Throughout the world, wind energy is widely distributed as one of the most universal energy sources in nature, containing a gigantic reserve of renewable and green energy. At present, the main way to capture wind energy is to use an electromagnetic generator (EMG), but this technology has many limitations; notably, energy conversion efficiency is relatively low in irregular environments or when there is only a gentle breeze. A triboelectric nanogenerator (TENG), which is based on the coupling effect of triboelectrification and electrostatic induction, has obvious advantages for mechanical energy conversion in some specific situations. This review focuses on wind energy harvesting by TENG. First, the basic principles of TENG and existing devices’ working modes are introduced. Second, the latest research into wind energy-related TENG is summarized from the perspectives of structure design, self-power sensors and systems. Then, the potential for large-scale application and hybridization w... [more]

Real-time monitoring of energetic-environmental parameters in wastewater treatment plants enables big-data analysis for a true representation of the operating condition of a system, being still frequently mismanaged through policies based on the analysis of static data (energy billing, periodic chemical−physical analysis of wastewater). Here we discuss the results of monitoring activities based on both offline (“static”) data on the main process variables, and on-line (“dynamic”) data collected through a monitoring system for energetic-environmental parameters (dissolved oxygen, wastewater pH and temperature, TSS intake and output). Static-data analysis relied on a description model that employed statistical normalization techniques (KPIs, operational indicators). Dynamic data were statistically processed to explore possible correlations between energetic-environmental parameters, establishing comparisons with static data. Overall, the system efficiently fulfilled its functions, althou... [more]

While extensive research has gone into demand response techniques in data centers, the energy consumed in edge computing systems and in network data transmission remains a significant part of the computing industry’s carbon footprint. The industry also has not fully leveraged the parallel trend of decentralized renewable energy generation, which creates new areas of opportunity for innovation in combined energy and computing systems. Through an interdisciplinary sociotechnical discussion of current energy, computer science and social studies of science and technology (STS) literature, we argue that a more comprehensive set of carbon response techniques needs to be developed that span the continuum of data centers, from the back-end cloud to the network edge. Such techniques need to address the combined needs of decentralized energy and computing systems, alongside the social power dynamics those combinations entail. We call this more comprehensive range “carbon-responsive computing,” a... [more]

In this article, we propose a mathematical model using the port-Hamiltonian formalism for a satellite’s three-axis attitude system comprising fluid rings. Fluid rings are an alternative to reaction wheels used for the same purpose, since, for the same mass, they can exert a greater torque than a reaction wheel as the fluid can circulate the periphery of the satellite. The port-Hamiltonian representation lays the foundation for a posterior controller that is feasible, stable, and robust based on the interconnection of the system to energy shaping and/or damping injection components, and by adding energy routing controllers. The torques exerted by the fluid rings are modeled using linear regression analysis on the experimental data got from a prototype of a fluid ring. Since the dynamics of turbulent flows is complex, the torques obtained by the prototype lead to a simpler first approach, leaving its uncertainties to a controller. Thus, the attitude system model could be tested in a futu... [more]

The issues of renewable energy, energy crisis, and carbon reduction have caught people’s attention all over the world, and governments have put forth greater effort to proactively solve these problems. Electric transportation not only benefits the environment, but can also utilize renewable energy to prevent an energy crisis. Based on previous theoretical strands of the literature, this research integrates the technology readiness and acceptance model (TRAM) into the norm activation model (NAM) and proposes an integrated model denoted as TRA-NAM. It takes TRA-NAM as our theoretical foundation and aims to explore the effect of technology readiness and awareness of consequence on the intention toward using an electric scooter (ES). The results display that technology readiness positively influences perceived usefulness and perceived ease of use and further improves consumers’ intention toward adopting ES. In addition, personal norm mediates the relationship between awareness of consequen... [more]

Energy is crucial to economic development, but its production usually has a negative impact on the environment. This ambivalence leads to the need for methods to improve energy efficiency. Transportation is one of the largest global energy consumers. Therefore, improving the energy efficiency of transportation is crucial for sustainable development. The aim of this article is to show the limitations of energy management in railways, resulting from the model of market regulation. The question in this context is whether only technological methods can be used in railways to steer its energy efficiency, as is suggested by the existing research. Critical analysis, desk research and a case study of Polish railway undertaking were used to find an answer to the research question. The discussion of the results shows that the European regulatory system leads to greater complications in the field of energy management than in other global regions, where railways are also important for the economy.... [more]

