load changes for different lubricating fluids. Friction pairs were compared with ShellHF-E 46 (synthetic lubricating fluid), ShellHF-R (biological origin) and lubricating and cooling liquids with 1%, 3% and 5% vegetable oil concentrations. In tribocoupling it was found that hydrogen diffuses into the metal because the tribodestruction of lubricating coolants plays an active role in the destruction of friction surface... [more]

Energy-saving and efficiency represent a crucial role in achieving a clean environment as well as economic and social development, providing substantial benefits to stakeholders, including householders. Better cost savings can be achieved by simply changing behavior. However, real energy users lack proper technical energy knowledge, awareness, and education in most cases. In most countries, women are involved in a higher percentage of energy activities in household chores but have less gender participation in energy decisions. In this regard, a gender perspective effectively understands energy users’ pragmatic and strategic needs for energy-saving behavior improvement. Previous literature reviews have been focusing on specific aspects of energy sustainability; however, no review has focused on energy-saving from a gender perspective to the best of our knowledge. It aims to provide a systematic review of literature on energy-saving and management, highlighting the importance of gender r... [more]

The poor indoor air quality (IAQ) of severely polluted toilets is associated with increased risk of severe disease. This study aimed to evaluate the overall IAQ according to the contaminant removal efficiency, volume average concentration, and breathing zone control level. The characteristics of contaminant transmission in a non-flushing ecological toilet (NFET) were analyzed using the computational fluid dynamics (CFD) methodology, and the proposed model was further validated based on experimental measurements. Both an orthogonal experimental design and CFD were used to analyze factors such as exhaust fan position (EFP), air change rate per hour (ACH), natural vent location (NVL), and grid height (G-h). The EFP and ACH were demonstrated to be the dominant factors affecting the IAQ, whereas NVL and G-h were found to play key roles. Single-factor analysis based on the significance levels of the ACH, EFP, and NVL was conducted using the CFD methodology to define three exhaust behaviors—n... [more]

Many high speed applications employ a surface permanent magnet (PM) machine topology with a retaining sleeve due to its robustness and ability to achieve high overall peripheral speeds as well as efficiencies. One often overlooked feature in the mechanical design of such machines, which has not achieved sufficient attention to date is the anisotropic thermal expansion of rare earth magnets, the degree of which varies for different magnet technologies. This paper investigates the effects of the aforementioned on the mechanical design of a high speed PM spindle machine with NdFeB magnets. The maximum allowable interference is found to be limited by the working temperature of the magnets while the minimum required interference is increased due to their anisotropic thermal expansion. Based on this, appropriate conditions are formulated to integrate a Neodymium Iron Boron (NdFeB) PM in high speed rotors. These modifications considering the shaft together with the magnet anisotropic thermal... [more]

The environmental performance of a combined cooling, heating, and power system is analyzed in this study at a component-level using a SPECO-based exergoenvironmental analysis. The engine consumes natural gas and produces 168.6 kW net power. The waste heat is recovered by a LiBr-H2O absorption chiller and a heat exchanger, which are used for cooling and heating purposes. The energy system is assisted by a solar field. An environmental Life Cycle Assessment quantifies the environmental impacts of the system, and these data are combined with exergy evaluations. The highest total environmental impact rate, 23,740.16 mPt/h, is related to the internal combustion engine, of which pollutant formation is the primary source of environmental impact. Compared with a non-renewable energy system, the solar-assisted trigeneration system decreased the environmental impact per exergy unit of chilled water by 10.99%. Exergoenvironmental performance can be further improved by enhancing the exergy efficie... [more]

Current EU policy will force a significant reduction of hard coal mines in the near future due to environmental restrictions. There are also numerous non-coal underground mines that will be excavated in the next few years. Taking the above into consideration, it is worth starting to plan further steps in terms of reclamation of these facilities. Within this manuscript, both recently used and novel approaches to underground space reclamation have been reviewed. Selected methods of reclamation were analyzed in terms of their strengths and weaknesses, and the results were compared with the effect of a commonly used approaches (i.e., filling or flooding of underground space after mine termination). The analysis has been performed in the scope of sustainable development. Taking into account the opinion of many stakeholder groups and underground facilities, reuse was considered as an action aimed at fulfilling sustainable development goals and the circular economy concept. Based on numerous... [more]

The study examined the impact of different factors on greenhouse gas (GHG) emissions, by applying the extended STIRPAT model and decoupling analysis for Tunisia for the period 1990−2018. Furthermore, the study utilizes Tapio decoupling model, and the Auto-Regressive Distributed Lag (ARDL) bounds test approach to examine the relationship between the variables of greenhouse gas (GHG) emissions, economic growth, energy consumption, urbanization, innovation, and trade openness. The findings validated an inverted U-shape relationship between GDP and GHG emissions. In addition, we find that the consumption of renewable energy contributes to the reduction of GHG emissions in the long run. The findings call authority for the adaption of the regulatory framework relating to energy management, energy efficiency and the development of renewable energies, as well as to initiate energy market reforms, implement mitigation strategies and encourage investments in clean energies.

