Reduce Carbon Dioxide Emissions Research Articles

Advanced Design of Naval Ship Propulsion Systems Utilizing Battery-Diesel Generator Hybrid Electric Propulsion Systems

As advanced sensors and weapons require high power, naval vessels have increasingly adopted electric propulsion systems. This study aims to enhance the efficiency and operability of electric propulsion systems over traditional mechanical propulsion systems by analyzing the operational profiles of modern naval vessels. Consequently, a battery-integrated generator-based electric propulsion system was selected. Considering the purpose of the vessel, a specification selection procedure was developed, leading to the design of a hybrid electric propulsion system (comprising one battery and four generators). The power management control technique of the proposed propulsion system sets the operating modes (depending on the specific fuel oil consumption of the generators) to minimize fuel consumption based on the operating load. Additionally, load distribution control rules for the generators were designed to reduce energy consumption based on the load and battery state of charge. MATLAB/Simulink was used to evaluate the proposed system, with simulation results demonstrating that it maintained the same propulsion performance as existing systems while achieving a 12-ton (22%) reduction in fuel consumption. This improvement results in cost savings and reduced carbon dioxide emissions. These findings suggest that an efficient load-sharing controller can be implemented for various vessels equipped with electric propulsion systems, tailored to their operational profiles.

Reforming Natural Gas for CO2 Pre-Combustion Capture in Trinary Cycle Power Plant

Today, most of the world’s electric energy is generated by burning hydrocarbon fuels, which causes significant emissions of harmful substances into the atmosphere by thermal power plants. In world practice, flue gas cleaning systems for removing nitrogen oxides, sulfur, and ash are successfully used at power facilities but reducing carbon dioxide emissions at thermal power plants is still difficult for technical and economic reasons. Thus, the introduction of carbon dioxide capture systems at modern power plants is accompanied by a decrease in net efficiency by 8–12%, which determines the high relevance of developing methods for increasing the energy efficiency of modern environmentally friendly power units. This paper presents the results of the development and study of the process flow charts of binary and trinary combined-cycle gas turbines with minimal emissions of harmful substances into the atmosphere. This research revealed that the net efficiency rate of a binary CCGT with integrated post-combustion technology capture is 39.10%; for a binary CCGT with integrated pre-combustion technology capture it is 40.26%; a trinary CCGT with integrated post-combustion technology capture is 40.35%; and for a trinary combined-cycle gas turbine with integrated pre-combustion technology capture it is 41.62%. The highest efficiency of a trinary CCGT with integrated pre-combustion technology capture is due to a reduction in the energy costs for carbon dioxide capture by 5.67 MW—compared to combined-cycle plants with integrated post-combustion technology capture—as well as an increase in the efficiency of the steam–water circuit of the combined-cycle plant by 3.09% relative to binary cycles.

Exploring the role of nanoparticle additives in reducing emissions in compression ignition engine

The paper discusses the growing environmental issues caused by vehicle emissions, leading many countries to tighten their emission standards to reduce the harmful gases released by motor vehicles. This is especially important as urbanization has increased, leading to more consumption of petroleum products. As a result, there is a growing need for cleaner, more sustainable fuel alternatives. Biodiesel has been recognized as a potential solution since it is renewable, non-toxic, and less environmentally harmful than traditional diesel. The study in question explores how adding biodiesel and nanoparticles affects diesel engine performance, particularly in terms of noise and particulate matter emissions (small particles of pollution). The research was carried out using a compression ignition engine (like those found in diesel vehicles) under constant RPM (revolutions per minute) and variable loads (changes in engine stress or power requirements). The results showed that when biodiesel was blended with nanoparticles and used as fuel, there was a noticeable reduction in noise levels, carbon dioxide (CO2), and particulate matter emissions compared to regular diesel. This suggests that biodiesel, especially when enhanced with nanoparticles, can effectively lower the harmful effects of diesel engines on the environment, offering a greener and quieter alternative.