The abandonment of the built heritage, as a result of functional or technological obsolescence or as a consequence of cultural, social, and economic trends, is steadily increasing. This great number of buildings, worldwide spread, offers a huge opportunity to reduce the environmental impacts related to the construction industry. Nonetheless, the recovery and reuse interventions that require the implementation of residual technological performance, to accommodate new uses, are not always environmentally neutral. Therefore, a new design approach needs to be developed so as to improve the buildings’ technological performance and enhance resources and energy already incorporated in buildings. The circular economy principles in the building sector, performance-based building design together with downcycling and upcycling theories are applied to develop a methodology aiming to reduce the environmental impacts within the rehabilitation and refurbishment design process. Starting from the build... [more]

Consideration of sustainability in product development is becoming increasingly important and encompasses many aspects of product design. In this study, a bibliometric review of recent sustainable product design publications using Web of Science and VOSViewer is carried out. The review indicates that the majority of publications concerning sustainable product design is oriented towards environmental science-led subject areas and production-led journals. Analysis of author keyword co-occurrences reveals that circular economy, life cycle assessment, sustainable management, and optimization are the most popular topics in sustainable product design research. The analysis also reveals that the researchers fail to link sustainability research to activities in product design, which leads to the lack of access to relevant research that can make products more sustainable. Building on the findings, the authors propose four future research directions that aim to guide researchers to better correl... [more]

The analysis of the economic efficiency of agriculture has been the subject of numerous studies. An economically efficient agricultural sector is not always environmentally efficient. Agriculture is a large emitter of greenhouse gases. The Intergovernmental Panel on Climate Change states that food production and agriculture are responsible for 21−37% of total global CO2 emissions. Due to the comprehensive assessment of the agricultural efficiency, it is worthwhile to apply to its measurement an integrated approach based on economic, energy and environmental aspects. These aspects were the main reasons for undertaking this research. The purpose of the study was to determine the economic, energy and environmental efficiency of agriculture in the EU Member States in 2019. The environmental analyses relate to the period 1990−2019. A total of 26 member states of the European Union (excluding Malta and Luxembourg) were selected for research. The sources of materials were Eurostat and the Eur... [more]

Although operators periodically measure the sludge volume index (SVI) to stabilize the bioreactor and solid−liquid separation during the wastewater treatment process, there is a problem of inconsistency attributed to the subjective judgment of the operator. This study aims to investigate the possibility of securing objective data by employing CdS (cadmium−sulfur) photoresistors for SVI measurements. The sedimentation velocity of settling sludge was measured using LED (Light Emitting Diode) lights at the same level as the installed CdS photoresistors. As a result of the experiment, the settling velocity of sludge in the CdS photoresistors’ installation position H1 to H8 (non-flocculent settling), H9 to H12 (discrete flocculent settling) and H13 to H18 (zone settling and compressive settling), was 0.594 mm/s, 0.180 mm/s and 0.056 mm/s, respectively. Through this study, it was confirmed that measuring sludge sedimentation using the CdS photoresistors is possible. If the measurement of sol... [more]

This study uses the fuzzy analytical hierarchy process (FAHP) method to prioritize contracting methods to determine the most suitable contract option for water and wastewater projects (WWP). Content analysis, a two-round Delphi survey technique, and a series of validation and reliability tests helped establish the 18 key criteria for FAHP analysis. Consequently, data collected from experts through a pairwise comparison questionnaire form the basis for the inputs for the FAHP analysis. Consequently, the final weightings were derived for each of the key criteria and available contracting methods. The results indicate that the bilateral, cooperative, and trilateral contracting methods are the most suitable for WWP in Iran, with the highest weighting. The study provides useful guidance for the top management of project firms in selecting the optimal contracting method for their projects and offers significant contributions from theoretical and practical perspectives.

It is important to effectively reduce carbon emissions and ensure the simultaneous adjustment of economic development and environmental protection. Therefore, we used Kaya identity to screen the factors influencing carbon emissions and conducted preliminary qualitative analyses, including grey relation analysis and linear regression analysis, on important variables to establish a vector autoregression (VAR) model based on their annual data to empirically analyze the influencing factors of carbon emissions. The results showed that economic growth effect, energy intensity effect and embodied carbon in foreign trade were the key factors affecting carbon emissions, among which the economic growth effect contributed the most. Accordingly, we propose countermeasures including technological innovation to reduce energy intensity, the development of new energy sources to improve energy structure, acceleration of industrial structure transfer, and optimization of trade structure.

