Phytoremediation is an emerging concept for contaminated soil restoration via the use of resilient plants that can absorb soil contaminants. The harvested contaminated biomass can be thermochemically converted to energy carriers/chemicals, linking soil decontamination with biomass-to-energy and aligning with circular economy principles. Two thermochemical conversion steps of contaminated biomass, both used for contaminated biomass treatment/exploitation, are considered: Supercritical Water Gasification and Fast Pyrolysis. For the former, the vast majority of contaminants are transferred into liquid and gaseous effluents, and thus the application of purification steps is necessary prior to further processing. In Fast Pyrolysis, contaminants are mainly retained in the solid phase, but a part appears in the liquid phase due to fine solids entrainment. Contaminants include heavy metals, particulate matter, and hydrogen sulfide. The purified streams allow the in-process re-use of water for... [more]

One of the most important climate change mitigation strategies is to exploit the potential of individual behavioral changes in order to reduce greenhouse gas (GHG) emissions, and the insights of behavioral economics are proving helpful in this regard. This contributes to improving traditional instruments, developing new ones related to choice architecture (nudges), and combining them within behavioral decarbonization intervention strategies. It is important, in terms of their effectiveness and efficiency, whether the instruments of such interventions are supported by citizens. This paper presents the results of a survey of Polish respondents’ (n = 1064) reactions to hypothetical nudges regarding the choice of a “green energy” supplier. The main research questions of the study are: how much civic support do these behavioral intervention tools have, and what is the importance of selected factors for their acceptance? The aim of the study is to present nudges as one of the strategies of p... [more]

This paper presents the method of determining the burning rate of fine-grained propellants based on the results of closed vessel tests. It is shown that in the case of fine-grained propellants, the standard methods of determining the burning rate fail. There are two reasons for this: imperfections of the grain shapes and the prolonged process of ignition due to a more developed surface than that of coarse grains at the same mass of the propellant. The value of the exponent in the burning law is estimated by the use of the so-called experimental form−function. The upper and lower limits of the value of the coefficient in the burning law are estimated. The accuracy of the proposed method is analyzed. Its validity is assessed by comparing the results of closed vessel tests analysis with accessible literature data.

Fourth industrial revolution is the introduction of ICT (mostly IoT) in industry and elsewhere, which enables the creation of cyber-physical systems, i.e., digital twins of reality. The application of widespread digitization of processes brings changes in terms of increased efficiency of processes, increased flexibility of production, and the possibility of realizing prosocial and pro-ecological goals, such as sustainable development, sustainable production and consumption, and reducing the consumption of increasingly expensive energy. Nowadays, the high autonomy of cyber-physical systems and benefits to society are expected by including human factors within the Industry 5.0 concept. Implementing the Fourth Industrial Revolution technologies and meeting the expectations of sustainable development also means new challenges for the knowledge and skills of industry employees, mainly engineers implementing modern solutions. Hence, the article’s aim is to identify the critical knowledge and... [more]

Bioenergy is one of the most important renewable-energy sources worldwide, accounting for more than two-thirds of the renewable-energy mix. Biomass accounted for 13−14% of the primary energy consumption in 2018, and by 2050, it is expected to account for 50% of the global primary energy consumption. This article studies the biomass potential in Iraq. The potential of this country to be one of the leading producers of bioenergy is discussed, remarking on the importance of agricultural crop waste. Nowadays, Iraq generates a great quantity of biomass every year. Unfortunately, instead of contributing to the energy industry and economic progress, these wastes are burned directly, potentially causing a slew of environmental issues. Based on earlier studies, the theoretical energy potential of Iraq agricultural wastes is assessed. It is concluded that 10 million tons of dry agricultural leftovers can create 115 PJ of energy per year. According to the findings of this study, 10 million heads... [more]

The energy industry, primarily based on the use of fossil fuels (e.g., coal and oil) is rapidly shifting toward renewable energy for securing sustainable resources. Thus, preparing for large wind power ramp events is essential to retain reliable and secure power systems. This study proposed a new statistical approach to predict wind power ramp events, and evaluated the performance of prediction. The empirical data, which is the observed wind power output data and wind speed data from Taebaek (South Korea) were used for analyzing ramp events and for evaluation. Based on the data analysis, a practical metric for evaluating the performance of wind power ramp events forecasting was developed and presented in detail. Notably, the accuracy of forecasting was evaluated through various metrics, whereas the normalized mean absolute error (NMAE) analysis demonstrated ≤ 10% values for all the analyzed months. In addition, a system review was conducted to check if the methodology suggested in this... [more]