Cfd-based optimization of Direct evaporative cooling systems for canarian greenhouses in Semi-Arid regions

Direct Evaporative Cooling Systems (DECS) offer a promising solution for mitigating heat stress in greenhouses located in arid and semi-arid regins. To implement DECS efficiently in these regions, it is crucial to understand their impact on greenhouse microclimate parameters. This study investigates the influence of DECS on the microclimate within a canarian greenhouse and identifies key factors affecting their efficiency. Through Computational Fluid Dynamics (CFD) simulations using Ansys, we examined the effects of DECS on temperature, relative humidity, and air velocity within the greenhouse under semi-arid conditions.The results indicate that DECS efficiency is affected by several factors, including fan placement, evaporative pad height, fan spacing, and inlet air fan speed. Higher fan placement cools the upper canopy but increases humidity near the ceiling, whereas lower placement improves temperature uniformity but may require additional humidification. Closer fan spacing results in uneven air velocity, while wider spacing leads to stagnant zones within the greenhouse. Optimal placement of the the evaporative pad is crucial for maximizing the cooling coverage area and minimizes the temperature gradients. Inlet air fan speed also significantly impacts the microclimate, with higher speeds reducing both temperature and humidity. By optimizing these parameters, the DECS system was able to significantly decrease air temperature, increase humidity, and improve air velocity inside the greenhouse. With a pad height of 1.5 m, fans positioned at a height of 2 m, a distance of 6 m between each fan, and an air speed of 1.5 m/s at the entrance – the DECS enhances the local climate. Under these conditions, the mean air temperature drops from 40°C −in greenhouse with natural ventilation- to 21 °C using DECS, while relative humidity increases from 23 % −in greenhouse with natural ventilation- to 67 % using DECS, creating a more favorable environment for plant growth and potentially increasing crop yield and quality. Additionally, energy and environmental analyses show that implementing DECS in Canarian greenhouses, instead of traditional electrical cooling systems, results in substantial energy savings of 123,818.112 kWh/year annually and reduces carbon dioxide emissions by approximately 1.785 tons/year over a 20-year operational lifespan in a semi-arid climate.

Comparison of Carbon-Dioxide Emissions of Diesel and LNG Heavy-Duty Trucks in Test Track Environment

Environmental protection and greenhouse gas (GHG) emissions are getting increasingly high priority in the area of mobility. Several regulations, goals and projects have been published in recent years that clearly encourage the reduction of carbon dioxide (CO2) emission, the adoption of green alternatives and the use of renewable energy sources. The study compares CO2 emissions between conventional diesel and liquefied natural gas (LNG) heavy-duty vehicles (HDVs), and furthermore investigates the main influencing factors of GHG emissions. This study was carried out in a test–track environment, which supported the perfect reproducibility of the tests with minimum external influencing factors, allowing different types of measurements. At the results level, our primary objective was to collect and evaluate consumption and emission values using statistical methods, in terms of correlations, relationships and impact assessment. In this research, we recorded CO2 and pollutant emission values indirectly via the fleet management system (FMS) using controller area network (CAN) messages. Correlation, regression and statistical analyses were used to investigate the factors influencing fuel consumption and emissions. Our scientific work is a unique study in the field of HDVs, as the measurements were performed on the test track level, which provide accuracy for emission differences. The results of the project clearly show that gas technology can contribute to reducing GHG emissions of HDVs, and LNG provides a reliable alternative way forward for long-distance transportation, especially in areas of Europe where filling stations are already available.

Feasibility assessment of Low-Carbon methanol production through 4E analysis of combined cycle power generation and carbon capture Integration

This study evaluates the feasibility of producing methanol without carbon emissions Using a comprehensive 4E (energy, exergy, economic, and environmental) approach. Our study focuses on a single methanol production system, analyzing its efficiency, sustainability, and potential as a clean fuel production method so that focusing on capturing carbon dioxide from combined cycle power generation and using the generated power to produce hydrogen through ion exchange electrolysis. The systems were simulated using Aspen Plus software, considering practical constraints to align with the capacity of existing power plants. The analysis revealed that the studied methanol production systems can produce 65.3 MW of power, with a net production power of 65.2 MW available for sale to the national grid. The annual methanol production, based on 8,000 operational hours, is 46,086 tons. The cost of methanol production is estimated at $556.69 per ton, and the environmental impact rate was calculated at 0.3726 units, with an exergy efficiency of 31.63 %. The study demonstrates that methanol can be produced efficiently using carbon capture from combined cycles, significantly reducing carbon dioxide emissions. The results suggest that while the system involves high-cost equipment, it effectively balances power generation and methanol production with a relatively low environmental impact. Future research could focus on advanced exergy analysis to identify and mitigate sources of exergy destruction, as well as optimizing carbon capture configurations and integrating solar thermal energy to enhance system sustainability further.

