In the course of our investigations, we burned high-quality logs as well as wood briquettes in a conventional, manually fed mixed-fired boiler, under different operating parameters. Based on the evaluation of the measurement results, there is a significant difference in terms of recoverable energy and carbon monoxide emissions for the two fuels burned in the same device at different air supply parameters. Studies have shown that a constantly changing position of the draft control door has an adverse effect on carbon monoxide emissions as well as the energy produced. In the case of a constant draft door setting, the preset values that can be considered ideal for energy yield and CO emissions were determined for the two fuel types. The obtained results were compared with the requirements according to the MSZ EN 303-5 standard.

In the construction of ecological civilization, green innovation has become an important driving force for the sustainable development of state-owned enterprises (SOEs). This paper uses panel data of state-owned listed enterprises from 2008 to 2019 to explore mixed-ownership reform’s influence on the green transformation of SOEs and its specific mechanisms. The results show that the diversity of mixed shareholders, the depth of mixed equity, and the restriction of mixed equity significantly promote the SOEs’ green innovation. Moreover, there are distinctions in the impact of the shareholding ratio of heterogeneous shareholders on green innovation. Only the increase in the shareholding ratio of foreign shareholders has a positive correlation with green innovation. The mechanism tests indicate that the mixed-ownership reform plays a governance role in the green transformation of SOEs by optimizing the reasonable allocation of environmental protection subsidies and propelling environmenta... [more]

Smart buildings use Internet of Things (IoT) sensors for monitoring indoor environmental parameters, such as temperature, humidity, luminosity, and air quality. Due to the huge amount of data generated by these sensors, data analytics and machine learning techniques are needed to extract useful and interesting insights, which provide the input for the building optimization in terms of energy-saving, occupants’ health and comfort. In this paper, we propose an IoT-based smart building (SB) solution for indoor environment management, which aims to provide the following main functionalities: monitoring of the room environmental parameters; detection of the number of occupants in the room; a cloud platform where virtual entities collect the data acquired by the sensors and virtual super entities perform data analysis tasks using machine learning algorithms; a control dashboard for the management and control of the building. With our prototype, we collected data for 10 days, and we built two... [more]

Any building’s design should sustain thermal comfort for occupants and promote less energy usage during its lifetime using accurate building retrofits to convert existing buildings into low-energy buildings so that the heating and cooling loads can be minimized. Regarding the methodology adopted in this research, an energy model of an educational building located at the German Jordanian University in Jordan was constructed utilizing DesignBuilder computer software. In addition, it was calibrated utilizing real energy consumption data for a 12-month simulation of energy performance. Subsequently, a computerized evaluation of the roles of building envelope retrofits or the adaptive thermal comfort limits in the reduction of the overall building energy consumption was analyzed. The results of the study show that the current building’s external wall insulation, roof insulation, glazing, windows, and external shading devices are relatively energy-efficient but with high cost, resulting in s... [more]

Although the Internet of Things (IoT), advanced manufacturing technologies, and cloud manufacturing contribute to developing a digital manufacturing ecosystem that enhances energy efficiency and resource utilization, manufacturing processes are vulnerable to timely production and delivery. The digital manufacturing systems in Industrial Revolution 4.0 (IR 4.0) minimized the human-technology interactions to foster productivity and material flow. However, there is scarce research to gauge the efficiency of these digital technologies in the entire manufacturing process; also, little is known about the collaborative efforts among countries to achieve sustainable manufacturing performance through the digitalization of the production process. Thus, this systematic review aimed to highlight the effectiveness of the digital manufacturing systems for sustainable product development and the collaborative research on the subject. We selected 52 research articles for this review by following the 2... [more]

Information and Communication Technologies (ICT) have scarcely been considered in studies on green consumption. Likewise, little attention has been paid to the effects of informational feedback on household energy ICT-related consumption. This paper aims to fill these gaps in the literature. Using microdata from a representative sample of the European Union population, this paper analyzes, in a novel way, whether the provision of information about the energy consumed by online services would make internet users change to a greener ICT consumption behavior. To assess this issue, Heckman type selection models are estimated. The results show that people’s concerns about environmental problems, their environmental activism and self-perceived efficacy as consumers are directly related to the influence that information provision exerts. We also find that frequent internet users and those with better digital skills are more willing to change their online behavior if given information on energ... [more]

