In hot and dry regions such as the Gulf Cooperation Council (GCC) countries, the cooling demand is often responsible for more than 70% of electricity consumption, which places a massive strain on the electricity grid and leads to significant emissions. Solar thermal driven Silica-Gel/Water adsorption chillers, used for space cooling, could provide low carbon emission cooling and reduce the reliance on grid electricity. However, a meticulous design is required to make this both economically and environmentally beneficial. This paper aims to evaluate the solar thermal adsorption chiller performance based on large-scale cooling demand through a TRNSYS simulation for 1 year of operation. The proposed system consists of two main parts: first, the solar loop with evacuated tube solar collectors; and second, the adsorption cooling system with a silica-gel/water adsorption chiller. A neighbourhood of 80 typical 197 m2 villas in Riyadh, the capital city of the Kingdom of Saudi Arabia (KSA), was... [more]

The present work aims to provide a technical, economic, and environmental analysis on the electric accumulators used for electric mobility (pure electric, hybrid, full hybrid and/or mild hybrid) to reduce the environmental, social and economic impacts generated by private vehicles. Initially, the scenarios for the development of electric mobility and the regulatory context were assessed. Attention has been focused on the batteries used in electric vehicles and the technological aspects related to their charging operations. With regard to the economic aspects, the evolution of battery costs in relation to capacity and size has been highlighted in recent years. The advantages related to the containment of environmental impacts are highlighted considering the aspects related to the end of life of the batteries themselves. As retrofitting ICE vehicles by electric motor currently represents a potential transition solution to improve the shift towards the widespread adoption of electric vehi... [more]

The Sustainable Development Goals (SDGs) represent a bridging point between the old, neoclassical, growth-based model of the economy and newer, emerging paradigms, such as the well-being economy. The importance of growth in Gross Domestic Product (GDP) is recognized within the SDGs, however, in addition, Target 19 of Goal 17 advocates the adoption of alternative measures of economic well-being. The Genuine Progress Indicator (GPI) has been found to be the indicator of alternative economic well-being most aligned with the SDGs. On the basis that increased, high-quality energy use leads to expanded macro-economic activity, as measured by GDP, this study conducts a conceptual exploration of the extent to which the pursuit of sustainable energy development (SED) can enhance GPI outcomes. Based on a recent Icelandic GPI study, a total of 46 SED themes were found to be linkable to 16 of its 39 sub-indicators, including 8 cost deductions and 7 benefit additions. The frequency of these was as... [more]

At present, primary power generation depends on non-renewable energy resources, which will become extinct. Solar is the best option in renewable energy sources to achieve clean and green power extraction. Solar PV transforms light energy into electrical energy. However, the output power of solar PV changes with solar insolation. It is also affected by environmental factors and the shading effect. One of the key factors that can reduce the PV system output power is partial shading condition (PSC). The reduction in power output not only depends on shaded region but also depends on pattern of shading and physical position of shaded modules in the array. Due to PSCs, mismatch losses are induced between the shaded modules which can cause several peaks in the output power-voltage (P-V) characteristic. This article describes the non-symmetrical reconfiguration technique and compares it with the primary total cross tied connection. The performance of non-symmetrical reconfiguration techniques... [more]

The development of wastewater treatment methods and the processing of sewage sludge is associated with the search for new, efficient and technologically justified solutions, the use of which will be an alternative to the systems used thus far [...]

This paper presents the results of experimental research and mathematical modelling in terms of the influence periodic dynamic instabilities have on condensation phase change in R1234yf and R1234ze refrigerants in tubular minichannels. The main reason for this research was the fact that under the Montreal Protocol (1986), as well as Regulation No 517/2014 of the European Parliament and of the Council of 16 April 2014, the F-gases such as hydrofluorocarbons (HFC), perfluorocarbons (PFC), sulphur hexafluoride, and other agents containing fluorine have to be withdrawn. This includes one of the most commonly used refrigerants—R134a—which, since 1 January 2017, has already been withdrawn. It also includes the R404A refrigerant. R1234ze and R1234yf are suggested as substitutions for R134a. The basic parameters determining the application of those agents are their global warming potential (GWP) indicator, which is below 150, and reduction in fluorinated greenhouse gases emission by a third, s... [more]