ASSESSING PROGRESS TOWARDS A CIRCULAR CARBON ECONOMY IN THE G20 COUNTRIES

As cornerstones of worldwide sustainable development, the circular economy and the circular carbon economy are profoundly interrelated. However, opinions differ on how to optimize the circular economy towards reducing carbon dioxide emissions. This article aims to investigate the different levels of readiness for the circular carbon economy within G20 member countries in the domain of economic efficiency. In that regard, a selection of circular carbon economy sub-indicators has been analysed. Through the use of secondary data, tendencies towards change in this variability were found. The degree of adoption of a circular carbon economy differs among the G20 economies. In terms of the various factors considered in the G20 member countries, the current analysis has determined that there continue to be substantial differences between the best performers and their enabling factors.

On the politics of constitutional law: an environmental case study of the role of politics and economics in constitutional appeals

AbstractThe U.S. government has responded to concern about climate change through regulation of carbon-dioxide emissions by the Environmental Protection Agency under the Clean Air Act. Regulation of the electric power industry has been central to the fight to reduce carbon-dioxide emissions, but these regulations have been challenged by constitutional appeals that have resulted in episodic advances and reversals. Grounds for constitutional appeal of environmental laws are many, but at their core is the question of whether a given law is consistent with the constitution. If constitutionality is central to the positions the attorneys general take on appeals of environmental regulations, political and economic factors should not affect their positions. Empirical evidence presented in this case study shows, however, that these factors are correlated with the positions the attorneys general of the U.S. states and District of Columbia took towards constitutional appeals of regulations of carbon-dioxide emissions from the electric power industry. At a broader level, these findings shed useful light on the question of how constitutional appeals are brought.

RESEARCH OF THE ACTIVITIES OF PEASANT FARMS IN KAZAKHSTAN IN THE CONTEXT OF EFFECTIVE ENERGY CONSUMPTION

Some of the concepts that can be identified with agriculture in Kazakhstan include farmers and livestock breeders. Nowadays, the concept of agriculture is inextricably linked with the concepts of efficient energy consumption and "green" farming, thus there is a need to improve the use of renewable energy sources. Ensuring the efficient use of energy has advantages in the form of lower production costs and social benefits in the form of reducing carbon dioxide emissions to a level that does not harm the environment, in support of sustainable development of agricultural regions. The purpose of the article is to analyze the impact of the use of renewable energy sources on the development of peasant farms. In particular, it is planned to identify factors related to renewable energy sources in terms of agricultural development, profitability, and their impact on the environmental component. In this context, an analytical comparison of installed renewable energy capacities and indicators of reducing the cost of CO2 emissions due to energy-efficient technologies of the new generation was carried out.

Transesterification of biodiesel from kapok seed oil (ceiba pentandra) using a natural heterogeneous katalyst (rice husk activation)

Biodiesel as a renewable energy source can be produced by a chemical reaction between vegetable oil or animal fat and short-chain alcohol such as methanol, ethanol or buthanol and is supported by a catalyst. This process is called transesterification. From an environmental point of view, the use of biodiesel has several advantages such as reducing carbon dioxide emissions, being non-toxic and biodegradable. Kapok seed oil has potential for exploitation, particularly as a raw material for the manufacture of biofuel. Kapok seeds (Ceiba pentandra) have the potential to be used as a feedstock for biodiesel because their oil content is quite high, around 18-25% oil. The controlled combustion of rice husks produces ash containing high purity amorphous silica. Amorphous silica can be obtained from RHA (rice husk ash) when rice husk is burned at a temperature of 700°C, and it is transformed into crystalline silica when burned at a temperature above 850 °C. This silica has many applications as a filler, adsorbent, catalyst support, star gel component and source for the production of premium silicon and its compounds. The aim of the research is to determine the transisterification process of biodiesel from kapok (Ceiba pentandra) seed oil. using a natural heterogeneous catalyst in It is an activated rice husk. The method used was the preparation of kapok seed samples and the extraction of sokhlet. Determination of free fatty acids (FFA) in kapok seed oil, activation of rice husk, manufacturing of biodiesel from kapok seed with addition of rice husk H2SO4 as catalyst. The characteristics of the biodiesel produced are Density: 859.88572 kg/m3 (SNI: 7182:2015) = 850-890 kg/m3), Viscosity: 2.45824 cSt (SNI: 7182:2015) = 2.3 – 6, 0 cSt, Calorific value: 7,374.5322 cal/g (SNI: 7182; 2015) = 7,100 -11,000 cal/ g, Devil's number: 48 (ASTM: D6751) = 47. Meanwhile, GC-MS with the highest values at all reaction times, namely Hexadec anoic acid, methyl ester (C17H34O2), methyl tetradecanoate (C15H30O2) and 9 - Octadecenoic acid (Z), methyl ester (C19H36O2) . The functional group found in kapok seeds is –OH.