So far, a lot of efforts have been put in life cycle assessments (LCA) of bioethanol production. There are many works that have assessed bioethanol production in different points of view to illustrate the environmental impacts. This study reviewed former LCA studies on bioethanol produced from various biomass resources by considering the effect of methodological components, technical pathways and feedstock provision on the result of LCA studies. The review evaluated 48 papers published 2002−2021 with a focus on studies that included a complete set of environmental impact categories. However, due to lack of harmony among studies, comparing the LCA results was challenging but the review indicated that the final results of studies are influenced by LCA methodological components, such as system boundary, functional unit, etc. Around 80% of the reviewed papers show the reduction in global warming potential, while contrary results have been found about increasing acidification, eutrophicatio... [more]

The protection of the environment and pollution control are issues of paramount importance. Researchers today are engrossed in mitigating the harmful impacts of petroleum waste on the environment. Lubricating oils, which are essential for the smooth operation of engines, are often disposed of improperly after completing their life. In the experimental work presented in this paper, deteriorated engine oil was regenerated using the acid treatment method and was reused in the engine. The comparison of the properties of reused oil, the engine’s performance, and the emissions from the engine are presented. The reuse of regenerated oil, the evaluation of performance, and emissions establish the usefulness of the regeneration of waste lubricating oil. For the used oil, total acid number (TAN), specific gravity, flash point, ash content, and kinematic viscosity changed by 60.7%, 6.7%, 4.4%, 96%, and 15.5%, respectively, compared with fresh oil. The regeneration partially restored all the lost... [more]

Phototactic and polarotactic aquatic insects, such as mayflies, can be drawn to electric lighting on bridges at night. Past research investigating the effect of light intensity, polarization, and spectrum on mayflies suggests that a combination of different techniques can reduce the number of mayflies attracted to bridges. Here, various lighting strategies are systematically tested on Veterans Memorial Bridge in Pennsylvania to investigate the effect of lighting on mayflies and address safety concerns caused by their mass crowding. Isolated trials on different parts of the bridge tested the effectiveness of correlated color temperature, chromaticity, ultraviolet radiation, shielding, and polarization. Results indicate that mayflies were more attracted to ultraviolet radiation, blue and green light, and polarized light than other lighting conditions. Shielding was minimally effective in reducing the number of mayflies on the bridge when supported by the change in light source spectrum.... [more]

One of the biggest problems of the modern economy is the depletion of traditional energy sources. Despite the fact that this problem was noticed several dozen years ago, steps to solve it were taken relatively recently. In December 2017, the European Union adopted a position on the directive, promoting the use of energy from renewable sources in all Member States. The EU has committed itself that by 2030, at least 27% of its energy consumption will come from renewable sources. On the one hand, it is a huge challenge, but on the other hand, it is an opportunity to achieve economic growth through innovation and a sustainable energy policy. On the Polish market, the chance to achieve the assumed plan is offered mainly by small companies that have been involved in innovative activities in the renewable energy sector in recent years. Innovation is an extraordinarily important determinant of the sustainable development of economies across the world. However, introducing it into business prac... [more]

The technology of waste-management thermal processing may pose a threat to the natural environment through the emission of harmful substances, such as CO, NOx, SO2, HCl, HF, total organic carbon (TOC) and dust, as well as dioxins and furans. Due to the advantages of thermal waste treatment, including the small volume of solid residue produced and possible thermal energy recovery, thermal waste treatment is widely applied. Continuous research is necessary to develop methods for reducing the risk of harmful substances being produced and methods for the effective removal of pollutants resulting from flue gases. This paper presents an analysis of the results and conditions of the experimental redesign of a thermal industrial waste (polypropylene) treatment plant. The purpose of the redesign was to improve the quality of gasification and afterburning processes taking place in the combustion and afterburner chambers (through the installation of an additional section), thus resulting in a red... [more]

The aim of this study is to examine the factors influencing the electricity consumption of urban households and to prove these with statistically significant results. The study includes 46 small and medium-sized towns in Hungary. The methodology of the study is mainly provided by a model that can be used for this purpose; however, the results obtained with the traditional regression method are compared with the results of another, more complex estimation method, the artificial neural network, which has the advantage of being able to use different types of models. The focus of our article is on methodological alignment, not necessarily the discovery of new results. Certain demographic characteristics significantly determine the energy demand of a household sector in a municipality. In this case, as the ratio of people aged 60 or over within a city rises by 1%, the urban household average energy consumption decreases by 61 kilowatt hours, and when it rises by 1%, the amount of pollutants... [more]

