The effects of urban transport are highly concerning. The rapid urbanization and motorization in smart cities have a huge impact on sustainability. The goal of the paper is to analyse the smart cities selected, in terms of the urban transport. This paper presents an overview of research works published between 1991 and 2020 concerning urban transport and MCDM (multi-criteria decision making). The author highlights the importance of decision-making criteria and their weight, as well as techniques. Seven criteria and forty-four objects were used as the input of the approach. The entropy weight method was used to compute the weight of each criterion. The TOPSIS (Technique for Order Performance by Similarity to Ideal Solution) was applied to calculate the assessment and ranking of transport performance for each smart city. Portland was found to be the best location for transport enterprises and projects; Tbilisi was ranked last. The values of the relative closeness coefficient ranged from... [more]

The Scheffler type concentrator is a curved metal reflector particularly suitable for solar thermal systems with a receiver fixed to the ground. Its operating principle is to deform the reflector throughout the year to optimize its performance in collecting sunlight. This study analyses the optical performance of a Scheffler reflector during the year. A CAD software tool is utilized to reproduce the mechanical deformations of a real Scheffler concentrator and the shape of the light spot on the receiver is analyzed by means of raytracing simulations. The starting configuration is the equinoctial paraboloid, which produces a point-like spot on the two equinox days only. On all other days of the year, this paraboloid is deformed in a suitable way in order to keep the spot as small as possible, but, even so, it is no longer a point-like spot. In the present work the simulated light distributions on the receiver, generated by the paraboloids (deformed or original), are compared. The results... [more]

Severe wellbore stability issues were reported while drilling in laminated formation with weak planes such as beddings. To accurately determine the safe mud weight according to the changing environment is of primary importance for safety control of drilling. Considering both the elastic and strength anisotropy of bedding formation, a novel theoretical model is established and the stress and failure around wellbores are analyzed. The accuracy and applicability of the theoretical model is verified by in situ field data. For the purpose of fulfilling real-time prediction, the method flowchart of programming is also provided. The results show that the model built can be conveniently used to predict the stress distribution, failure area, and collapse and fracture pressure while drilling, and rather good predictions can be made compared to real field data. In addition, the inhomogeneity of in situ stress and elastic parameters affect the upper limit of the safe mud weight window (SMWW) great... [more]

This article presents a solution that strengthens information security in critical infrastructure entities. Critical infrastructure plays a key role in the functioning of the state and the life of its citizens. Therefore, the protection of critical infrastructure is one of priorities in Poland. The aim of this article is to show that designated postal operators may become an important link in the process of information flow and cybersecurity. Based on their multiple-year experience and expended competences, the operators may provide digital services for entities responsible for the energy security infrastructure. Verification of this goal is necessary, since critical infrastructure is exposed to growing threats, both in the area of energy and other sensitive sectors of the economy. Research results presented in the article were obtained by conducting a CATI survey. The study used the purposeful selection method, which allows to influence the structure of a sample in the context of goal... [more]

Owing to the recent increase in the number of warning reports and alerts on the dangers of fine dusts, there has been an increasing concern over fine dusts among citizens. In spaces with poor ventilation, the occupants are forced to open the window to initiate natural ventilation via the direct introduction of the outside air; however, this may pose a serious challenge if the external fine-dust concentration is high. The lack of natural ventilation increases the indoor carbon dioxide (CO2) concentration, thus necessitating the installation of mechanical ventilation systems. This study analyzed the frequency of the application of mechanical ventilation systems in the Multi-purpose activity space of elementary schools, which are spaces where children require a higher indoor air quality than adults owing to the rapid increase in the CO2 concentration of the Multi-purpose activity space during activities. In addition, the architectural and equipment factors of the Multi-purpose activity sp... [more]

We examine the critical pore radius that results in critical gas saturation during pure methane hydrate dissociation within geologic porous media. Critical gas saturation is defined as the fraction of gas volume inside a pore system when the methane gas phase spans the system. Analytical solutions for the critical pore radii are obtained for two, simple pore systems consisting of either a single pore-body or a single pore-body connected with a number of pore-throats. Further, we obtain critical values for pore sizes above which the production of methane gas is possible. Results shown in the current study correspond to the case when the depression of the dissociation temperature (due to the presence of small-sized pores; namely, with a pore radius of less than 100 nm) is considered. The temperature shift due to confinement in porous media is estimated through the well-known Gibbs-Thompson equation. The particular results are of interest to geological media and particularly in the methan... [more]