Experimental performance evaluation of direct cooling of hot stamping dies using fractal cooling channels

Hot stamping is a promising technology to reduce carbon dioxide emissions in the transportation industry by decreasing the weight of components with appropriate strength. However, the low cooling performance of conventional indirect cooling channels degrades the product quality and production rate during hot stamping. This study proposes a novel direct cooling system for hot stamping dies with fractal cooling channels (FCCs). Based on experiments, the cooling performance of the FCC was analyzed at various press holding times, mass flow rates, and cycle numbers. In the FCC, the average blank temperature at a water mass flow rate of 50 kg h−1 was 22 % lower than that at a zero-mass flow rate. At a mass flow rate of 50 kg h−1, the average blank temperature in the FCC increased with the cycle number and converged to 186 °C in the seventh cycle. Additionally, the standard deviation of the temperature distribution in the FCC was on average 39 % lower than that in the straight cooling channel (SCC). Finally, the daily production rate in the FCC was 34 % higher than that in the SCC.

The impact of calcined mud on the rheological properties of eco-friendly concretes using the equivalent mortar method (CEM)

In order to harmonise technical and environmental aspects, people today focus not only on concrete's technical characteristics but also on environmental imperatives. Thus, the emphasis is on the development of concrete and cements that offer ecological and sustainable advantages. Commonly, people use various natural materials as cement additives, demonstrating their effectiveness by replacing a significant portion of the cement in the hardened state of concrete. This substitution leads to a substantial and remarkable reduction in carbon dioxide emissions. However, when it comes to the physical properties of the material in its fresh state, challenges may arise. Indeed, the rheological changes induced by these additives may hinder the on-site use of this eco-concrete. The main purpose of this study is to find out how adding minerals to environmentally friendly concrete changes its rheological parameters (yield stress, plastic viscosity) and fresh properties (slump, flow time). We will approach this using the concept of mortar equivalent to concrete (CEM). We developed five formulations of CEM’s by substituting cement with calcined mud (CM) in binary mixing systems at a temperature of 20 °C. The results showed that adding binary cements with calcined mud had a negative effect on the fresh properties and rheological parameters. However, when substitution happens at a low rate, it behaves almost like control mortar (OPC).

Specific features of production and use of transportation biofuels in selected developing countries (part II)

Aim. To identify specific features of production and use of transportation biofuels in selected developing countries, as well as to assess the potential of bioethanol industry development in the Russian Federation (RF).Objectives. To assess the economic efficiency of bioethanol production in Russia; to reveal the potential of applying foreign experience in the development of bioethanol industry in our country.Methods. In the process of the research the methods of system analysis, comparative analysis, method of expert evaluations, mathematical, statistical methods were applied.Results. The actual estimation of economic efficiency of bioethanol production in Russia was obtained. The cost of a unit of bioethanol, which is equivalent to a liter of gasoline in terms of energy content, is 5-36% higher than the cost of a liter of gasoline (depending on the production technology). At the same time, state support for the production and use of bioethanol in our country is reasonable. This will allow to create additional demand for grain crops and reduce carbon dioxide emissions from motor transport. The production and use of bioethanol will form an additional supply in the gasoline market, will give an opportunity to support projects on deep processing of grain and wood chemistry.Conclusions. The experience of Brazil, China and Indonesia in the development of bioethanol industry is relevant for Russia. At the same time, in order to minimize possible risks in the field of food security at the initial stage of bioethanol industry development, low-quality grain stocks should be used as feedstock and the production of second-generation bioethanol should be stimulated.

