This article presents the results of an eco-efficiency assessment of the application of large-scale rechargeable battery technology in electricity generation from coal. The eco-efficiency of electricity production in a 350 MW coal-fired power plant was calculated. Two production variants were compared: with the use of a lithium-ion battery of a 400 MWh capacity to optimize the operation of power blocks and without using the battery. Hard coal is one of the main fossil fuels used to generate electricity in Poland. Despite the growing share of electricity from renewable sources, this situation will persist for many more years. The main reasons for this are the high costs and long-lasting process of moving away from fossil fuels in the energy sector. Therefore, any technical solutions that can temporarily reduce the negative impact of coal-based power engineering on the environment should be considered. At the same time, the economic aspects of such solutions must be taken into account. T... [more]

In order to assess the merits of national climate change mitigation policies, it is important to have a reasonable benchmark for how much human-caused global warming would occur over the coming century with “Business-As-Usual” (BAU) conditions. However, currently, policymakers are limited to making assessments by comparing the Global Climate Model (GCM) projections of future climate change under various different “scenarios”, none of which are explicitly defined as BAU. Moreover, all of these estimates are ab initio computer model projections, and policymakers do not currently have equivalent empirically derived estimates for comparison. Therefore, estimates of the total future human-caused global warming from the three main greenhouse gases of concern (CO2, CH4, and N2O) up to 2100 are here derived for BAU conditions. A semi-empirical approach is used that allows direct comparisons between GCM-based estimates and empirically derived estimates. If the climate sensitivity to greenhouse... [more]

Energy consumption and pollutant emissions from buildings have caused serious impacts on the environment. Currently, research on building environmental costs is quite insufficient. Based on life cycle inventory of building materials, fossil fuel and electricity power, a calculating model for environmental costs during different stages is presented. A single-objective optimization model is generated by converting environmental impact into environmental cost, with the same unit with direct cost. Two residential buildings, one located in Beijing and another in Xiamen, China, are taken as the case studies and analyzed to test the proposed model. Moreover, data uncertainty and sensitivity analysis of key parameters, including the discount rate and the unit virtual abatement costs of pollutants, are also conducted. The analysis results show that the environmental cost accounts for about 16% of direct cost. The environmental degradation cost accounts for about 70% of the total environmental c... [more]

Carbon dioxide phase transition fracturing has been widely used in rock mass excavation under complex environments, and its special rock breaking process shows obvious gathering energy effect. In this paper, the gathering energy effect of this technology is considered and then the impact reduction coefficient is defined and determined. Eventually, a combined method of field tests and numerical simulations is used to study the crack propagation characteristics and spatiotemporal changes of dynamic response. The results show that the cracks grow more and more slowly as time goes by; the peak displacement and peak point velocity in the primary impact direction are both greater than those in the secondary impact direction. The peak point velocity in different directions decreases as the distance from borehole increases and it decays more and more slowly. With the increase of distance from the borehole, the peak effective stress in the primary impact direction constantly decreases. However,... [more]

The complexity of power systems is rising mainly due to the expansion of renewable energy generation. Due to the enormous variability and uncertainty associated with these types of resources, they require sophisticated planning tools so that they can be used appropriately. In this sense, several tools for the simulation of renewable energy assets have been proposed. However, they are traditionally focused on the simulation of the generation process, leaving the operation of these systems in the background. Conversely, more expert SCADA operators for the management of renewable power plants are required, but their training is not an easy task. SCADA operation is usually complex, due to the wide set of information available. In this sense, simulation or co-simulation tools can clearly help to reduce the learning curve and improve their skills. Therefore, this paper proposes a useful simulator based on a JavaScript engine that can be easily connected to any renewable SCADAs, making it pos... [more]

Sustainable urban transport is fundamental not only for economic growth but also for the environmental protection, thus all logistics activities within the cities should be organized in a way to be environmentally friendly. The article aims at presenting the environmental sustainability of city logistics measures from different stakeholder perspectives. In the paper, a multi-method approach was implemented: literature review, text analysis, text mining, and statistical analysis. The paper presents how the stakeholders perceive urban logistics, if they see the need for coordination of its elements, who should be responsible for it, and what areas are the most important for them. The main task of this study is to recognize the priorities of different stakeholders. In consequence, the final effect of this article is an insight that is valuable not only for the local authorities but for many stakeholders, groups operating within the city that are and in many cases cooperating within the fr... [more]

The paper presents a review of the geological and hydrogeological data of the Lower Cretaceous aquifer in the Polish Lowlands and discusses the possibilities for the utilisation of geothermal water resources in existing and new district heating systems. Based on experience related to the use of thermal waters in existing geothermal systems, and using data from the literature, assessments have been made of the energy and environmental effects of the application of low-enthalpy geothermal resources from the Lower Cretaceous aquifer as a source of heat for urban district heating systems. The authors concluded that the implementation of such solutions could result in the production of approximately 4 PJ of geothermal energy annually. To date, these resources have only been developed in three locations—Mszczonów, Uniejów and Poddębice—with the total amount of energy generated annually reaching 100 TJ/year. Similar district heating networks in 120 nearby localities have been also identified.... [more]