Circular economy implementations tend to decrease the human pressure on the environment, but not all produce footprint reductions. That observation brings the need for tools for the evaluation of recycling processes. Based on the Exergy Footprint concept, the presented work formulates a procedure for its application to industrial chemical recycling processes. It illustrates its application in the example of cotton waste recycling. This includes the evaluation of the entire process chain of polyethylene synthesis by recycling cotton waste. The chemical recycling stages are identified and used to construct the entire flowsheet that eliminates the cotton waste and its footprints at the expense of additional exergy input. The exergy performance of the process is evaluated. The identified exergy assets and liabilities are 138 MJ/kg ethylene and 153 MJ/kg ethylene, reducing the Exergy Footprint by 75% and the greenhouse gas footprint by 43% compared to the linear pattern of polyethylene prod... [more]

Mountain huts are stand-alone micro-grid systems that are not connected to a power grid. However, they impact the environment by generating electricity and through day-to-day operations. The installed generator needs to be flexible to cover fluctuations in the energy demand. Replacing fossil fuels with renewable energy sources presents a challenge when it comes to balancing electricity generation and consumption. This paper presents an integration-and-optimization process for renewable energy sources in a mountain hut’s electricity generation system combined with a lifecycle assessment. A custom computational model was developed, validated with experimental data and integrated into a TRNSYS model. Five different electricity generation topologies were modelled to find the best configuration that matches the dynamics and meets the cumulative electricity demand. A lifecycle assessment methodology was used to evaluate the environmental impacts of all the topologies for one typical operatin... [more]

As a clean form of energy utilization, wind power is important for alleviating climate change. Although no direct carbon emissions occur in wind power generation, there exist upstream carbon emissions from manufacturing and installation, which have indirect effects on both the locations of wind farms and areas involved in upstream production and manufacturing. In this paper, based on Input−Output based Life Cycle Analysis (IO-LCA), we explored the lifetime carbon emissions of 378 wind farms in China that were still in operation in 2015. The regional distributions of carbon emissions from wind farms during the whole lifetime were depicted. The embodied carbon emission transfers from the location of the wind farm operation to upstream turbine manufacturing regions were traced. The net emission reduction benefits among regions were also calculated. Results show that carbon emissions mainly distribute in Liaoning, Inner Mongolia, and Tianjin in the turbine manufacturing stage, with a total... [more]

The Dongsha Island (DS) is located in the mid-northern South China Sea continental margin. The waters around it are underlain by the Chaoshan Depression, a relict Mesozoic sedimentary basin, blanketed by thin Cenozoic sediments but populated with numerous submarine hills with yet less-known nature. A large hill, H110, 300 m high, 10 km wide, appearing in the southeast to the Dongsha Island, is crossed by an ocean bottom seismic and multiple channel seismic surveying lines. The first arrival tomography, using ocean bottom seismic data, showed two obvious phenomena below it: (1) a low-velocity (3.3 to 4 km/s) zone, with size of 20 × 3 km2, centering at ~4.5 km depth and (2) an underlying high-velocity (5.5 to 6.3 km/s) zone of comparable size at ~7 km depth. MCS profiles show much-fragmented Cenozoic sequences, covering a wide chaotic reflection zone within the Mesozoic strata below hill H110. The low-velocity zone corresponds to the chaotic reflection zone and can be interpreted as of h... [more]

Due to the surge in load demand, the scarcity of fossil fuels, and increased concerns about global climate change, researchers have found distributed energy resources (DERs) to be alternatives to large conventional power generation. However, a drastic increase in the installation of distributed generation (DGs) increases the variability, volatility, and poor power quality issues in the microgrid (MG). To avoid prolonged outages in the distribution system, the implementation of energy management strategies (EMS) is necessary within the MG environment. The loads are allowed to participate in the energy management (EM) so as to reduce or shift their demands to non-peak hours such that the maximum peak in the system gets reduced. Therefore, this article addresses the complication of solutions, merits, and demerits that may be encountered in today’s power system and encompassed with demand response (DR) and its impacts in reducing the installation cost, the capital cost of DGs, and total el... [more]

The article presents the scope of issues related to the impact of the VUCA (volatility, uncertainty, complexity, ambiguity) environment on digital competences of management staff in power companies. Each company has to deal with its own individual and personalized VUCA world typical for the power industry. Unfortunately, some organizations are not aware of its existence, and therefore they do not identify the signals coming from the external environment while still working according to the developed patterns. The VUCA approach requires changing the competency model in enterprises and focusing on its strengths. On this basis, the research problem regarding power enterprises was formulated. The problem discussed in the article below concerns the undefined and undefined influence of the VUCA environment on the emerging digital competences of managers. In connection with the identification of the research problem in this area, an attempt was made to define the aim of the study, which is to... [more]

