Coal-fired power plants have been identified as one of the major sources of air pollutants in the power sector. Most coal-fired power stations have large open-air coal stockpiles, which lead to a considerable amount of fugitive dust. The construction of an indoor coal storage is known to control coal dust; however, it requires significant upfront capital. Certain power utilities, including those in South Korea, are currently considering or are required to build indoor coal storages. This study analyzed the benefit and economic feasibility of indoor coal storages in coal-fired power stations. A contingent valuation method was used to elicit people’s willingness to pay for the construction of new indoor coal storages. The results showed that, on average, a South Korean household was willing to pay KRW 59,242 (USD 53.97) in a lump-sum payment toward the construction of indoor coal storages at six coal-fired power stations (total storage capacity of 5.47 million tons of coal, with a site a... [more]

Interest in biomass has increased due to current environmental issues, and biomass analysis is usually performed using element and proximate analyses to ascertain its fuel characteristics. Mainly, element component prediction models have been developed based on proximate analysis, yet few studies have predicted proximate components based on element analysis. Hence, this study developed a proximate component prediction model following the calorific value calculation. Analysis of Pearson’s correlation coefficient showed that volatile matter (VM) and fixed carbon (FC) were positively correlated with hydrogen and oxygen, and with carbon, respectively. Thus, the model correlation was developed using a combination of the “stepwise” and “enter” methods along with linear or nonlinear regressions. The optimal models were developed for VM and ash content (Ash). The VM optimal model values were: R2 = 0.9402, root-mean-square error (RMSE) = 7.0063, average absolute error (AAE) = 14.8170%, and aver... [more]

The Italian National Recovery and Resilience Plan (NRRP) includes, among other measures, investments in hydrogen vehicle refuelling stations, intending to promote the use of fuel cell electric vehicles (FCEVs) for long-haul freight transport. This paper evaluates the impact that this action could have on CO2 emissions and fuel consumption, focusing on a case study of the Campania region. The proposed approach, which can also be transferred to other geographical contexts, requires the implementation of a freight road transport simulation model; this model is based on the construction of a supply model, the estimation of road freight demand, and an assignment procedure for computing traffic flows. This study covers the period from 2025 to 2040, according to the forecasts of the NRRP and some assumptions on the action effects; moreover, it is assumed that hydrogen is entirely produced from renewable sources (green hydrogen). The key findings from three different scenarios show that saving... [more]

The sources and sinks of dissolved CH4 in offshore waters are becoming diversified with the rapid increase in human activities. The concentration and air−sea exchange flux of dissolved CH4 present new characteristics of more intense spatiotemporal evolution, and the contribution to atmospheric CH4 continues to increase. Herein, a new model based on navigable air−sea exchange flux observations was proposed, which replaced the traditional station-based sampling analysis and testing method, realizing the synchronous measurement of methane in the atmosphere and surface seawater carried by ships. Based on the Marine Geological Survey project of the China Geological Survey, comprehensive environmental surveys were conducted in April 2018, September 2018, and June 2019 in the Qiongdongnan area in the northern part of the South China Sea, and the dissolved methane content in the sea surface atmosphere and surface seawaters in 2019 were simultaneously obtained. The methane exchange flux ranges... [more]

The limited use of non-renewable energy sources facilitates a reduction in the negative environmental impact of electricity production. The policies of European countries aim to change the structure of electricity sources, focusing particularly on non-renewable sources. The aim of this study was to assess changes in the structure of electricity generation depending on the energy sources used in 34 European countries in the years 1990−2020 in terms of their environmental impact. This study was conducted using cluster analysis: a method applied in multivariate comparative analyses. Such an approach provided a new, broader outlook on changes in the structure of electric energy production in Europe. A total of nine homogeneous groups of countries were distinguished in terms of energy transformation. The ecological scarcity method 2013 was applied to assess the environmental impact of electricity production in the analyzed countries. In the investigated period, the negative environmental im... [more]