In recent years, the study of natural polymer products such as methane hydrate inhibitors has attracted more and more attention in the scientific research field. In order to achieve environmentally friendly and economical methane hydrate inhibitors with high activity, four chitosan derivatives were successfully synthesized and their methane hydrate inhibition effects were compared with chitosan (CS) and carboxymethyl chitosan (CMCS). Under the conditions of 6 MPa, 1 °C and 400 rpm, the induction time of methane hydrate was prolonged by 7.3 times with the addition of 0.1 wt% CS. It was found that chitosan with high hydrophobicity could effectively prevent methane gas from entering the water solution and reduce the driving force of methane hydrates, resulting in the extension of hydrate induction time. The hydrate inhibition effect of CMCS could be improved by the introduction of hydroxypropyl-3-trimethylamine and N-2-hydroxypropyl-3-isooctyl ether groups based on the enhancement of the... [more]

The degree of autonomy of a battery-powered mobile device depends, among others, on the efficient use of energy by the powered devices. Using an example of electric drive systems of an orthotic robot, the authors present a method of reducing the energy demand of these systems by using a gear with a controlled ratio. The gear ratios are selected on the basis of special graphs illustrating the instantaneous energy consumption during drive operations. The simulation studies proved a possibility of achieving energy savings during the implementation of the robotic functions of the robot as high as 50%. The article presents the course and results of the research as well as the concept of their use while designing electric drive systems for mobile devices.

A 2-D numerical simulation model was established based on a small-sized metal hydride storage tank, and the model was validated by the existing experiments. An external cooling bath was equipped to simulate the heating effects of hydrogen absorption reactions. Furthermore, both the type and the flow rate of the cooling fluids in the cooling bath were altered, so that changes in temperature and hydrogen storage capacity in the hydrogen storage model could be analyzed. It is demonstrated that the reaction rate in the center of the hydrogen storage tank gradually becomes lower than that at the wall surface. When the flow rate of the fluid is small, significant differences can be found in the cooling liquid temperature at the inlet and the outlet cooling bath. In areas adjacent to its inlet, the reaction rate is higher than that at the outlet, and a better cooling effect is produced by water. As the flow rate increases, the total time consumed by hydrogen adsorption reaction is gradually r... [more]

In today’s cell production, the focus lies on maximizing productivity while maintaining product quality. To achieve this, the lamination of electrode and separator is one key process technology, as it bonds the electrode and separator to form mechanically resilient intermediate products. These mechanically resilient intermediates are necessary to enable high throughput processes. Although the lamination process has significant effects on the electrochemical performance of battery cells, it has not been sufficiently researched with regard to its process-product interdependencies. Therefore, this paper addresses the investigation of these interdependencies and proposes three characterization methods (grey scale analysis, high potential tests, electrochemical cycling and C-rate tests). The results of the three methods show that the lamination process with its process parameters (lamination temperature, lamination pressure and material feed rate) has an influence on both the properties of... [more]

Terrain-induced flow acceleration is presented for the summertime, peak power season at Lawrence Livermore National Laboratory’s Site 300 for the Hill Flow Study (HilFlowS). HilFlowS, designed as an adjunct field campaign to the Department of Energy’s Second Wind Forecasting Improvement Project (WFIP2), provides wind profile observations at a second location in complex terrain for validating numerical atmospheric model simulations and for better understanding flow behavior over hills for wind power generation. One unique feature of HilFlowS was the inclusion of an undergraduate university student who helped plan and execute the experiment as well as analyze wind data from two remote sensing laser detection and ranging (lidar) instruments deployed along parallel ridgelines. HilFlowS examines the trend of building higher into the atmosphere for the purpose of increasing wind turbine power production and evaluates the wind resource in the Altamont Pass Region of Northern California for a... [more]

Massive reinforced concrete (MRC) structures are utilized in a variety of applications where both mechanical and thermal properties are of concern. A 1:2 large-scale test model of the steel-lined reinforced concrete penstock (a kind of MRC) and a coupled thermomechanical numerical analysis are both implemented to investigate the thermomechanical effects on structural behavior. Three different temperature fields and eight temperature gradients are selected to explore how the temperature affects the crack width, steel stress, and deformation. The results show that the numerical simulation results are consistent with the experimental results and that this method can be applied to other similar MRC structure analysis. The thermal effect can cause 10−3~10−2 mm thermal crack width and ±45 MPa thermal stress and this may lead the total crack width to exceed the limited value and the reinforcement stress beyond the yield strength. Consequently, the influence of the thermomechanical loads canno... [more]

This article is part of a scientific research project dedicated to the study of plants generating electricity from hydraulic sources by exploiting the technology of inverted flow centrifugal pumps, also known as PAT. The main purpose is to provide a contribution to the methodologies already existing in the literature, creating a one-dimensional model capable of predicting the characteristic curves of the machine, in both operating modes, without knowing its geometry. The first part of the work is therefore focused on the description of the fluid dynamic model, capable of determining the losses in the various sections of the machine, using different calculation approaches. The development of this model was carried out using a set of six centrifugal pumps, measured at the DIMEG Department of the University of Calabria and at the University of Trento. For this range of pumps, the characteristic curves were therefore obtained, both in pump and turbine operation. The second part of this wor... [more]