Farming systems need to be planned to provide suitable levels of economic profitability and, at the same time, ensure an effective energy use, in order to perform environmentally friendly production strategies. The herein present work aims to assess the efficiency of energy use and economic impacts of the main farming methods (conventional, organic and integrated) of Clementine’s crops in Calabria (South Italy), through a combined use of Life Cycle Energy Assessment (LCEA) approach and economic analysis. For this purpose, data were collected from clementine producers by using face-to-face interviews. The results revealed that average energy consumption in the organic farming systems was 72,739 MJ, lower than conventional and integrated systems equal to 95,848 MJ and 94,060 MJ, respectively. This is mainly due to the ban of chemicals. Economic analysis showed that organic farms were more profitable compared with the other farming methods, because of the greater selling price and the EU... [more]

The paper presents the results of a study on chemical composition of ashes from three types of waste biomass in terms of fertilizer usefulness. Waste from the process of corn grain drying, including corn cobs, corn grains and corn husk and their mixtures in the ratio 4:1 (v/v) were examined. The study proved that corn grain was the material with the highest concentration of macroelements among those studied (P—21,452 ppm, K—25,970 ppm, S—5911 ppm) and the mixture of corn cobs with corn grains (Ca—81,521 ppm). When microelements were considered, the highest concentration was recorded for corn cobs (Cu—207 ppm, Mn—844 ppm, Zn—857 ppm) and corn husk (Fe—15,100 ppm). The analysis of toxic elements in the ashes of the biomass studied showed their highest concentration in corn husk ash (Ni—494 ppm, Cr—301 ppm, Pb—42.7 ppm, As—4.62 ppm). The analysis showed that regardless of the type of biomass studied, all ashes were strongly enriched (in relation to the average soil content) with phosphoru... [more]

Neighboring stand-alone hybrid microgrids with diesel generators (DGs) as well as grid-feeding photovoltaics (PV) and grid-forming battery storage systems (BSS) can be coupled to reduce fuel costs and emissions as well as to enhance the security of supply. In contrast to the research in control and small-signal rotor angle stability of microgrids, there is a significant lack of knowledge regarding the transient stability of off-grid hybrid microgrids in a cluster environment. Therefore, the large-signal rotor angle stability of pooled microgrids was assessed qualitatively and also quantitatively in this research work. Quantitative transient stability assessment (TSA) was carried out with the help of the—recently developed and validated—micro-hybrid method by combining time-domain simulations and transient energy function analyses. For this purpose, three realistic dynamic microgrids were modelled regarding three operating modes (island, interconnection, and cluster) as well as the conv... [more]

Decarbonization of energy-intensive systems (e.g., heat and power generation, iron, and steel production, petrochemical processes, cement production, etc.) is an important task for the development of a low carbon economy. In this respect, carbon capture technologies will play an important role in the decarbonization of fossil-based industrial processes. The most significant techno-economic and environmental performance indicators of various fossil-based industrial applications decarbonized by two reactive gas-liquid (chemical scrubbing) and gas-solid CO2 capture systems are calculated, compared, and discussed in the present work. As decarbonization technologies, the gas-liquid chemical absorption and more innovative calcium looping systems were employed. The integrated assessment uses various elements, e.g., conceptual design of decarbonized plants, computer-aided tools for process design and integration, evaluation of main plant performance indexes based on industrial and simulation r... [more]

Globally, the use of electric vehicles, and in particular the use of electric buses, has been increasing. The city of Nanjing leads China in the adoption of electric buses, supported by city policies and infrastructure. To lower costs and provide a better service, vehicle selection is crucial, however, existing selection methods are limited. Accordingly, Nanjing Bus Company developed a test method based on road tests to select a bus. This paper presents a detailed description of the test method and a case study of its application. The method included an organization structure, selection of eight test vehicles (four 10 m length, four 8 m length) from four brands (a total of 32 test vehicles), selection of indicators and selection of routes. Data was collected from repeated drives by 65 drivers over an 8-week period. Indicators included power consumption, charging duration, failure duration and driving distance. It is concluded that the road test method designed and conducted by the Nanj... [more]