In this paper, the issue of the deliberate aging of products by manufacturers is discussed. Deliberate aging consists in intentionally planning or designing a product with an artificially limited lifetime in order to force consumers to replace it faster. The resulting rapid acceleration of the cycle of obtaining and utilizing consumer goods has serious consequences in the form of negative externalities. For this reason, the conscious aging of products is now recognized as the cause of unjustified consumption, generating huge economic and social costs and leading to the devastation of the natural environment and excessive exploitation of natural resources. Thus, it is in clear contradiction to the model of sustainable development. The aim of this paper was to identify the purchasing attitudes of buyers in the durable goods market. For its implementation, a pilot questionnaire study, which covered a representative group of 354 respondents, was carried out. The results indicate that the f... [more]

District heating (DH) is an alternative technology to Individual Heating (IH) for satisfying end-user’s needs. This paper assesses the competitiveness of a DH network in the center of Italy from energy, environmental, and economic points of view considering both thermal power plant and end-users’ sides. On the thermal power plant side, the energy analysis considers the Primary Energy Saving (PES) and the specific energy (Esp) of the fuel actually exploited in the thermal power plant compared to its Low Heating Value (LHV), while the environmental analysis considers the avoided CO2 and the economic analysis considers the Energy Efficiency Certificates (EECs). Results showed that the current thermal power plant configuration with two boilers and a Combined Heat and Power (CHP) unit reaches a yearly PES of 21.3% as well as 1099 tCO2 avoided. From the economic analysis of the thermal power plant side, 829 EECs with an economic return of 207,222€ are obtained, while from the end-users’ side... [more]

In the paper, we present a method of automatic evaluation and optimization of production processes towards low-carbon-emissions products. The method supports the management of production lines and is based on unsupervised machine learning methods, i.e., canopy, k-means, and expectation-maximization clusterization algorithms. For different production processes, a different clustering method may be optimal. Hence, they are validated by classification methods (k-nearest neighbors (kNN), multilayer perceptron (MLP), binary tree C4.5, random forest (RF), and support vector machine (SVM)) that identify the optimal clusterization method. Using the proposed method with real-time production parameters for a given process, we can classify the process as optimal or non-optimal on an ongoing basis. The production manager can react appropriately to sub-optimal production processes. If the process is not optimal, then during the process the manager or production technologist may change the productio... [more]

Advanced brush seal technology has a significant impact on the performance and efficiency of gas turbine engines. However, in highly inlet swirling environments, the bristles of a brush seal tend to circumferentially slip, which may lead to aerodynamic instability and seal failure. In this paper, seven different front plate geometries were proposed to reduce the impact of high inlet swirl on the bristle pack, and a three-dimensional porous medium model was carried out to simulate the brush seal flow characteristics. Comparisons of a plane front plate with a relief cavity, plane front plate with axial drilled holes, anti-“L”-type plate and their relative improved configurations on the pressure and flow fields as well as the leakage behavior were conducted. The results show that the holed front plate can effectively regulate and control the upstream flow pattern of the bristle pack, inducing the swirl flow to move radially inward, which results in decreased circumferential velocity compo... [more]

This paper presents probabilistic methods to estimate the quantity of carbon dioxide (CO2) that can be stored in a mature oil reservoir and analyzes the uncertainties associated with the estimation. This work uses data from the Farnsworth Field Unit (FWU), Ochiltree County, Texas, which is currently undergoing a tertiary recovery process. The input parameters are determined from seismic, core, and fluid analyses. The results of the estimation of the CO2 storage capacity of the reservoir are presented with both expectation curve and log probability plot. The expectation curve provides a range of possible outcomes such as the P90, P50, and P10. The deterministic value is calculated as the statistical mean of the storage capacity. The coefficient of variation and the uncertainty index, P10/P90, is used to analyze the overall uncertainty of the estimations. A relative impact plot is developed to analyze the sensitivity of the input parameters towards the total uncertainty and compared with... [more]

Petroleum-derived substances (PDSs), which are one of the most significant sources of energy, have become key factors that affect soils and, consequently, plants. The aim of this study was to determine the subsequent effects of soil contamination by PDSs such as petrol (P), diesel fuel (DF) and used engine oil (EO), in addition to its bioremediation using a ZB-01 biopreparation, on the activities of antioxidising enzymes as well as on the content of antioxidants in the leaves of Vicia faba L. The effects on the growth of the plants and their chemical composition were also determined. The results showed that as many as five years after contamination, engine oil and diesel fuel adversely affected the growth of plants. PDSs caused a significant increase in the activity of peroxidase and an increase in the content of proline. The contamination of the soil with oils (EO and DF) resulted in a decrease in the content of nutrients (Ca, Mg and P) in the plants. DF also decreased the content of... [more]

The main purpose of this paper is to analyze and address the challenges of implementing green energy in Ukraine, in particular, to identify its advantages and disadvantages. The implementation of solar renewable sources—stations, panels, and batteries—is emphasized. The results of sociological surveys of Ukrainian public opinion on environmental issues, in particular, energy issues, are presented. The existence of public demand for renewable energy and the readiness of the population to use renewable energy sources are identified. A strategy for strengthening the country’s energy independence in the face of new globalization challenges is defined. General scientific methods as well as special methods were used in this paper: statistical analysis, secondary analysis of data from sociological studies of public institutions, and desk analysis of documents and reports from public services. In this paper, it is concluded that Ukraine is geographically and territorially attractive for green... [more]