The fulfillment of the sustainable development goals of the United Nations (UN) in remote communities undoubtedly goes through the consequent development of the energy supply system (ESS). Structuring a procedure for modeling the ESS, according to development requirements, is vital for decision making. This publication reviews the main methods for designing local development programs that apply a sustainable livelihoods approach and a group of modeling tools for ESS. The necessary criteria are verified to structure a model that integrates the expectations of sustainable development, through the indicators of sustainable livelihoods (SLs), with the requirements of the ESS and the use of available renewable energy resources. In the review carried out, it is found that the methods of analysis and planning of sustainable local development are disconnected from the models for energy planning. On the other hand, the relationship of the indicators for calculating SLs with the characteristics... [more]

Cosmic ray muon tomography has been recently explored as a non-destructive technique for monitoring or imaging dense well-shielded objects, classically not achievable with traditional tomographic methods. As a recent example of technology transition from high-energy physics to real-world engineering applications, cosmic ray muon tomography has been used with various levels of success in nuclear nonproliferation. However, present muon detection systems have no momentum measurement capabilities and recently developed muon-based radiographic techniques rely only on muon tracking. This unavoidably reduces resolution and requires longer measurement times thus limiting the widespread use of cosmic ray muon tomography. Measurement of cosmic ray muon momenta has the potential to significantly improve the efficiency and resolution of cosmic ray muon tomography. In this paper, we propose and explore the use of momentum-dependent cosmic ray muon tomography using multi-layer gas Cherenkov radiator... [more]

Nearly 40% of the world’s population lives within 100 kilometres of the coast with the risk that this implies in terms of exposure to the effects of climate change. Ocean energy, according to the IPCC (Intergovernmental Panel on Climate Change) in 2019, has been identified as one of the measures for mitigating these effects. In addition, ocean energy can play an essential role in achieving some of the SDGs (Sustainable Development Goals) set at the Paris Climate Summit in 2015, namely SDG 7 (clean and affordable energy) and SDG 13 (climate action) and could have a substantial impact on others such as SDG 1 (poverty eradication), SDG 2 (end hunger), SDG 5 (gender equality), SDG 6 (universal energy access), SDG 8 (promote sustainable economic growth), SDG 9 (build resilient infrastructure), SDG 14 (sustainable conservation of oceans and seas) and SDG 17 (promote sustainable development cooperation). There are several projects under development around the world aimed at extracting energy... [more]

As the time spent by people indoors continues to significantly increase, much attention has been paid to indoor air quality. While many IAQ studies have been conducted through field measurements, the use of data-driven techniques such as machine learning has been increasingly used for the prediction of indoor air pollutants. For the present study, the concentrations of indoor air pollutants such as CO2, PM2.5, and VOCs in child daycare centers were predicted by using an artificial neural network model with three different training algorithms including Levenberg−Marquardt, Bayesian regularization, and Broyden−Fletcher−Goldfarb−Shanno quasi-Newton methods. For training and validation, data of indoor pollutants measured in child daycare facilities over a 1-month period were used. The results showed all the models produced a good performance for the prediction of indoor pollutants compared with the measured data. Among the models, the prediction by the LM model met the acceptable criteria... [more]

In this study, to use carbon nanotubes (CNTs) as a conductive material instead of carbon black in cathode electrodes, their dispersions were prepared in 1-Methyl-2-pyrrolidinone (NMP) solvent by using an ultrasonic horn, and their dispersion stability was analyzed using CNTs on the formation of the network between cathode electrode constituent materials comprised of cathode material, CNTs, and current collectors, and their correlation with electrochemical performance results were investigated using various analytical techniques. Particularly, in the analysis, terahertz time domain spectroscopy (THz-TDS), a new non-destructive analysis method, was used to analyze and compare the various optical properties of the cathode’s slurries that co-existed with CNTs and cathode material, suggesting the suitability of its analytical use in the field of materials dispersion and the slurry manufacturing process for lithium-ion batteries (LIBs). In the investigated results, the sample with the highes... [more]

This paper presents an analysis of the literature that studies the possibility of sewage sludge being used in the cement industry to reduce carbon dioxide emissions from cement production and thus solve the problem of disposing of sewage sludge so that it is no longer stored, avoiding soil pollution with heavy metals, and reducing pressure on the environment. The ash of sewage sludge is a good pozzolanic material, because when it is finely ground, it can be used as a partial substitute for Portland cement. This reduces waste storage costs. Sewage sludge ash was mixed with cement, and it was analyzed to determine whether the paste obtained could be used as a raw material in the cement industry. The presented results are on the hydration characteristics of the sewage sludge ash, the compressive strength of the cement determined after different days, the workability of the cement, and the porosity of the cement paste and the ash.