Phosphorus (P) is a limiting nutrient mined from non-renewable sources. P is needed to stimulate trees growth in a forest plantation. P-fertilizer addition in the tropical forest field causes P-leaching flux to watershed and induces eutrophication. The high C contained in meranti (Shorea sp.) biochar can avoid the P-leaching process in the soil with a strategic application method. However, the biochar application method is poorly examined. This research aimed to develop a biochar application method to sequestrate P from the environment and examine its effect on the growth of sengon (Falcataria moluccana). Shorea sp. biochar pyrolyzed at 400 °C and 600 °C were added at a dosage of 0 t ha−1, 25 t ha−1, and 50 t ha−1 for six months in the field. The biochar was placed 20 cm under topsoil without soil mixing. This application method significantly increased total P in the soil without any P-fertilizer addition. The results showed that biochar pyrolyzed at 600 °C and a dosage of 25 t ha−1 in... [more]

The process of cutting laminations from which the cores of electric machines are built causes a change in their magnetic properties and losses, which can significantly affect machines’ parameters, mainly losses of power and efficiency. Electric motors are a significant consumer of electricity; therefore, the problem of increasing their efficiency is fundamental from the point of view of environmental impact. The subject of the work is the study of the influence of punching and laser cutting on the magnetization and loss characteristics of sheets, taking into account the phenomenon of magnetic anisotropy. For this purpose, samples cut in different directions were tested. As the direction of the field action in the motor core varies in different parts of the machine and time moments, it was investigated how to obtain average characteristics for different directions of magnetization. Then, a simplified method for determining the characteristics of punched sheets of various widths based on... [more]

An important instrument for achieving smart and high-performance buildings is Machine Learning (ML). A lot of research has been done in exploring the ML models for various applications in the built environment such as occupancy prediction. Nevertheless, the research focused mostly on analyzing the feasibility and performance of different supervised ML models but has rarely focused on practical applications and the scalability of those models. In this study, a transfer learning method is proposed as a solution to typical problems in the practical application of ML in buildings. Such problems are scaling a model to a different building, collecting ground truth data necessary for training the supervised model, and assuring the model is robust when conditions change. The practical application examined in this work is a deep learning model used for predicting room occupancy using indoor climate IoT sensors. This work proved that it is possible to significantly reduce the length of ground tr... [more]

Interest in and acquisition of energy-efficient items and pro-environmental products and the scale of these purchases depend on consumer attitudes, especially those related to beliefs that such products are usually more expensive than their nonenergy-efficient counterparts. However, green skepticism is a phenomenon that weakens the willingness to buy both energy-efficient and pro-environmental products. This skepticism is enhanced by the phenomenon of greenwashing, which has become a popular way of competing, whereby companies strive to appear to be more environmentally friendly than they are. Therefore, we wanted to investigate consumer attitudes toward energy-efficient products and environmentally friendly purchases. We conducted a survey using a computer-assisted web interview (CAWI) technique throughout Poland. The research sample included 1000 individuals and was representative of gender, age, and place of residence. The results of our study showed that women, people with a higher... [more]

The pollution caused by gas flaring is hazardous to the health of flora, fauna, and humans settled around the flaring site. Gas flaring also incurs economic loss as natural gas, an energy source, is wasted in flares. Furthermore, the unreliable electrical infrastructure is a roadblock for oil and gas companies attempting to achieve their production targets. This paper presents a framework to design hybrid energy systems (HES) which utilize the gas flare waste along with the locally available renewable energy sources to generate electricity. A novel dispatch strategy to suit the requirements of the oil and gas fields has been used for real-time simulations and optimization of the HES. As a test case, six different hybrid energy configurations, modelled for two gas flaring sites, Lakwa and Geleky in Assam—India, were analyzed and compared on the basis of economic and environmental factors. The best suitable configuration comprised 2000 kW solar photovoltaic (PV) panel sets, one 200 kW ga... [more]

This study discusses how to facilitate the barrier-free circulation of energy big data among multiple entities and how to balance the energy big data ecosystem under government supervision using dynamic game theory. First, we define the related concepts and summarize the recent studies and developments of energy big data. Second, evolutionary game theory is applied to examine the interaction mechanism of complex behaviors between power grid enterprises and third-party enterprises in the energy big data ecosystem, with and without the supervision of government. Finally, a sensitivity analysis is conducted on the main factors affecting co-opetition, such as the initial participation willingness, distribution of benefits, free-riding behavior, government funding, and punitive liquidated damages. The results show that both government supervision measures and the participants’ own will have an impact on the stable evolution of the energy big data ecosystem in the dynamic evolution process,... [more]