Algae are a diverse group of aquatic organisms and have a potential to produce renewable biofuel via hydrothermal liquefaction (HTL). This study investigated the effects of reaction environments on biocrude production from “Tetraselmis sp.” algae strain by HTL process using red mud (RM) based catalyst. The inert (N2), ethylene (C2H4), reducing (10% H2/90% N2), and oxidizing (10% O2/90% N2) environments were applied to the non-catalytic as well as catalytic HTL treatments with two forms of RM catalysts: RM reduced at 500 °C (RRM) and nickel-supported RM (Ni/RM). Under nitrogen, ethylene and reducing environments, the biocrude yield increased by the following trend: No Catalyst < RRM < Ni/RM. The Ni/RM catalyst produced the highest biocrude yield (37 wt.%) in an ethylene environment, generated the lowest total acid number (14 mg KOH/g) under inert atmosphere, and lowered sulfur (33−66%) and oxygen (18−30%) from biocrude products irrespective of environments. The RRM catalyst maximi... [more]

The growing environmental problems associated with the dumping of large amounts of textile waste and the demand for circular products are prompting textile waste recycling enterprises to develop circular business models (CBMs). This implies a radical change in the way some enterprises operate to obtain growth. Considering the importance of the drivers of and barriers for the adoption and implementation of CBMs in the textile recycling sector, it is claimed that the comprehension of these factors to CBMs is limited and deserves more attention in empirical research. Therefore, our research investigates the antecedents of circular business models in the textile recycling sector by highlighting influencing factors. The aim of the article is to explore the main enhancing and inhibiting factors in the development of circular business models on the example of a large enterprise operating for 30 years in the textile recycling sector. In this study, a case study design of mixed methods, includi... [more]

The development and implementation of public policies towards renewable energies are crucial in order to address the contemporary challenges faced by humanity. The 3Rs (reduce, reuse, and recycle), as a circular economic practice, are often cited as one of the best solutions for sustainable development. Therefore, this study analyzed public policies for renewable energy from the perspective of the circular economy. Accordingly, a systematic review of the literature was carried out with respect to the beneficiaries and convergences of circularities, with a focus on public policies for renewable energies. The sample had public policies classified into three types (distributive, redistributive, and regulatory policies). The results showed that the first studies began in 1999, with a significant increase in publications during the 2010s, in which Germany was the country with the greatest contribution. The analyses associated with space showed the countries committed to the use of renewable... [more]

The disruption of fossil fuel supply chains due to the war in Ukraine has resulted in the need for an urgent reorganisation of the energy supply system, the cost of which has created a substantial increase in electricity prices in many markets. In light of the above, the need for the development of a renewable energy market has become stronger than ever; hence, the authors of this study have oriented their efforts towards investigating the development of the renewable energy market in countries bordering the line of armed conflict in Ukraine, i.e., Poland—strongly dependent on traditional forms of energy production—and Lithuania. The primary objective of the paper is to review the literature on wind energy, which is necessary to establish the current role of this energy dimension in the renewable energy market in the energy systems of Poland and Lithuania. Therefore, this review paper is oriented towards a review and evaluation of the available thematic literature and industry studies,... [more]

Methane from environmentally friendly anaerobic digestion may be an alternative non-renewable source that is depleting. One of the substrates for that process may be lignocellulose-based materials. The article concerns comparing the environmental impact as well as technical and energy indicators of alternative ways of producing methane from the anaerobic digestion of Pennisetum hybrid. Five scenarios were analyzed: methane production from the anaerobic digestion of the raw grass, the grass subjected to alkaline pretreatment (with 2% NaOH solution at two temperatures), and the grass subjected to mechanical pretreatment (ground to obtain particle sizes <0.18 mm and 0.25−0.38 mm). Multi-criteria decision (MCA) analysis was carried out with the use of five indicators, including life cycle assessment results as well as methane production parameters, in order to optimize this sustainable way of bioenergy production. The purpose of this study was to identify the most cost-effective and env... [more]