Inter-provincial power transmission in China solved the problem of electricity production and consumption spatial mismatch, which also facilitated Chinese green energy transition and sustainable development. Aiming to understand the spatial patterns and main driving factors, this paper accounted the aggregate carbon intensity per electricity produced by each province, built the inter-provincial Out−Destination matrixes of carbon emission embodied in power transmission among 27 provincial areas of 2006 and 2019, and quantitatively analyzed the change in spatial patterns of carbon flow and carbon intensity difference between power inward and outward provinces. We found that the inter-provincial power transmission has led to the reduction in the national average carbon intensity per electricity produced from 0.855 kg/kWh in 2006 to 0.628 kg/kWh in 2019 and the green energy transition of all provinces. The spatial morphology characteristics of carbon flow show the ‘three corridors of West-... [more]

The primary objective of this paper is to identify the possibilities of using sugar beet pulp as feedstock to produce a variety of added-value products. Such an application of the sugar production byproducts contributes to implementing circular bio-economy, which is a source of many economic, social, and environmental benefits. Specific objectives of this paper are: (1) Presenting the concept and meaning of circular bio-economy. (2) Characterizing properties of the sugar beet pulp from the perspective of using them as feedstock. (3) Determining the volume of production of the sugar beet pulp and the current methods of using them. (4) Determining the methods of obtaining attractive bioproducts and renewable energy from sugar beet pulp. Special attention was given to the amount of sugar beet pulp produced in Polish sugar refineries. Poland is among the European countries in which the volume of produced sugar is especially high. Therefore, the problem of appropriate waste management in th... [more]

Remote and hybrid working models and accelerated digitalization of the human resources processes were introduced in most organizations worldwide as a consequence of the COVD-19 pandemic. This digital revolution at the workplace was forced by extraordinary circumstances, thus its impact had not been anticipated before. This motivated the authors to study the new work reality. The research was based on a hypothesis that the digitalization of work and the human resources processes, approaches organizations to the sustainable development ideal. Sustainability is here understood as maintaining a balance between economic, environmental, and social factors. The authors analyzed the impact between the digital processes and the way of working on the following areas: CO2 emissions, creating plastic waste, saving energy, creating a gender-diverse and inclusive workplace. To verify the hypothesis, the authors used their own original and desk research. The original research was conducted within a B... [more]

This Special Issue titled “Advanced Wastewater Treatment and Biomass Energy” aims to compile the latest research and challenges in the field of wastewater treatment and energy production to reduce the impact of human activities on the environment [...]

In the last decades, a large focus is being placed on the sustainability and safety of the power transformer spectrum. Ester liquids, which have interesting properties such as high fire point and biodegradability, are gaining needed attraction. Since in-service condition, thermal aging deteriorates the physicochemical and electrical properties of liquid dielectrics, it is important to study their long-term behavior. In this contribution, the pre-breakdown and breakdown behavior of ester fluids (synthetic and natural) under AC stress are investigated. Important characteristics, such as partial discharge pre-inception voltage, partial discharge inception voltage, breakdown voltage, average streamer velocity, and inception electric field, were assessed. The influence of the radius of curvature (of high voltage needle electrode) as well as the thermal degradation of typical ester liquids are also discussed. Mineral oil was also included in the tests loop as a benchmark for comparative purp... [more]

This article presents the influence of climatic conditions on surface water quality. The research methodology, including physicochemical analysis from the Gołdapa and Bludzia rivers, is presented. The research lasted for two years. The results of the physicochemical studies of the Gołdapa and Bludzia rivers in early spring, spring, and autumn show that each of these seasons impacts the quality of surface waters. Moreover, it was proven that all the parameters are strongly correlated with the air temperature, the sum of daily precipitation, and water levels. For detailed analysis, the obtained results of own research were compared with meteorological and hydrological data from the last 15 years (2005−2021) for the region of north-eastern Poland. It was proven that temperature changes contribute to increased surface water pollution in the north-eastern part of Poland. Waters from areas that humans have not developed are of better quality than those that drain the urban area, which is ref... [more]

Economical and environmental concerns have forced the oil and gas industry to consider reusing flowback and produced water for fracturing operations. The major challenge is that the high-salinity of flowback water usually prevents its compatibility with several fracturing fluid additives. In this paper, the authors explored an economic and effective method to prepare guar fracturing fluids with different salinity waters. The main research idea was to use chelating agents to mask metal ions, such as calcium and magnesium, that are harmful to crosslinking. Firstly, a complexometric titration test was conducted to measure the chelating ability of three chelating agents. Secondly, through viscosity, crosslinking, and hanging tests, it was verified that the complex masking method could cope with the problem of high-valence metal ions affecting crosslinking. Thirdly, the preferred chelating agent was mixed with several other additives, including thickeners, crosslinkers, and pH regulators, t... [more]