The production cost of greenhouse cultivation depends mainly upon significant amounts of energy consumption in order to keep the optimum environmental condition for plant growth. Τhe expenditure on energy, either for heating or cooling, ranges between 30% to 60% of the total production costs, and any attempt to save energy will result in a positive effect on the potentiality of production accordingly, affecting the greenhouse product prices. Research has shown that CO2 enrichment in greenhouses significantly increases the yield of most indoor cultivation of plants of the C3 category. For these plants, when the CO2 concentration increases by three times above that of the atmosphere (380 ppm), the optimum plant growth temperature shifts higher by 5 °C to 10 °C reaching up to 30 °C to 32 °C. Therefore, huge amounts of solar energy can be captured inside the greenhouses, as the ventilation can be decreased. Alongside this, the use of a simple passive solar system consisting of plastic slee... [more]

The article presents the results of a study aiming to select the optimal source of heat for a newly designed single-family home. Commercial software was used to compare heating and ventilation systems involving a bituminous coal boiler, a condensing gas boiler, a biomass boiler, a heat pump with water and glycol as heat transfer media. The effectiveness of natural ventilation, mechanical ventilation with a ground-coupled heat exchanger, and solar heater panels for water heating were evaluated. The analysis was based on the annual demand for useful energy, final energy, and non-renewable primary energy in view of the pollution output of the evaluated heating systems. The analysis revealed that the heat pump with water and glycol was the optimal solution. However, the performance of the heat pump in real-life conditions was below its maximum theoretical efficiency. The biomass boiler contributed to the highest reduction in pollutant emissions (according to Intergovernmental Panel on Clim... [more]

Heat is usually transported by hydraulic circuits where the working medium is circulated by an electric pump. Heat can also be transferred by natural convection in passive systems. Passive systems where heat is transported downward have also been described and studied in the literature. These types of devices are referred to as reverse thermosiphons. However, systems of the type are not widely applied in practice due to the problems associated with the selection of the optimal working medium. In water-based thermosiphons, negative pressure is produced when water temperature falls below 100 °C, and non-condensable gas can enter the system. These problems are not encountered in systems where the working medium has a low boiling point. However, liquids with a low boiling point can be explosive, expensive, and harmful to the environment. The solution proposed in this paper combines the advantages of water and a liquid with a low boiling point. The described system relies on water as the he... [more]

The use of forest biomass for bioenergy in Australia represents only 1% of total energy production but is being recognized for having the potential to deliver low-cost and low-emission, renewable energy solutions. This review addresses the potential of forest biomass for bioenergy production in Australia relative to the amount of biomass energy measures available for production, harvest and transport, conversion, distribution and emission. Thirty-Five Australian studies on forest biomass for bioenergy are reviewed and categorized under five hierarchical terms delimiting the level of assessment on the biomass potential. Most of these studies assess the amount of biomass at a production level using measures such as the allometric volume equation and form factor assumptions linked to forest inventory data or applied in-field weighing of samples to predict the theoretical potential of forest biomass across an area or region. However, when estimating the potential of forest biomass for bioe... [more]

With the gradual increasing of the transmission voltage level, the situation of interference on secondary side equipment in smart substations is becoming more serious. The authors tested the interference waveforms caused by the circuit breaker’s operation at the smart substation, which showed the severity of the electromagnetic (EM) environment. This paper takes the electronic current transformer acquisition card as an example. The influence of EM interference sources on the reliability of the acquisition card is analyzed. Then, standardized electromagnetic compatibility (EMC) immunity tests of the international electrotechnical commission (IEC) for different interferences are implemented. Typical output characteristics of acquisition cards for different tests are analyzed. Innovatively, this paper proposes a quantitative evaluation method of output waveform disturbance to evaluate the acquisition card’s performance. This disturbance distortion is of great significance to the EM enviro... [more]

Heat damage in deep mines is severe and can lead to adverse health effects. The existing refrigeration schemes for the heading face in excavation roadways aim to cool the whole cooling region. However, the ratio of the area occupied by workers to that of the cooling region is quite small. A great quantity of energy for refrigeration is doomed to waste. In this study, a new cooling strategy for building a non-uniform environment in the heading face was developed. A certain quantity of well-designed tracking air coolers were distributed in the excavation roadway near the heading face. The air cooler tracked the constantly moving workers and blew cold air to them. Economic analysis based on estimation of the cooling load for this cooling strategy was conducted. The airflow in the excavation roadway was numerically simulated to estimate the cooling effect. An average energy saving of approximately 30% could be realized. The thermal environment for the workers whether near the heading face... [more]

An increase in demand for energy natural resources has stimulated the development of gas pipeline networks in Europe, as well as globally. Also, in Poland in recent years there has been a significant increase in natural gas consumption. Therefore, it is necessary to build new pipelines networks using dig and no−dig techniques. Horizontal Directional Drilling is one of the most popular trenchless technologies. The aim of this article is to present a new approach in the design of HDD trajectories in two−dimensional space (2D). A review of the trajectories used so far has been provided, offering calculation algorithms to determine their well path. Then, the original catenary method is proposed, taking into account natural deflection of casing pipes. Applicable formulas and computational algorithms have been given, together with a computational example which enables comparison of the classical design methodology with the new one. According to the authors, due to natural stress distribution... [more]