The present investigation aims to devise a thermal management system (TMS) for electric vehicles able to improve on limitations like charging time and all-electric range, together with the safety and environmental impact of the chosen thermal medium. A research gap is identified, as focus is often on addressing system thermal performance without considering that the thermal medium must not only provide suitable performances, but also must not add risks to both passengers and the environment. Thus, this work proposes an innovative cooling system including graphite sheets and a Loop Heat Pipe, filled with Novec™ 649 as working fluid, due to its exceptional environmental properties (GWP = 1 − ODP = 0) and safety features (non-flammable, non-toxic, dielectric). A three-cell module experimental demonstrator was built to compare temperatures when the proposed TMS is run with Novec™ 649 and ethanol. Results of testing over a bespoke fast charge driving cycle show that Novec™ 649 gave a faster... [more]

Modern building materials must fulfill not only functional performance criteria but also reduce the environmental impact accompanied by their production. Within the past decades, fiber-reinforced materials have been found to be promising and durable materials that can be utilized in various fields. Among a wide range of reinforcement types, basalt fibers have been introduced as an alternative to broadly used steel fibers. As informed by the available literature, benefits linked with less energy-intensive production indicate a very good potential application of this material in terms of functional properties and, at the same time, a reduction in environmental burden. However, only a very limited amount of information is available on the actual impact of using basalt fibers in terms of environmental impact. In order to fill this gap, the present study describes, using Life Cycle Assessment, the environmental impacts associated with the production of basalt fibers. In order provide a more... [more]

As the number of users increased over the years, pioneering technologies and solutions in given areas ceased to be sufficient even in terms of performance. Therefore, there was a need for their development or even redesign and redefinition. One of the issues that undoubtedly has a huge impact on the current shape of the global network and the way information is processed in it is the issue of traffic balancing, especially the one in the server infrastructure related to the WWW service, providing users with the possibility of efficient and reliable web browsing. The paper presents a comparative analysis of selected open-source solutions used for traffic balancing in server infrastructures providing WWW service based on selected criteria. The designed architecture of the test environment and the test results of selected tools implementing the traffic-balancing functionality are presented. Methodologies, test plans, and comparison criteria are proposed. A comparative analysis of results b... [more]

Decarbonizing the world economy, before the most damaging effects of climate change become irreversible, requires substantially increasing renewable energy generation in the near future. However, this may be challenging in mature wind energy markets, where many advantageous wind locations are already engaged by older wind farms, potentially generating suboptimal wind harvesting. This research developed a novel method to systematically analyze diverse factors to determine the level of maturity of wind markets and evaluate the adequacy of wind farm repowering at regional and individual levels. The approach was applied to wind markets in the United States (U.S.), in which several states were identified as having diverse levels of maturity. Results obtained from case studies in Texas indicated a consequential number of wind farms that have reached their twenty-year end-of-life term and earlier obsolescence levels. The proposed approach aided in determining wind farms that may benefit from... [more]

The aim of this study was to determine the role of an installation based on biodrying of municipal waste in a Circular Economy by taking into account the quantitative and qualitative changes in its selectively collected waste stream. As a case study, the Mechanical-Biological municipal waste treatment installation in Olsztyn, Poland, was selected, which is equipped with a separate section for valorizing the selectively collected waste stream. The scope of the work included a complete mass balance of the waste treatment plant, an assessment of the technological efficiency of the municipal waste biodrying installation, and determination of the changes in the main waste from 2016 to 2020. This paper proposes an empirical method for estimating process loss during biodrying and provides many technological results. The average process loss was 23.47%, and on average, 88.9% of the waste produced by biodrying consisted of the Refuse-Derived Fuel fraction. The recovery of commercial assortments... [more]

Water is increasingly taking center stage when it comes to coping with climate change. Especially in urban areas, negative consequences from heavy rainfall events and prolonged dry periods are rising worldwide. In the past, the various tasks of urban water management were performed by different departments that often did not cooperate with each other (water supply, wastewater disposal, green space irrigation, etc.), as the required water supply was not a question of available water volumes. This is already changing with climate change, in some cases even dramatically. More and more, it is necessary to consider how to distribute available water resources in urban areas, especially during dry periods, since wastewater treatment is also becoming more complex and costly. In the future, urban water management will examine water use in terms of its various objectives, and will need to provide alternative water resources for these different purposes (groundwater, river water, storm water, tre... [more]