Green Order Sorting Problem in Cold Storage Solved by Genetic Algorithm

This study investigates the efficiency of cold storage warehouses and contributes to sustainable supply chain management by integrating eco-friendly practices into storage operations. In facilities for milk and its derivatives, unregulated order handling significantly increases energy consumption due to frequent door openings in the cooler. To address this challenge, we developed a novel mathematical model aimed at optimizing order sequences and minimizing energy costs, addressing a previously unexplored gap in the literature. A genetic algorithm (GA) was employed to solve this model, with careful consideration of carbon emissions generated during the algorithm’s execution. We utilized the Yates notation, an experimental design technique, to systematically optimize the GA’s parameters, ensuring robust and statistically valid results. This methodology enabled a thorough analysis of the factors influencing energy consumption. The findings enhance energy efficiency in cold storage warehouses, leading to reduced carbon dioxide emissions and fostering sustainable practices within supply chain management. Ultimately, this study successfully integrates green practices into cold storage operations, supporting broader sustainability objectives.

Cradle-to-gate analyses of biochar produced from agricultural crop residues by vacuum pyrolysis

Abstract Agricultural waste, if not managed efficiently, can pose significant environmental threats. Biochar production, a cost-effective solution, offers a potential to significantly reduce carbon dioxide emissions and thereby combat climate change. However, the environmental impact of this process is not uniform and varies depending on the agricultural residue used. These impacts, spanning the entire lifecycle from cultivation to disposal, underscore the necessity of a thorough assessment before biochar can be widely adopted for practical applications. This study employs a cradle-to-gate approach to evaluate the life cycle assessment (LCAs) of producing biochar from various agro-residues, such as rice husk, sugarcane bagasse (SB), and corn cob (CC). The LCA was conducted using SimaPro software, version 9.5.0.1, and the ReCiPe impact assessment method. The results indicate that CC cultivation has the highest impact across most categories, while rice husks exhibit higher water consumption (2.8 × 103 m3). Using diesel, electricity, and fertilizers significantly contributes to global warming potential (GWP). SB shows the most negligible impact during biomass cultivation. However, pyrolysis processes exhibit high implications on various indicators. Applying biochar to soil for carbon sequestration and improvement can reduce GWP. Sensitivity analysis demonstrates a notable reduction in GWP and cumulative energy demand, approximately 10%–24% and 4–11 MWh, respectively. Paddy cultivation and rice husk biochar production have a lesser environmental impact. Changing energy sources during biomass growth and biochar production significantly influences environmental factors.

Metaheuristic optimizing energy recovery from plastic waste in a gasification-based system for waste conversion and management

In an era where sustainable waste management and clean energy production are paramount, this study presents an innovative integration of plastic waste gasification with solid oxide fuel cell (SOFC) technology, optimized through metaheuristic particle swarm optimization (PSO). The research explores the conversion of polypropylene (PP) waste into syngas via gasification, which is then utilized as a fuel for SOFCs to generate electricity. The optimization process focuses on maximizing power and heating outputs while minimizing carbon dioxide emissions. The study's findings demonstrate the potential of integrating gasification and SOFC technologies to create a sustainable energy system that addresses the challenges of plastic waste. Key findings from the metaheuristic PSO multi-objective optimization reveal that optimal power production, approximately 360 kW, is achieved at temperatures exceeding 1140 K, irrespective of the steam/PP waste ratio. Heating production peaks at 1000 kW with temperatures above 1120 K and utilization factors over 0.765, while the minimum heating output is 700 kW. Emission analysis indicates a significant reduction in carbon dioxide emissions with increased temperatures and utilization factors, achieving a minimum of 700 kg/MWh at temperatures above 1120 K. The study's results demonstrate the effectiveness of the PSO optimization in fine-tuning the operational parameters of the integrated system, leading to improved energy efficiency and reduced environmental impact. Power production of 366.37 kW, a significant heating rate of 995.20 g/s, and emissions of 714.06 kg/MWh are the optimum performances. The research provides valuable insights into the potential of plastic waste-to-energy technologies as sustainable solutions for energy production and waste management.