Solar radiation is the sole energy source for Chinese solar greenhouse agriculture. A favorable light environment is the foundation of a desirable crop growth environment, and it is key in solar greenhouse design. In this study, a mathematical model is established to quantitatively evaluate the solar greenhouse light environment. The model was developed considering the greenhouse shape parameters, materials’ optical properties, and interior solar radiation evolution, including the beam radiation, diffuse radiation, and multi-reflection. The model was validated under different weather conditions, and the results reveal a mean percentage error of 1.67 and 10.30% for clear sunny weather and cloudy weather, respectively, and a determination coefficient of 0.9756. By using this model, the solar radiation allocation in a solar greenhouse was calculated to determine the solar radiation availability for the heat-storage north wall and the entire greenhouse, and the dynamical spatial distributi... [more]

Advanced thermal control technologies have been continuously developed to complement conventional models and algorithms to improve their performance regarding control accuracy and energy efficiency. This study analyses the strengths and weaknesses of simultaneous controls for the amount of air and its temperature by use of on-demand and predictive control strategies responding to two different outdoor conditions. The framework performs the comparative analyses of an on-demand model, which reacts immediately to indoor conditions, and a predictive model, which provides reference signals derived from data learned. Two models are combined to make a comparison of how much more efficient the combined model operates than each model when abnormal situations occur. As a result, when the two models are combined, its efficiency improves from 20.0% to 33.6% for indoor thermal dissatisfaction and from 13.0% to 44.5% for energy use, respectively. This result implies that in addition to creating new... [more]

The effective thermal conductivity (λeff) of sands is a critical parameter required by applications in geothermal energy resources, geo-technique and geo-environment and in science disciplines. However, the availability of the reliable λeff data is not sufficient and predictive models are usually used in practice to estimate λeff. These predictive models may vary in complexity, flexibility, accuracy and applications. There is no universal model that can be applied to all soil types and full water content range. The choice of different models may result in distinctive estimates of λeff. The objectives of this study were to conduct an extensive review of the thermal conductivity models of sands and evaluate their performance with a large dataset consisting of various sand types from dry to saturation. A total of 14 models to predict λeff of sands were evaluated with a large compiled dataset consisting of 1025 measurements on 62 sands from 20 studies. The results show that the models of C... [more]

Multi-fractured horizontal wells (MFHW) is one of the most effective technologies to develop tight gas reservoirs. The gas seepage from tight formations in MFHW can be divided into three stages: early stage with high productivity, transitional stage with declined productivity, and final stage with stable productivity. Considering the characteristics and mechanisms of porous flows in different regions and at different stages, we derive three coupled equations, namely the equations of porous flow from matrix to fracture, from fracture to near wellbore region, and from new wellbore region to wellbore then an unstable productivity prediction model for a MFHW in a tight gas reservoir is well established. Then, the reliability of this new model, which considers the multi-fracture interference, is verified using a commercial simulator (CMG). Finally, using this transient productivity prediction model, the sensitivity of horizontal well’s productivity to several relevant factors is analyzed. T... [more]

Oily brine from the gas and oil industries remains the most difficult wastewater to treat due to its complex chemical composition, which includes aromatic hydrocarbons. Even at low concentrations, the presence of BTX (benzene, toluene, xylenes) can be extremely harmful to aquatic ecosystems. Fixed-bed adsorption columns are recommended for oily water treatment due to their flexibility and easy operation. In this research, pine sawdust modified with polydimethysiloxane (PDMS) and hydrophobic nanosilica was applied as a sorbent in a filtration system. The surface modification of raw fiber allowed to change its morphology and increase the roughness of it. The Yoon−Nelson, Bohart−Adams, Clark, and Belter models were applied to simulate continuous biosorption. The Bohart−Adams model strongly correlated with the experimental data and described the whole dynamic behavior of the column. The effect of feed flow rate (10−50 mL/min) on breakthrough characteristics was determined. Both the breakth... [more]

The rapid development of automobile industry in China did improve people’s quality of life. However, it has also damaged the ecological environment. The emission of a large amount of automobiles is one of the serious air pollution sources. In recent years, the shortage of petrochemical energy, the rapid rise of harmful particles in the air (e.g., PM2.5 and PM10), and the increasing worse atmospheric environment are becoming obstacles to China’s sustainable development. Battery electric vehicles (BEVs) are recognized as an ideal alternative to conventional cars. This study aims to explore the factors that can promote consumers’ adoption of BEVs and to construct domains of these factors. Firstly, an open web questionnaire and semi-structured interviews were conducted to widely collect factors that promote consumers’ purchase of BEVs. Then, questionnaire survey and exploratory factor analysis were used to construct domains of promoting consumers’ purchasing willingness. A total of six fac... [more]