The V2X environment poses many challenges to emerging wireless communication systems, while it is crucial to ensure the efficiency and safety of road users. Requiring continual localization of the surroundings and accurate obstacle detection while providing high reliability in dense networks and low latency in high-mobility environment communication systems imposes a challenge to the driver-assistance field given that we are overly limited in terms of frequency bands and resources. Hence, pooling of the available frequency resources between different applications can help increase the spectral efficiency. A new collaborative approach multiplexed in the time domain, namely RadCom, which can be described as a joint radar and communication system that performs both vehicle-to-everything communication and detection of the neighboring obstacles in the vehicular environment, has been proposed to overcome the limitations of the existing conventional radar system. Based on orthogonal frequency... [more]

Ensuring the comfort and health of occupants is the main objective of properly functioning building systems. Regardless of the season and building types, it is the priority of the designers and building managers. The indoor air parameters affect both the well-being and health of users. Furthermore, it could impact the effectiveness of their work and concentration abilities. In hotel facilities, the guests’ comfort is related directly to positive opinions or customer complaints, which is related to financial benefits or losses. The main goal of this study is the analysis of the indoor environmental quality in guests’ rooms, based on the example of a hotel in Poland. The article assesses the variability of air parameters, including temperature, humidity, and carbon dioxide concentrations, and the acceptability of indoor conditions. The research was carried out in November 2020. Based on the collected data, the dynamics of changes of selected air parameters were analyzed. The article anal... [more]

The adsorptive removal of dyes from industrial wastewater using commercially available adsorbents is not significantly efficient. Metal−organic frameworks (MOFs) offer outstanding properties which can boost the separation performance over current commercial adsorbents and hence, these materials represent a milestone in improving treatment methods for dye removal from water. Accordingly, in this paper, the recent studies in the modification of MOF structures in dye removal from the aquatic environment have been discussed. This study aims to elaborate on the synthetic strategies applied to improve the adsorption efficiency and to discuss the major adsorption mechanisms as well as the most influential parameters in the adsorptive removal of dyes using MOFs. More particularly, the advanced separation performance of MOF-based adsorbents will be comprehensively explained. The introduction of various functional groups and nanomaterials, such as amine functional groups, magnetic nanoparticles,... [more]

Applying microbial fuel cell (MFC) technology for eco-remediation of Cr(VI) pollution from a subsurface environment has great scientific value and practical significance due to its promising advantages of pollutant remediation and renewable energy generation. The aim of the current review is to summarize the migration characteristics of Cr(VI) in a subsurface soil/water environment and investigate the factors affecting the MFC performance for synchronous Cr(VI) remediation and power generation, and sequentially highlight diverse challenges of MFC technology for in situ remediation of subsurface groundwater and soils. The critical review put forward that Cr(VI) removal efficiency and energy production of MFC can be improved by enhancing the adjustability of cathode pH, setting potential, modifying electrode, and incorporating other technologies into MFC. It was recommended that designing typical large-scale, long-term continuous flow MFC systems, adding electron shuttle media or constru... [more]

Dairy farms are challenged to increase productivity while achieving environmental sustainability, where greenhouse gas (GHG) emissions are at the center of the discussion. The U.S. dairy industry leadership has committed to a Net Zero Initiative to achieve GHG neutrality, but the specifics on how to achieve this are still uncertain. Life cycle assessment methods were used to quantify GHGs and net energy intensity (NEI) of a large (1000 cows) and a small (150 cows) farm in Wisconsin. The GHGs are 1.0 and 1.3 kg CO2-eq/kg FPCM and the NEI is 2.4 and 3.2 MJ/kg FPCM for the large and small farm, respectively. The GHG benefits from anaerobic digestion (AD, sized to process all manure on both farms) and PV (sized to match AD electricity production) are not enough to achieve GHG neutrality. Increasing the capacity of these systems showed that AD is more cost-effective for the larger farm, but the challenges and costs related to securing and disposing the extra manure needed for energy product... [more]

It has been identified that improving building energy efficiency is an effective method to reduce greenhouse gas (GHG) emissions. Although standards have been established to satisfy a building’s minimum energy demand while ensuring the comfort of its residents, they are difficult to implement in mixed-humid regions. This study proposes a hybrid ventilation strategy that can comprehensively reduce cooling, heating, and ventilation energy in mixed-humid climate regions to significantly decrease the primary energy demand and reduce the impact of buildings on the environment. This study evaluated the changes in energy saving potential and thermal comfort according to the extension of the natural ventilation period and passive strategies, such as decentralized ventilation. Changes in indoor air temperature, operative temperature, and PMV for each strategy were analyzed. As a result, extending the natural ventilation and the decentralized ventilation strategies can save 32% and 34% of the bu... [more]

