The article proposes methods for determining the optimal thermal insulation thickness for economic and ecological reasons, depending on the number of degree days of the heating period. Life cycle assessment was used for the ecological analysis. Analyses were performed for selected variants typical of Polish conditions. The optimal thermal insulation thickness as well as the amount of economic and ecological benefits depends very much on the condition of the building without thermal insulation, but also on the heat source used and the thermal insulation material to be used. For each variant, the optimal thermal insulation thickness for ecological reasons is much greater than the optimal for economic reasons. Taking into consideration the climatic zone and the associated number of degree days of the heating period, the colder the zone, the greater the optimal insulation thickness, as well as economic and ecological benefits.

In this paper, various modern power engines developed by the American, Japanese, and European automobile industries will be compared. Specific data, including the efficiency, emission rate of nitrogen oxides (NOx), fuel consumption, and electronic vehicle technology, will be developed. Since the first invention of the automobile engine in the late 19th century, companies came up with unique innovations, including its structure, control systems, and additional mechanical installations to improve efficiency and reduce emissions. Numerous companies, including Ford, Toyota, and Mercedes-Benz, compete in the automobile industry to improve their engine’s efficiency and emission rates to create a clean environment. In addition, each country has its regulations on emission rates and automobile structure. Therefore, to meet these regulations, the structure and the system of the engines vary between companies in different countries. A variety of variable valve timing (VVT) systems, which is a me... [more]

The environmental safety of a car is currently one of the most important indicators of vehicle competitiveness and quality in the consumer market. Currently, assessment of the ecological properties of vehicles is based on various criteria. In the case of combustion-powered cars, most attention is usually paid to the values characterizing their use, and in terms of environmental assessment, pollutant emissions, and operational fuel consumption are key factors. The current article considers the possibility of using the life cycle assessment (LCA) method to analyze the ecological properties of a passenger car during its operation. A simplified LCA method for vehicles, which, in strictly defined cases, can be used for the analysis of environmental impact and assessment of the energy analysis related to its operation, is presented. For this purpose, a vehicle life cycle model is developed. Data on the operation of 33 passenger cars from different manufacturers with similar operational chara... [more]

The production of wood pellets has grown considerably in the last decades. Besides woody biomass, other feedstocks can be used for pellet production. Among these, miscanthus presents some advantages because, even if specifically cultivated, it requires low inputs such as fertilisers and pesticides and shows high biomass yield (up to 28 tons of dry matter ha−1 in Europe). Even if in the last years some studies evaluated the environmental impact of woody pellet production, there is no information about the environmental performances of miscanthus pellet production. In this study, the environmental impact of miscanthus pellet was evaluated using the Life Cycle Assessment approach with a cradle-to plant gate perspective. Primary data were collected in a small-medium size pelletizing plant located in Northern Italy where miscanthus is cultivated to be directly processed. The results highlight how the miscanthus pellet shows lower environmental impact compared to woody pellet, mainly due to... [more]

Due to the constant evolution of the electricity markets around the world, new possibilities for contracting electricity are emerging. In Brazil, there are two models available to the consumer: the regulated contracting environment and the free contracting environment. Because of these possibilities for contracting electricity, it is important that consumers know how to migrate from the regulated to the free environment when it is an advantage. This study was conducted following the premises of three techniques: systematic literature review, gray literature review, and expert panel. The following question was asked: What are the determining factors to be considered by the consumer at the moment decision to migrate from the regulated electricity market to the free market? In total, 7 factors were identified and discussed in the literature review. The experts who participated in the study pointed out 3 influential scenarios in this decision making to migrate. The main contribution of thi... [more]

Comprehensive evaluation of shale gas resource, which plays a role in energy system optimization, atmospheric environmental cobenefit, and methane risk, has long been ignored in China. This research aims to fill this gap and conduct a study based on the China-Multi-pollutant Abatement Planning and Long-term benefit Evaluation model to answer the research question, “When considering environmental and climate risks, does the shale gas resource in China exert a negative or positive effect?” Results show that shale gas plays an important role in replacing coal and optimizing the energy structure. Shale gas can also effectively help reduce the key local pollutant emissions. Approximately 84.85 thousand of deaths (persons) and 32.24 billion yuan of economic loss can be avoided in 2030 with the reduction of SO2 and NOx. The methane risk, which has been disregarded in China when evaluating cobenefits, is also considered in this study. The economic loss due to methane leakage is estimated to re... [more]