In this study, three different environmentally friendly fouling mitigation technologies are suggested and are investigated in reverse electrodialysis (RED) to develop the most appropriate fouling mitigation technology for RED: applying direct current, flowing a solution with high salt concentration, and periodically switching river and seawater streams in RED. The quantitative level of anion exchange membrane fouling mitigation is evaluated in terms of the power density and the amount of power generation of RED. Applying a direct current electric field with higher voltage than 8 V was not allowed for fouling mitigation in the two-cell-pair bench RED stack due to decomposition of the redox couple. In comparison of the RED operations with two different fouling mitigation methods using firstly 40-min power generation during in-operation and 40-min fouling mitigation stage during out-of-operation as a cycle for 80 min and secondly 80-min forward power generation and 80-min backward power g... [more]

Landfills are elements of the waste management system, without possibility of further reclaiming, according to the requirements of a closed-loop economy, but with the possibility of transforming the area into other functions. The research combined monitoring of plant species, suggesting the composition of vegetation cover for pro-ecological management, analysis of functional and infrastructural incorporation of the landfill in the surrounding landscape, and proposals for reclamation and social application. An assessment of geotechnical safety was also made. Modernization of the landfill suggests that the pressure placed on other untouched locations should decrease. The designed space allows reintroducing socio-ecological life into this degraded area. Taking advantage of the character of the area, including variable development and significant landscape potential on the outskirts of a large city in the vicinity of protected areas, there is the possibility of creating new spatial quality... [more]

The increase in frequency and intensity of natural disasters is related to the changing global average temperature. Reducing greenhouse gas emissions and the extraction of natural resources is one of the solutions proposed by the European Green Deal and the 17 Sustainable Development Goals (SDGs) approved by the United Nations. The article presents research on municipal solid waste incineration bottom ash (MSWIBA), which is the basis for its circulation in the idea of the circular economy. The MSWIBA study presents differential thermogravimetry (DTG), glassy phase, and mortars using CSA and CEM I. The management of MSWIBA contributes to reducing greenhouse gas emissions and the extraction of natural resources.

This paper uses decomposition analysis to investigate the key contributions to changes in greenhouse gas emissions in different scenarios. We derive decomposition formulas for the three highest-emitting sectors: power generation, industry, and transportation (both passenger and freight). These formulas were applied to recently developed 1.5 °C emission scenarios by the Integrated Model to Assess the Global Environment (IMAGE), emphasising the role of renewables and lifestyle changes. The decomposition analysis shows that carbon capture and storage (CCS), both from fossil fuel and bioenergy burning, renewables and reducing carbon intensity provide the largest contributions to emission reduction in the scenarios. Efficiency improvement is also critical, but part of the potential is already achieved in the Baseline scenario. The relative importance of different emission reduction drivers is similar in the OECD (characterised by relatively high per capita income levels and emissions) and n... [more]

One of the most effective methods towards improving the environmental safety of combustion engines is the application of specially prepared water-fuel emulsions (WFE). The application of WFE makes it possible to reduce primary sulfur fuel consumption and reveals the possibility of capturing the pollutants from exhaust gases by applying condensing low-temperature heating surfaces (LTHS). In order to realize such a double effect, it is necessary to investigate the pollution processes on condensing LTHS of exhaust gas boilers (EGB), especially the process of low-temperature condensing a sulfuric acid vapor from exhaust gases to investigate the influence of condensing LTHS on the intensity of pollutants captured from the exhaust gases. The aim of this research is to assess the influence of the intensity of pollutants captured from exhaust gases by condensing LTHS in dependence of water content in WFE combustion. Investigations were carried out at a special experimental setup. The processin... [more]

The article aims to assess the effects of soil temperature measured in situ on the heat loss analyses of a building. Numerical analyses and in situ measurements of soil temperature profiles for real conditions under a residential building (profile I) in Poland and under the area outside the building (profile II) were performed. Based on the measurement results, a proprietary geometric model of the partition was proposed. The heat flux and heat flow results obtained for reliable models are 4.9% and 6.9% higher compared to a model based on a typical meteorological year for the wall−foundation system and 10.0% and 10.1% higher for the slab-on-ground structure for profile I. The adoption of temperatures from the area outside the building as the boundary condition (profile II) results in greater differences between the obtained results. The difference in heat flow obtained in the numerical analyses for profiles I and II is about 2 W/m2, both for the wall−foundation system and for the slab-o... [more]