The meteorological environment is a determining factor in photovoltaic (PV) system feasibility (PVSF). To evaluate this impact more accurately, a quantitative analysis model based on multimeteorological factors and the Random Forest Regression model is proposed in this work. Firstly, an evaluation system is established to assess the impact. Then, to predict the indicators of the evaluation system, a parameter, i.e., performance ratio in sampling period, is defined. Secondly, a set of essential influences on the performance ratio in the sampling period is established through analyzing and reducing the discovered influences on the PV system performance. Finally, data from the Desert Knowledge Australia Solar Centre (DKASC) website are used to conduct the experiment. During the experiment, the sample set is cleaned using the model based on the cosine of the zenith angle. The functional relationship between the performance ratio in the sampling period and its essential influences is establ... [more]

Set against the United Nations Sustainable Development Goal 7, and the need to increase biomass Improved Cookstove (ICS) adoption and sustained use across the globe, this paper presents an evaluation of Practical Action Nepal’s (PAN) Results Based Financing for Improved Cookstove Market Development in Nepal (RBF) project, which was conducted between January and April 2020. Nepal has a long history of International Development assistance, yet 65.8% of rural households still use firewood as their primary source of energy. With this in mind we aimed to understand the barriers, enablers and engagement strategies for the adoption and sustained use of Improved Cookstoves (ICS), map key stakeholder role perceptions and interactions, and identify areas for improvement to increase the sustained use of ICS in the focus communities. This paper uses the methodological approach from the qualitative Technology Implementation Model for Energy (TIME) for the data collection and analysis elements. Our... [more]

This article presents the development, simulation and validation of the uncertainty cost functions for a commercial building with climate-dependent controllable loads, located in Florida, USA. For its development, statistical data on the energy consumption of the building in 2016 were used, along with the deployment of kernel density estimator to characterize its probabilistic behavior. For validation of the uncertainty cost functions, the Monte-Carlo simulation method was used to make comparisons between the analytical results and the results obtained by the method. The cost functions found differential errors of less than 1%, compared to the Monte-Carlo simulation method. With this, there is an analytical approach to the uncertainty costs of the building that can be used in the development of optimal energy dispatches, as well as a complementary method for the probabilistic characterization of the stochastic behavior of agents in the electricity sector.

The ecological and economic context determine the management goals of a modern enterprise, which are in line with the growing concern about the well-being of society caused by the effects of enterprises’ activities that are particularly harmful to the environment. This increases the need to search for new tools that will have the capacity to generate information supporting the decision-making process in the area of enterprise management in terms of ecological, economic, and social goals. For these reasons, synthetic measures of development were constructed on the basis of the set of diagnostic variables describing various aspects of sustainable development in the case. Based on the environmental synthetic indicators, it has been possible to point out the Polish voivodeships, in which enterprises that are particularly harmful to the environment were able to reduce the emissions of dust and gaseous pollutants in the 2005−2019 period. These changes were often accompanied by an increase in... [more]

The European Union’s environmental goal by 2050 is to become the first climate-neutral continent in the world. This means specific efforts for diversifying the energy mix and investing in low-carbon energy. Our study investigates the nexus among carbon emissions, energy consumption and mix, and economic growth in a modified framework that includes the contribution of inward foreign direct investments and international trade to lowering air pollution. We have used a two-step approach to explore in more detail the links between these variables in 24 EU countries over the period 1995−2018, followed by a panel VECM analysis. Our results indicate that there is a unidirectional link between economic growth and CO2 emissions, which should imply a decoupling of environmental improvement measures from the pace of economic growth. We also find bidirectional causal relationships between low-carbon energy shares in consumption and CO2 emissions, as well as between low-carbon energy share in consum... [more]

The necessity of developing renewable energy sources has contributed to increasing interest in developing the anaerobic digestion for producing biomethane since it both provides green energy and reduces disposal treatment. In this regard, to assure efficient water utilization by finding alternative water sources, sewage sludge collected from the wastewater treatment plant (WWTP) was recently investigated because it could represent a suitable resource for producing biomethane within the context of a circular economy. Therefore, this study aims at improving the current knowledge on the feasibility of biomethane production from sewage sludge by optimizing the logistic-supplying phase. In this regard, a GIS-based model was developed and applied to the Emilia-Romagna region to consider the existing networks of WWTPs and biogas systems to valorize sewage sludge for bioenergy production and minimizing environmental impact. The results of the GIS analyses allowed to localize the highest produc... [more]

Indoor climate comfort is important for school buildings. Nowadays, this is a topical problem, especially in renovated buildings. Poorly ventilated school classrooms create improper conditions for classrooms. A post-occupancy study was performed in a school building in temperate climatic conditions. The evaluation was based on the results of long-term monitoring of the natural ventilation strategy and measurements of the carbon dioxide concentration in the school classroom’s indoor environment. The monitoring was carried out in an old school building that was constructed in the 1970s and compared to testing carried out in the same school classroom after the building was renovated in 2016. Surprisingly, the renovated classroom had a significantly higher concentration of CO2. It was found that this was due to the regulation of the heating system and the new airtight windows. The occupants of the renovated classroom have a maintained thermal comfort, but natural ventilation is rather negl... [more]