Desalination using fossil fuels is so far the most common technique for freshwater production worldwide. However, such a technique faces some challenges due to limited fossil fuels, high pollutants in our globe, and its high energy demand. In this study, solutions for such challenges were proposed and investigated. Renewable biofuel blends were introduced and examined as energy/sources for desalination plants and, in turn, reduced dependency on fossil fuels, enhanced pollutants, and recovered energy for desalinations. Eight different blended biofuels in terms of dual and ternary blend approaches were investigated. Results displayed that dual and ternary blends of gasoline/n-butanol, gasoline/isobutanol, gasoline/n-butanol/isobutanol, gasoline/bioethanol/isobutanol, and gasoline/bioethanol/biomethanol were all not highly recommended as energy sources for desalination units due to their low heat recovery (they showed much lower than the gasoline, G, fuel); however, they could provide rea... [more]

The interest in employing absorption refrigeration systems is usually related to electricity’s precariousness since these systems generally use thermal rejects for their activation. The application of these systems is closely linked to the concept of energy polygeneration, in which the energy demand to operate them is reduced, which represents their main advantage over the conventional vapor compression system. Currently, the solution pairs used in commercial absorption chillers are lithium bromide/water and ammonia/water. The latter pair has been used in air conditioning and industrial processes due to the ammonia operation’s low temperature. Few review papers on absorption chillers have been published, discussing the use of solar energy as the input source of the systems, the evolution of the absorption refrigeration cycles over the last decades, and promising alternatives to increase the performance of absorption refrigeration systems. There is a lack of consistent studies about des... [more]

In this paper, the aggregate index of green performance of agriculture (Agri-Environmental Index (AEI)) was proposed and empirically verified. For this purpose, a taxonomic method was used, i.e., the linear ordering method, which allows for the construction of a synthetic metric for the assessment of performance. Based on 16 agri-environmental indicators from the Organization for Economic Cooperation and Development (OECD) and Eurostat database, green performance indexes were constructed for 20 European countries. The constructed indexes are based on the multi-line impact of agriculture on the environment, with a particular focus on energy issues. During the analyses, answers to the following research questions were sought: Is the AEI an appropriate tool for evaluating the green performance of agriculture? What is the overall situation in this matter in EU countries? Which areas in terms of the impact of agriculture on the environment require remedial actions? The results of surveys sh... [more]

The current paper analyzes the awareness of renewable energy sources (RES), the relationship between self-reported and actual knowledge, and the correlation among the knowledge of renewable energy sources, the characteristic stereotypes, and the typical attitude of different social groups to energy, comparing them with international experience. A nationwide representative questionnaire-based survey was carried out involving 1002 people in Hungary in 2019. Better education, a higher income, an active white-collar profession, and a health- and environment-conscious approach to life (LOHAS (lifestyle of health and sustainability) segment) are definitely an advantage when it comes to knowledge of renewable energy sources. No significant relationship was detected in terms of age; however, in cluster formation, young people were typically found to be better informed. Overall, the actual knowledge of the Hungarian respondents is more favorable than the self-reported one, and the basic level o... [more]

There is a broad consensus worldwide that anthropogenic climate change is a scientific fact. Likewise, the fact is that the UN’s efforts to address climate change over the last 28 years have not been successful enough. It is evident that the global average temperature is on the rise (1.1 °C above pre-industrial levels in 2019). A particular concern comes from the fact that the Paris Agreement on keeping increases in the global average temperature to below +2 °C is an unenforceable ambition, since the focus is more on consequences than causes. In addition, economic policies regarding global taxes, as well as adaptation and mitigation measures, are questionable, as there is no evidence that changes in the climate system will proceed at the same rate in the coming years. This paper proposes an engineering approach that considers all relevant aspects of the climate change problem and proposes a new policy, named the “Climate New Deal”. It deals with: (i) Reorientation from a high-carbon ec... [more]

This case study investigates the potentials, greenhouse gas (GHG), and energy performance of forest residue biofuels produced by new and emerging production technologies, which are commercially implemented in Sweden for heavy transport. The biofuel options included are ethanol (ED 95), hydro-processed vegetable oil (HVO), and liquefied biogas (LBG) produced from logging residues in forestry and sawdust generated in sawmills. The calculated life cycle GHG emissions, based on the EU Renewable Energy Directive calculation methodology, for all three pathways are in the range of 6−11 g CO2eq./MJ, corresponding to 88−94% GHG emission reductions as compared to fossil fuel. Critical parameters are the enzyme configuration for ethanol, hydrogen supply systems and bio-oil technology for HVO, and gasifier size for LBG. The energy input is ranging from 0.16 to 0.43 MJ/MJ biofuel and the total conversion efficiency from the feedstock to biofuel, including high-value by-products (excluding heat), va... [more]

Poland is one of the leading producers of sugar from sugar beet in Europe. However, the production of sugar generates large amounts of lignocellulosic waste, in the form of beet pulp and leaves. Currently, this waste is not reutilized in the chemical industry, but is only used as food for farm animals. This paper assesses the potential of using bio-waste from the sugar industry as a raw material for the production of furfurals via acid hydrolysis. Further processing of furfural into derivatives such as furfuryl alcohol (FA) or tetrahydrofurfuryl alcohol (THFA) could increase the economic profitability of the initiative. Furfuryl alcohol can be used as a fuel additive in sugar factories. Tetrahydrofurfuryl alcohol can be used as a component in agricultural fertilizers, increasing the yield of sugar beet. This approach reduces the amount of post-production waste and brings the sugar industry closer to the concept of a circular economy.