Mitigating haze pollution is of practical significance to the green economy, and the development of digital finance may help achieve this goal. However, the effect of digital finance on haze pollution has not been systematically explained. Based on Chinese prefectural panel data for the 2011−2016 period, this study on haze concentration, technological innovation, and digital inclusive finance index as the dependent variable, mediating variable, and the core independent variable, respectively, investigated whether digital finance has improved haze pollution control in China using fixed effect (FE) and random effect (RE) models, a mediating effect model, a threshold panel model, and a dynamic spatial Durbin model (SDM). Four key results were obtained. (1) Digital finance significantly decreased haze pollution. After accounting for potential endogeneity, this conclusion was still valid. (2) The analysis of the influencing mechanism showed that digital finance was conducive to haze reducti... [more]

There are myriad questions that remain to be answered in greenhouse gas (GHG) emissions trading. This article addresses carbon dioxide (CO2) emission factors and carbon losses from heavy equipment that is used to transport ores. Differences occurred between the Intergovernmental Panel for Climate Change (IPCC) emission factor and those that were obtained by considering incomplete combustion and on-site exhaust concentration measurements. Emissions from four off-road vehicles were analyzed. They operated at idle (loading, unloading, and queuing) and in motion (front and rear, loaded and unloaded). The results show that the average CO2 emission factors can be as low as 64.8% of the IPCC standard value for diesel fuel. On the other hand, carbon losses can be up to 33.5% and energy losses up to 25.5%. To the best of the authors’ knowledge, the method that was developed here is innovative, simple, useful, and easily applicable in determining CO2 emission factors and fuel losses for heavy ma... [more]

Lithium-ion battery devices are essential for energy storage and supply in distributed energy generation systems. Robust battery management systems (BMSs) must guarantee that batteries work within a safe range and avoid the damage caused by overcharge and overdischarge. The state-of-charge (SoC) of Li-ion batteries is difficult to observe after batteries are manufactured. The hysteresis phenomenon influences the existing battery modeling and SoC estimation accuracy. This research applies a terminal sliding mode observer (TSMO) algorithm based on a hysteresis resistor-capacitor (RC) equivalent circuit model to enable accurate SoC estimation. The proposed method is evaluated using two dynamic battery tests: the dynamic street test (DST) and the federal urban driving schedule (FUDS) test. The simulation results show that the proposed method achieved high estimation accuracy and fast response speed. Additionally, real-time battery information, including battery output voltage and SoC, was... [more]

Fluctuations in renewable energy production, especially from solar and wind plants, can be solved by large-scale energy storage. One of the possibilities is storing energy in the form of hydrogen or methane−hydrogen blends. A viable alternative for storing hydrogen in salt caverns is Lined Rock Cavern (LRC) underground energy storage. One of the most significant challenges in LRC for hydrogen storage is sealing liners, which need to have satisfactory sealing and mechanical properties. An experimental study of hydrogen permeability of different kinds of polymers was conducted, followed by modeling of hydrogen permeability of these materials with different additives (graphite, halloysite and fly ash). Fillers in polymers can have an impact on the hydrogen permeability ratio and reduce the amount of polymer required to make a sealing liner in the reservoir. Results of this study show that hydrogen permeability coefficients of polymers and estimated hydrogen leakage through these materials... [more]

With the increasing need for cooling and the concerns for pollution due to fossil fuel-based energy use, renewable energy is considered an add-on to cooling technologies. The climatic condition in the Middle East, analyzed in this paper, provides the potential to integrate solar energy with the cooling system. Due to the availability of various solar energy and cooling technologies, multiple configurations of solar-cooling systems can be considered to satisfy the cooling demand. The research presented in this paper aims to assess and compare these configurations by considering the energy prices and the installation area. The proposed model is formulated in Mixed-Integer Linear Programming and optimizes the holistic system design and operation. The economic, renewable energy use, and environmental performances of the optimal solution for each configuration are analyzed and compared to the base grid-DCS configuration. Results show that the electricity tariff and the available installatio... [more]

This article aims to present changes in the use of electricity by service companies, resulting from regulations within the framework of increasing energy efficiency from the perspective of the implementation of the European Green Deal strategy. To achieve the above goal, the following research question was formulated: to what extent did the COVID-19 pandemic affect the implementation of energy transformation and electricity consumption among the surveyed group of recipients? It should be noted that, so far in the global environment, more and more electricity has been used every year, and this tendency is still continuous and growing. Therefore, in European Union countries, measures have been taken to balance demand and its rational use, resulting from the implementation of the European Green Deal strategy. According to the strategic goal of the indicated policy, EU countries are obliged to implement a sequence of actions enabling their transformation into a modern, resource-efficient,... [more]