Study on the properties and eco-sustainability of early-age carbonation cured cement paste with recycled concrete slurry waste substitution

The reduced early-age properties of cementitious materials substituted recycled concrete slurry waste (RCSW) hinder its utilisation, which can be further improved via early-age carbonation curing with benefits from sequestering the CO2. This study aims to compressively investigate the effectiveness and environmental impact of early carbonation curing on three replacement ratios and three types of treatments of RCSW including sieving, shearing and ball milling with standard curing. In addition to mechanical properties, hydration properties, microstructure characteristics, and carbon sequestration of the treated-RCSW replaced cement paste after different curing methods were investigated and compared. The results showed that, compared to substitution ratios of 30 % and 45 %, cement paste with a 15 % RCSW substitution ratio exhibited higher strength. Furthermore, compared to standard curing, the carbonation curing method effectively improved the early strength and overall performance of the cement paste, with the early strength under carbonation curing at a 15 % RCSW substitution rate being about 89 % higher than that of standard curing. According to economic and environmental calculations, RCSW substitution could effectively reduce carbon dioxide emissions, and the use of carbonised curing methods enabled the cement paste to effectively absorb carbon dioxide.

Exploring the Nexus between Greenhouse Emissions, Environmental Degradation and Green Energy in Europe: A Critique of the Environmental Kuznets Curve

This study examines the intricate relationship between economic growth and European environmental degradation via the Environmental Kuznets Curve (EKC). Our results contest the traditional inverted U-shape model of the Environmental Kuznets Curve, indicating that the theory may not be consistently applicable across European countries. Utilizing CS-ARDL and MMQR modelling, we reveal substantial regional disparities. Western European nations demonstrate a typical Environmental Kuznets Curve (EKC) pattern in the short term, characterized by an initial increase in emissions alongside GDP development, followed by a subsequent fall. Conversely, Eastern and Balkan nations exhibit a U-shaped connection, described by an early decline in emissions followed by a subsequent increase as their development levels increase. The influence of renewable energy differs, as it decreases emissions in the short term in Western Europe. However, its long-term impacts are variable, especially when contrasted with its more pronounced effect on emissions in Eastern and Balkan countries. Furthermore, trade openness intensifies environmental degradation in the short-term across all regions, although its long-term impact diminishes, particularly concerning greenhouse gases (GHG). The relationship between renewable energy and trade openness is substantial for the short-term reduction of carbon dioxide emissions, but this effect declines with time. The results indicate that a uniform environmental policy throughout Europe may lack efficacy. Customized strategies to expedite the transition in Western Europe and more specific interventions in Eastern Europe are essential to harmonize economic progress with environmental sustainability. Future research should examine the determinants of the diminishing long-term effects of renewable energy and the interplay between trade and environmental policies.

Optimising Portugal’s 2050 energy system: Electric vehicles and hydrogen integration using Grey Wolf Optimiser and EnergyPLAN

The global shift to sustainable energy, driven by climate concerns and energy security, is backed by worldwide governmental commitments to reduce greenhouse gas emissions and enhance renewable energy sources in the energy systems. In 2016, the Portuguese Government pledged to carbon neutrality by 2050 as part of this global effort. This article proposes technical solutions for reducing carbon dioxide emissions and increasing renewable energy in the Portuguese mainland energy system by 2050, considering the targets set by the government. An energy system modelling approach based on the Grey Wolf Optimiser and the EnergyPLAN software was introduced. Seven scenarios for 2050 assess the impacts of transport electrification and hydrogen grid integration while minimising costs and/or carbon dioxide emissions. The results show that achieving a nearly 100% renewable electricity system and carbon neutrality is possible, considering a carbon capture ranging from 2.65Mt to 5.87Mt. The 2050 energy system requires a minimum battery storage of 5.1GWh and a minimum natural gas storage of 2,063GWh. Transport electrification requires an increase in the total installed capacity by at least 1.83GW, while hydrogen integration increases it by a minimum of 8.25GW. Developing interconnection capacity beyond 15% of the total installed capacity is crucial for grid stability and reducing fossil fuel dependence.

Spatiotemporal influence of the digital economy on the industrial green transition from the perspective of pollution and carbon dioxide emission reduction

Spatiotemporal influence of the digital economy on the industrial green transition from the perspective of pollution and carbon dioxide emission reduction