The energy requirements of a solar-powered exploration rover constrain the mission duration, traversability, and tractive capability under the given limited usable power. Thus, exploration rover design, more specifically, rover wheel design (related to considerable energy consumption in driving), plays a significant role in the success of exploration missions. This paper describes the modeling of an operational environment and a multi-body dynamics (MBD) simulation tool based on wheel-terrain interaction model to predict the dynamic behavior on a digital elevation model (DEM) map. With these simulation environments, a multidisciplinary optimal wheel design methodology, integrating the MBD simulation tool and non-dominated sorting genetic algorithm-II (NSGA-II), is developed. Design parameters are chosen through sensitivity analysis. These multi-objective optimizations in dynamic states are conducted to obtain the optimal wheel dimension that meet the limited power condition with maxima... [more]

This article examines the environmental Kuznets curve for the member countries of the United States−Mexico−Canada Agreement (USMCA), using the ecological footprint as a measure of environmental degradation during 1980−2016. Panel data econometric methods are applied in this research, such as the cross-section dependence, unit root, cointegration and causality tests, and the new method of moments quantile regression (MMQR). The results suggest that the variables are characterized by a cross-section dependence, integrated of order one, and cointegrated. The fully modified ordinary least squares (FMOLS) method shows that renewable energy reduces environmental degradation, and the environmental Kuznets curve is validated. In contrast, patents and trade openness do not show a statistically significant relationship. These results are confirmed with the MMQR, where renewable energy reduces environmental degradation in quantiles from 4 to 6, while the environmental Kuznets curve hypothesis is... [more]

The concept of sustainable economic development takes into account economic, social and environmental aspects and strives to achieve balance between them. One of the basic areas where it is required to revalue the current views on sustainable development is energy. The growing public awareness of environmental protection forces changes in this industry. Despite the global nature of this problem, its solution is perceived differently in various regions of the world. The unquestionable leader in introducing the idea of sustainable development economy is the European Union, where the energy sector is of key importance for the effectiveness of this process. In order to assess the sustainable energy development of the European Union countries, studies were conducted based on 13 selected indicators characterizing this sector in terms of energy, economy and environment. In order to assess the specificity of the European Union countries, these indicators were additionally compared to the gross... [more]

Energy and climate policies benefit from modernized construction technology and energy supply source choices. Energy-efficiency improvement and CO2 emission reduction will result from renewable energy (RE) utilization in new and retrofit single-family houses in rural Poland. Several house construction scenarios and heating energy sources comparing building costs and potential emission reduction are based on already existing structures calculated for a 100 m2 dwelling corresponding to the average rural home. With the addition of thermal insulation and RE-generating equipment, construction costs increase, but the energy costs of operating the home dramatically shrink between a conventional and energy-neutral house. The latter scenario includes thermal solar panels and a heat pump as heating energy sources as well as electricity-generating PV panels. Replacing coal with environmentally-friendly RE reduces CO2 emissions by about 90% annually. Additionally, lower dependence on coal lessens... [more]

Technological solutions allowing the increase of the technological efficiency of anaerobic methods of wastewater treatment are still under investigation. The weaknesses of these solutions can be limited by the use of active fillings. The aim of the present study was to determine the impact of fluidized active filling on the effectiveness of anaerobic treatment of sugar-industry effluent, the production efficiency and the qualitative composition of the biogas produced. High, comparable (p = 0.05) effluent treatment results were observed at tested organic load rates between 4.0 and 6.0 kg COD (Chemical Oxygen Demand)/m3·d. The COD removal rate reached over 74%, biogas yields ranged from 356 ± 25 to 427 ± 14 dm3/kg CODremoved and the average methane contents were approximately 70%. A significant decrease in effluent treatment efficiency and methane fermentation was observed after increasing the organic load rate to 8.0 kg COD/m3·d, which correlated with decreased pH and FOS/TAC (volatile... [more]