A smart grid (SG), considered as a future electricity grid, utilizes bidirectional electricity and information flow to establish automated and widely distributed power generation. The SG provides a delivery network that has distributed energy sources, real-time asset monitoring, increased power quality, increased stability and reliability, and two-way information sharing. Furthermore, SG provides many advantages, such as demand response, distribution automation, optimized use of electricity, economical energy, real-time grid status monitoring, voltage regulation or VAR control, and electricity storage. In this survey, we explore the literature on smart Grid enabling technologies until 2022. We dig out four major systems: (1) the smart grid’s prominent features and challenges; (2) the smart grid standard system and legislations; (3) smart grid energy subsystem; and (4) the smart grid management system and protection system for new researchers for their future projects. The research chal... [more]

In this study, renewable and sustainable biofuel production from waste cooking oil and its blends with diesel fuel are investigated in terms of specific fuel properties. The fuel blends are named “Renewable Biofuel (RBF) 20” (20% biofuel−80% diesel), “Renewable Biofuel 50” (50% biofuel−50% diesel), and “Renewable Biofuel 100” (100% biofuel). The acid number, flash point, viscosity, cloud point, density, and pour point fuel properties of the new Renewable Biofuels are experimentally obtained and compared with diesel fuel. The viscosities of the biofuels are found to be 2.774 mm2/s for Renewable Biofuel 20, 3.091 mm2/s for Renewable Biofuel 50, and 4.540 mm2/s for Renewable Biofuel 100. Renewable Biofuel 20 has the minimum density value among biofuels. The density of Renewable Biofuel 20, Renewable Biofuel 50, and Renewable Biofuel 100 are obtained as 835 kg/m3, 846 kg/m3, and 884 kg/m3, respectively. More energy can be released with the use of Renewable Biofuel 100 in terms of heating v... [more]

The proper development of transportation constitutes the basis for an effectively functioning economy at the national and global levels. On the other hand, transportation significantly impacts the environment and climate. Sustainable transportation management should therefore include both economic, social and environmental aspects. The article aims to comprehensively assess the economic−energy−environmental efficiency of the 27-road freight transport sector in EU countries in 2019. The research was conducted using the non-parametric Data Envelopment Analysis (DEA) method. The Slacks-Based Measure−Data Envelopment Analysis (SBM-DEA) model was used, taking into account unwanted (undesirable) effects. As non-energy inputs in the DEA model used the labor in the road freight transport sector, stock of registered goods vehicles, and the length of the road network. Moreover, the energy consumption by the road freight transport sector was used as energy inputs in the DEA model. Desirable outpu... [more]

This study aims to create a comprehensive, holistic approach to evaluate the environmental, energy, and economic impacts of air source heat pump deployment scenarios through: (i) a life cycle assessment of air source heat pumps in Orkney houses, (ii) energy systems optimisation modelling to optimise the performance of an air source heat pump coupled with thermal energy storage tank to reduce use phase related impacts in Orkney, (iii) modelling of Orkney’s domestic building stock to understand the housing condition, and (iv) economic modelling to analyse the life cycle cost of an air source heat pump and potential savings when replacing conventional heating systems. The results show that an 82% reduction in energy supply could be achieved when ambitious energy efficiency improvement measures are adopted in the circular economy scenario. The use phase related emissions could be reduced by 98% when the air source heat pump becomes the only heating technology in Orkney. However, the life c... [more]

Biochar, known as “Black Gold”, has become a novel approach with potential benefits for soil amendment, such as improving soil physicochemical properties, reducing greenhouse gas emissions, and enhancing soil fertility. The previous research studies mainly focus on exploring different methods for the improvement of biochar enriched nutrients as fertilizers; however, the migration and transformation mechanisms of these nutrients induced by biochar are yet to be extensively investigated. This paper provides an overview of recent advances in the application and mechanisms of biochar for soil amendment focusing on soil properties and nutrients improvement. Biochar positively alters microbial-mediated reactions in the soil C and N cycles, i.e., mineralization of C and N, and N2 fixation, thus enhancing maximizing C and N use efficiency and reducing the potential losses. Moreover, biochar provides reactive surfaces where P and K ions are retained in soil microbial biomass and in exchange sit... [more]