The main objective of this article is to analyze the use of modern information technologies, referring to the example of smartphones, paying particular attention to selected cultural aspects of the phenomena that appear to play an important role in creating the concept of a smart city. The authors asked a research question: whether there is a difference in the perception of smart cities between Poland and Turkey in terms of a set of individual criteria and cultural differences in the context of globalization processes. The authors decided to compare the use of smartphones in an international environment. In their analysis, they examined Poland and Turkey, the countries which are characterized by markedly distinct culture and customs, but simultaneously present a similar level of IT development. The research was conducted in two stages at the turn of 2019 and 2020, and it involved more than 600 selected young people aged 18−25. It is important to mention that the study consulted the gro... [more]

Indoor Environmental Quality (IEQ) is a crucial issue in school buildings, because of the conditions that pupils and students are exposed to. From this assumption, potentialities of retrofit actions with Nearly Zero-Energy Building (NZEB) targets were analyzed in existing school buildings, focusing on the impact of such measures of IEQ. Numerical analyses in a transient regime for a typical school building were carried out to assess the impacts on the thermal comfort and Indoor Air Quality (IAQ). The study took into account several building configurations and three reference cities. The results showed severe overheating risks in retrofitted schools: the operative temperature increased by several degrees with respect to the existing configuration, leading to thermal discomfort for a relevant part of the observation period. Passive techniques, namely external solar protection devices and night ventilative cooling, were applied to assess their mitigation potential. Results showed that the... [more]

The paper deals with the characteristics of three different types of power train hybridization of forest logging machines and with the benefits of reducing environmental impacts by comparing new technology with more conventional, older technology. New hybridization options that could be implemented in forestry machines are also discussed. The paper divides a hybrid solution into three classes based on the energy used in the system of hybridization. First is an electro-hybrid system that uses an electric motor and battery or different storage device. The second, a hydraulic hybrid system, is a solution with a hydraulic accumulator, hydraulic motor, and pump. The third system is a combination of the electro-hybrid and hydraulic-hybrid system. The current technical and technological development of hybrid drive systems, as well as their components, has led to significant improvements in drive performance and thus better performance of the new generation of forest vehicles. Improved energy... [more]

It is necessary to carry out experiments on cores with different degrees of crack development when studying the seepage law of cracked reservoirs and evaluating cracks. The seepage experiment in the laboratory requires cores with different degrees of microcrack development; cores obtained via conventional drilling cannot meet the requirements, and the efficacies and evaluation methods of geological parameters used for artificial cracks are not perfect. In this study, cores are loaded using a triaxial gripper, and cracks are produced by changing the difference of stress; the relationship between the increased rate of permeability and the change in stress concentration is used to evaluate the degree of development of the crack in real time. The angle between the cracks and the maximum principal stress direction, calculated using the Mohr−Coulomb failure criterion, is 20−27.5°, which provides theoretical support for the process of crack creation. The experimental results show that the per... [more]

Space cooling is currently the fastest-growing end-user in buildings. The global warming trend combined with increased population and economic development will lead to accelerated growth in space cooling in the future, especially in China. The hot summer and cold winter (HSCW) zone is the most densely populated and economically developed region in China, but with the worst indoor thermal environment. Relatively few studies have been conducted on the actual measurements in the optimization of insulation design under typical intermittent cooling modes in this region. This case study was conducted in Chengdu—the two residences selected were identical in design, but the south bedroom of the case study residence had interior insulation (inside insulation on all opaque interior surfaces of a space) retrofitted in the bedroom area in 2017. In August 2019, a comparative on-site measurement was done to investigate the effect of the retrofit work under three typical intermittent cooling patterns... [more]

The work at hand assesses several driving factors of carbon emissions in terms of urbanization and energy-related parameters on a panel of emerging European economies, between 1990 and 2015. The use of machine learning algorithms and panel data analysis offered the possibility to determine the importance of the input variables by applying three algorithms (Random forest, XGBoost, and AdaBoost) and then by modeling the urbanization and the impact of energy intensity on the carbon emissions. The empirical results confirm the relationship between urbanization and energy intensity on CO2 emissions. The findings emphasize that separate components of energy consumption affect carbon emissions and, therefore, a transition toward renewable sources for energy needs is desirable. The models from the current study confirm previous studies’ observations made for other countries and regions. Urbanization, as a process, has an influence on the carbon emissions more than the actual urban regions do,... [more]