Cities constitute three quarters of global energy consumption and the built environment is responsible for significant use of final energy (62%) and greenhouse gas emissions (55%). Energy has now become a strategic issue for local authorities (LAs) and can offer savings when budget cuts have threatened the provision of core services. Progressive LAs are exploring energy savings and carbon reduction opportunities as part of the sustainable and smart city agenda. This paper explores the role of citizens in smart city development as “buildings don’t use energy: people do”. Citizens have the potential to shape transitions towards smart and sustainable futures. This paper contributes to the growing evidence base of citizen engagement in low carbon smart cities by presenting novel insights and practical lessons on how citizen engagement can help in smart city development through co-creation with a focus on energy in the built environment. A case study of Nottingham in the UK, a leading smart... [more]

In this paper, a comprehensive life-cycle assessment (LCA) is carried out in order to evaluate the multiple environmental-health impacts of the biological wastewater treatment of the fish-processing industry throughout its life cycle. To this aim, the life-cycle impact assessment method based on endpoint modeling (LIME) was considered as the main LCA model. The proposed methodology is based on an endpoint modeling framework that uses the conjoint analysis to calculate damage factors for human health, social assets, biodiversity, and primary production, based on Indonesia’s local data inventory. A quantitative microbial risk assessment (QMRA) is integrated with the LIME modeling framework to evaluate the damage on human health caused by five major biological treatment technologies, including chemical-enhanced primary clarification (CEPC), aerobic-activated sludge (AS), up-flow anaerobic sludge blanket (UASB), ultrafiltration (UF) and reverse osmosis (RO) in this industry. Finally, a lif... [more]

With the development of society, the energy crisis has become increasingly prominent, which greatly affects the sustainable development of the economy of various countries. Industrial energy consumption accounts for more than 70% of China’s total energy consumption, of which more than 50% is converted to industrial waste heat, and recyclable waste heat resources account for about 60% of the total waste heat resources, while China’s current utilization rate of industrial waste heat only reaches about 30%. The development of renewable energy and recovery of low-grade waste heat in industry is the key to solve the problem. As a type of volumetric expander with full flow expansion, the screw expander is extensively applied in the industrial waste heat recovery and geothermal energy generation industry because of its effective utilization of low enthalpy energy. Improving the performance of the screw expander as the core, the paper concludes and summarizes the research status of the leakage... [more]

Nowadays, climate change has turned into the leading environmental, technological, social and economical worldwide challenge [...]

In coal seams, depending on the composition of coal macerals, rank of coal, burial history, and migration of thermogenic and/or biogenic gas. In one ton of coal 1 to 25 m3 of methane can be accumulated. Accumulation of this gas is included in unconventional deposits. Exploitation of methane from coal seams is carried out with wells from mining excavations (during mining operations), wells drilled to abandoned coal mines, and wells from the surface to unexploited coal seams. Due to the low permeability of the coal matrix, hydraulic fracturing is also commonly used. Operations related to exploration (drilling works) and exploitation of methane from coal seams were analyzed. The preliminary analysis of the environmental threats associated with the exploration and exploitation of coalbed methane has made it possible to identify types of risks that affect the environment in various ways. The environmental risks were estimated as the product of the probability weightings of adverse events oc... [more]

Human thermoregulation models can predict human thermal responses to evaluate thermal comfort and help create a healthy environment, while their applicability to older people has not been sufficiently validated. This study aimed to evaluate the performance of the Stolwijk model and the Tanabe model for predicting older people’s mean and local skin temperatures under thermal transient conditions. Eighteen healthy older people were recruited and exposed to transient environments including neutral (26 °C), low-temperature (23 and 21 °C), and high-temperature (29 and 32 °C) conditions. The local skin temperatures of the subjects were measured and compared to predictions of the Stolwijk model and the Tanabe model. The results revealed that the Stolwijk model and the Tanabe model could accurately predict the mean skin temperature of older people under neutral and high-temperature conditions, while their predictive accuracy declined under low-temperature conditions. Increased deviations were... [more]

We investigate the environmental impacts of on-board (based on alternating current, AC) and off-board (based on direct current, DC) charging concepts for electric vehicles using Life Cycle Assessment and considering a maximum charging power of 22 kW (AC) and 50 kW (DC). Our results show that the manufacturing of chargers provokes the highest contribution to environmental impacts of the production phase. Within the chargers, the filters could be identified as main polluters for all power levels. When comparing the results on a system level, the DC system causes less environmental impact than the AC system in all impact categories. In our diffusion scenarios for electric vehicles, annual emission reductions of up to 35 million kg CO2-eq. could be achieved when the DC system is used instead of the AC system. In addition to the environmental assessment, we examine economic effects. Here, we find annual savings of up to 8.5 million euros, when the DC system is used instead of the AC system.