Ventilation is becoming increasingly important to improve indoor air quality and prevent the spread of COVID-19. This study analyzed the indoor air quality of office spaces, where occupants remain for extended periods, among multi-use facilities with an increasing need for ventilation system application. A “tool for office space CO2 prediction and indoor air quality improvement recommendation” was developed. The research method was divided into four steps. Step 1: Analysis of indoor air quality characteristics in office spaces was carried out with a questionnaire survey and indoor air quality experiment. Based on the CO2 concentration, which was found to be a problem in the indoor air quality experiment in the office space, Step 2: CO2 concentration prediction tool for office spaces, which requires inputs of regional and spatial factors and architectural and equipment elements, was developed. In Step 3: Development and verification of prediction tool considering economic feasibility, t... [more]

This study is an attempt to suggest a new state system of permafrost monitoring, primarily for energetic infrastructure, based on past approaches and achievements in Russia for over a hundred years of Arctic studies. The methodology of this study is based on general theoretical methods of scientific research. Historical (retrospective analysis of the development of the monitoring system of long-term permafrost in Russia) and logical (inductive generalization) methods were applied. The structure and methods of permafrost monitoring in the Soviet Union and new technologies used nowadays to establish permafrost monitoring systems, taking into account modern Arctic energetic development, have been analyzed.

The cement industry confronts significant challenges in raw materials, energy demands, and CO2 emissions reduction, which are global and local environmental concerns. Life cycle assessment (LCA) has been used in many studies to assess the environmental impact of cement production and investigate ways to improve environmental performance. This study aims to analyse the environmental impact of Portland cement (CEM I) on the South African cement industry using the life cycle impact assessment (LCIA), based on the Recipe 2016 v 1.04 midpoint method. The study was conducted using data modeled after the South African cement plant, considered a cradle-to-gate system boundary, starting from the extraction of the raw material to the cement production process that produces cement as the main product. The data were obtained from the Ecoinvent database v3.7.1, integrated with SimaPro 9.1.1. software, used to assess the impact categories. For simplicity, the study merged the entire production proce... [more]

Sustainable biofuel production is the most effective way to mitigate greenhouse gas emissions associated with fossil fuels while preserving food security and land use. In addition to producing bioenergy, waste biorefineries can be incorporated into the waste management system to solve the future challenges of waste disposal. Biomass waste, on the other hand, is regarded as a low-quality biorefinery feedstock with a wide range of compositions and seasonal variability. In light of these factors, biomass waste presents limitations on the conversion technologies available for value addition, and therefore more research is needed to enhance the profitability of waste biorefineries. Perhaps, to keep waste biorefineries economically and environmentally sustainable, bioprocesses need to be integrated to process a wide range of biomass resources and yield a diverse range of bioenergy products. To achieve optimal integration, the classification of biomass wastes to match the available bioprocess... [more]

Renewable energy has become a crucial factor for circular economies, sustainable development, and the environment given the limited non-renewable energy reserves and global environmental degradation mainly resulting from non-renewable energy use. This study explores the effect of educational attainment and economic growth on renewable energy use in a sample of selected emerging markets over the 2000−2018 period through causality and cointegration analyses. Causality analysis points out a significant unidirectional causality from indicators of educational attainment and economic growth to renewable energy use. In other words, educational attainment indicators and economic growth are significant determinants of renewable energy in the short run. Furthermore, the cointegration analysis ascertains a positive influence of indicators of educational attainment and economic growth on renewable energy use in the long run. The findings of both analyses indicate that educational attainment and ec... [more]

A company’s productivity and success measure its effectiveness. This article presents the problem of economic efficiency and aspects related to environmental protection. The basic parameters analysed were the engine type and how it affects the environment. Over three months, the analysis was carried out and used the data envelopment analysis. As a result of the research carried out, the comparison of the amount of fuel used with the amount of transported goods should answer the following questions: What type of engine should be ordered for new trucks to show the best efficiency during operation? What is the efficiency of the currently used engines? How do they affect the environment? The method proposed in the article makes it possible to define the initial requirements for the definition of truck units, which is included in the conclusions of this paper.

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]