Wind energy conversion systems (WECSs) are considered green generators, environmentally friendly, and fully suitable energy sources to replace fossil energy sources. WECS’s output power is hugely dependent on the random nature of the wind. There are many solutions to improve the output power for WECSs, such as adjusting the profile of turbine blades, locating installation places, improving generators, etc. Nevertheless, maximum power point tracking (MPPT) algorithms for WECSs are optimal and the most effective because they are flexible in controlling different variable wind speeds and match all types of WECS. The parameters on the generator side control or the grid side control will be adjusted when MPPT algorithms are used, allowing the output power of WECSs to be maximized while maintaining stability in variable-speed wind. There are various MPPT algorithms, but the current problem is their efficiency and whether it requires deep knowledge to select the best MPPT solutions because ea... [more]

The gasification of Polish coal to produce hydrogen could help to make the country independent of oil and gas imports and assist in the rational energy transition from gray to green hydrogen. When taking strategic economic or legislative decisions, one should be guided not only by the level of CO2 emissions from the production process, but also by other environmental impact factors obtained from comprehensive environmental analyses. This paper presents an analysis of the life cycle of hydrogen by coal gasification and its application in a vehicle powered by FCEV cells. All the main stages of hydrogen fuel production by Shell technology, as well as hydrogen compression and transport to the distribution point, are included in the analyses. In total, two fuel production scenarios were considered: with and without sequestration of the carbon dioxide captured in the process. Life cycle analysis was performed according to the procedures and assumptions proposed in the FC-Hy Guide, Guidance D... [more]

Biochar (BC) is a material that has many applications in agricultural and environmental activities. The aim of the study was to define the influence of BC produced in low-temperature pyrolysis from various organic waste materials, including one-month-old compost (OMOC), pine bark (PB), pine needle mulch (NM), pine cones (PC) and maple leaves (ML), on soil enzyme activity as well as its relation with organic matter properties. A 60-day incubation pot experiment was set up to investigate the influence of BC amendment on soil (S) characteristics. After incubation, we investigated the activity of soil enzymes, the content of available phosphorus (AP), potassium (AK) and magnesium (AMg), total organic carbon (TOC), total nitrogen (TN), dissolved organic matter (DOM) and its fractional composition (content and share of carbon and nitrogen of humic (CHAs, NHAs) and fulvic (CFAs, NFAs) acids and humin fractions). The effect of the amended biochars differed depending on the feedstock material.... [more]

(1) Background: The embodied energy of building materials is a significant contributor to climate change, in tandem with the energy use intensity (EUI). Yet, studies on the material impacts of European retail buildings, namely with relation to EUI, are missing. Hence, this study set out to: (i) evaluate the embodied energy and carbon emissions for a European retail building; (ii) quantify the material flow in terms of mass; (iii) compare the embodied aspects to the operational EUI and carbon use intensity (CUI); (iv) assess building materials with higher impacts; and (v) investigate strategies to mitigate materials’ impacts. (2) Methods: A Portuguese retail building was selected as a case study. A simplified LCA method was followed (cradle-to-gate), analysing the shell building materials in terms of primary energy demand and global warming potential. (3) Results: the embodied energy represented 32% of total lifecycle energy while the embodied carbon represented 94%. EUI was 1×kWh/m2/y... [more]

As increasing soil organic matter is considered one of the main strategies for reducing desertification in Europe, the production and use of high-quality composts has gained importance during the last decade. It is undisputed that the quantity and quality of humic substances (HS) and their fractions, i.e. fulvic acids (FA) and humic acids (HA) in compost are considered important indicators of compost maturity and chemical stability. Other important aspects are concentrations of macro- and micronutrients and heavy metals (HMs) that are introduced to the soil with mature compost. In this light, this study assessed the detailed characteristic of compost from municipal sewage sludge. Moreover, kinetic of organic matter (OM), and nitrogen transformations, therein nitrogen loss, were analysed. OM degradation proceeded according to first-order kinetics. In the bioreactor, the rate constant of OM removal and the rate of OM removal were 0.134 d−1 and 12.6 mg/(g d.m.d), respectively. In the wind... [more]