The development of the world economy goes hand in hand with increased energy consumption and global warming caused by greenhouse gases. These issues can be tackled by implementing promising technologies of power generation. They differ from the known ones in that new energy resources are involved, e.g., mixtures of various types of biomass, provided that hazardous gas emissions during the production process are minimized. The development of high-potential energy-efficient and environmentally friendly technologies which use biofuel in the energy industry requires scientific evidence for the mechanisms, conditions, and characteristics of physical and chemical processes during pyrolysis and gasification of biomass, including its multicomponent types. This article analyzes the world technologies and research findings in the field of biomass pyrolysis and gasification. The effect of a group of factors on the intensity and completeness of gasification and pyrolysis of biofuel compositions ha... [more]

The quality of outdoor air in many places, especially in urbanized areas, is bad; therefore, a series of studies aimed at assessing the impact of outdoor air parameters on indoor air quality was conducted. Four nurseries (three buildings) located in different parts of Poznań, Poland were selected as research sites. During the research period, the concentrations of CO2, PM2.5, and PM10 inside and outside the buildings over time were analyzed. Measurements outside the buildings were supplemented with an analysis of traffic near nurseries and an assessment of pollutant emissions from vehicles of various categories. Measurements were conducted during the COVID-19 pandemic in a weekly series during winter (December)—(W), spring (April)—(S), and at the end of spring (June)—(LS). Testing and analyses indicated poor indoor air quality in three out of four nurseries. To ensure indoor air quality at the proper level, it is necessary to supply rooms with outside air. Ventilating rooms by airing,... [more]

The paper places emphasis on primary energy resources, their covariation, and their correlation with socioeconomic factors and aims to provide a systematic analysis of their development over time. The analysis uses evidence from European Union (EU) country-level data and is based on visual analytics techniques. Different results from the same territories show that energy consumption does not always reflect or is due to climatological or meteorological conditions. Extensive use of visualization is adopted as a means of contributing to the understanding of energy use, some involved problems and concepts, and energy consumption trends over time. We present an approach that addresses the informatics challenges based on the integration of visualization software, data integration, and cluster analysis. Our cross-sectional energy review advocates that EU energy leaders are moving towards a low-carbon economy. The correlations of energy variables with economic and pollution effects are stronge... [more]

The aim of the manuscript was to present the collective results of research on the profitability of using various renewable sources in Poland with the greatest development potential. In the paper, the economic parameters of various investment projects were determined and calculated, i.e., Net Capital Value (NPV), Internal Rate of Return (IRR) and the Period of Return on Invested Capital (PBT). The economic assessment of the use of RES technologies was supplemented with the assessment of environmental benefits. The ecological criterion adopted in the study was the assessment of the potential and costs of reducing greenhouse gas emissions as a result of replacing fossil fuels with renewable energy technologies. On the basis of the constructed economic model to assess the profitability of investments, it has been shown that the analyzed projects will start to bring, depending on their type and technical specification, measurable economic benefits in the form of a reduction in the amount o... [more]

The need for advancements in residential construction and the hazard induced by the shrink−swell reactive soil movement prompted the development of the prefabricated footing system of this study, which was assessed and compared to a conventional waffle raft using a multi-criteria analysis. The assessment evaluates the structural performance, cost efficiency, and sustainability using finite element modelling, life cycle cost analysis, and life cycle assessment, respectively. The structural performance of the developed prefabricated system was found to have reduced the deformation and cracking by approximately 40%. However, the cost, GHG emission, and embodied energy were higher in the prefabricated footing system due to the greater required amount of concrete and steel than that of the waffle raft. The cost difference between the two systems can be reduced to as low as 6% when prefabricated systems were installed in a highly reactive sites with large floor areas. The life cycle assessme... [more]

Achieving zonal isolation along wellbores is essential for upholding the containment integrity of subsurface reservoirs and preventing fluid seepage to the environment. The sealing performance of Portland cements conventionally used to create barriers can be severely compromised by defects like fractures or micro-annuli along casing−cement−rock interfaces. A possible remediation method would be to circulate reactive fluids through compromised cement sections and induce defect clogging via mineral precipitation. We assess the sealing potential of two prospective fluids: sodium bicarbonate and sodium silicate solutions. Reactive flow-through experiments were conducted on 6-m-long cemented steel tubes, bearing ~20-μm-wide micro-annuli, at 50 °C and 0.3−6 MPa fluid pressure. For the sodium bicarbonate solution (90 g/kg-H2O), reactive flow yielded only a minor reduction in permeability, with values remaining within one order. Injection of sodium silicate solution (37.1 wt.%, SiO2:Na2O molar... [more]