The study of extraordinarily high organic matter content (EHOMC) is beneficial to promote the fine evaluation of shale oil and gas, but so far, there have been few studies on its mechanism. This paper carried out a comprehensive lithological and geochemical analysis of the black shales of the Wujiaping Formation in the Kaijiang-Liangping Trough. The results showed that the black shales of the Wujiaping Formation can be divided into two units (the upper and lower parts), and EHOMC occurs in its upper part. The redox-sensitive trace elements (RSTEs), MoEF-UEF covariation, and Ni/Co correlation showed that the lower part of Wujiaping Formation was a weakly restricted oxidation environment, while the upper part evolved into a sulfidation reducing environment. The productivity indicator elements (BaXS, NiXS, CuXS, P, and Mo) indicated that the upper Wujiaping Formation had higher primary productivity than the lower part. However, rare earth elements ((La/Yb)N) indicated that the deposition... [more]

The presence of a high concentration of Cl− in saltwater will erode the structure and facilities, reducing the stability and service life of the underground oil storage cavern. In order to reduce the risk of seawater intrusion, this paper studies the risk and prevention technology of seawater intrusion based on a case study of a coastal and large-span underground oil storage cavern. A refined three-dimensional hydrogeological model that comprehensively considers permeability coefficient partitions, faults, and fractured zones are constructed. The seepage fields and seawater intrusion risks of the reservoir site in its natural state, during construction, and during operation are examined, respectively. The study quantifies the water inflow and optimizes the seawater intrusion prevention technology. The results indicate that there is no risk of seawater incursion into the cavern under natural conditions. The water inflows after excavating the top, middle, and bottom sections of the main... [more]

The marine environment in which offshore wind turbines are located is very complex and subjected to a variety of random loads that vary with time and space. As an important component of offshore wind power, the cable also bears the impact of the environment in which most of the turbines are located. Under the long-term action of mechanical stresses such as tension, torsion, and vibration, the cable insulation will crack due to stress fatigue leading to partial discharge, which seriously affects its electrical performance. The study of the mechanism of the change of electrical properties of cable insulation due to mechanical behavior is of great theoretical guidance to improve the reliable operation of cables. This paper first introduces the basic characteristics and operating conditions of torsion-resistant cables and submarine cables. Then the mechanical behavior of the cables is summarized, and the deterioration mechanism and deterioration effect of wind power cable insulation under... [more]

Sichuan is gradually being transformed and is utilizing groundwater and thermal resources. However, this investigation found that the high mineralization rate of geothermal resources in the Sichuan Basin is common and efficient, and environmentally friendly descaling technology is the key to promoting the utilization of thermal resources in low-yield oil and gas wells. Due to the high efficiency, low cost, and lack of pollution of high-pressure jet descaling, it has attracted more and more attention recently, but the mechanism of jet descaling is still unclear. The key to jet descaling is the stress concentration in the scale caused by the impact of droplets from the jet. In this paper, the process of jet descaling is simplified as a 2D droplet−scale collision with a detailed theoretical analysis of the stress on the scale. A circular droplet was simulated to impact the surface of the scale. By using numerical methods for transient calculations, we couple the pressure of the droplets a... [more]

Affordable and clean energy for any rural community is crucial for the sustainable development of the community and the nation at large. The utilization of diesel-based power generation is one of the barriers to the sustainable development of these communities. Such generations require fuel that has a volatile market price and emits massive greenhouse gas emissions. This paper presents the design, modeling, and simulation of a hybrid power system for a rural area in the Sultanate of Oman that aims to reduce daily consumption of diesel fuel and greenhouse gas emissions. Hybrid Optimization of Multiple Energy Resources (HOMER) is utilized to model multiple energy mix hybrid systems and to propose the best optimal energy mix system for a selected community. In addition, Electrical Transient Analyzer Program (ETAP) software is employed to assess hybrid system operational performances, such as bus voltage profiles and active and reactive power losses. This study revealed that the PV−wind−di... [more]