Fuel Reduction Research Articles

Investigating Fuel Reduction Methods Through Propeller Optimization on Coastal Ro-Ro Liner Vessels

In light of efforts to reduce GHG emissions, liner ship operators in coastal navigation are undertaking numerous activities to contribute to the reduction of fossil fuel consumption during the transitional period toward environmentally friendly propulsion systems without compromising their regular operations. Regular ship overhauls, which include removing fouling from the underwater part of the hull and optimizing propellers, also contribute to this goal and are the focus of this research. The ship propeller, as a key component of the propulsion system, plays a significant role in ensuring reliable, safe, and economical navigation. Proper selection and regular maintenance of the propeller are essential for achieving optimal performance. This paper presents the optimization of a fixed-pitch propeller according to the ISO 484/2 standard to Class I using Metrascan 3D technology. This technology enables a detailed analysis of the propeller geometry, identification of irregularities, correction, and adjustment to achieve better hydrodynamic characteristics. The pitch corrections of the propeller resulted in improved overall vessel performance and fuel consumption, as demonstrated by comparing the consumption before and after the optimization.

Recyclable palladium nanocatalyst for effective organic pollutants removal through reduction☆

Palladium is a metal catalyst with excellent performance, but its application is severely restricted due to low atomic utilization and weak recovery capacity. To address these issues, we prepared a palladium nanocatalyst through a universal nanocatalysts preparation strategy. It has a particle size of less than 100 nm, possesses good superparamagnetism, and its saturation strength is 71.48 emu/g. It demonstrates outstanding catalytic properties in the reduction and decolorization of organic fuels, and the achieving conversion rates are 92 %, 99 %, and 97 % for methylene blue, rhodamine B, and methyl orange, respectively. Additionally, it can catalyze the hydrogenation dehalogenation of p-chlorophenol, with a 100 % conversion rate and selectivity. The nanocatalyst shows outstanding recyclability in the test of recyclability. Therefore, our results show that the palladium nanocatalysts have attractive characteristics of simple preparation, excellent catalytic activity and reusability. This work lays the foundation for the preparation of palladium nanocatalysts and their potential applications in areas like environmental pollution treatment.

FOREST MANAGEMENT IN PORTUGAL

Portugal and occupied by more than 1/3 of forests. Portuguese legislation on forests has progressively changed over time, with measures being created that take the Portuguese panorama and problems into account. Portuguese forests present several advantages at a humanitarian, economic and social level. Their contribution to the national economy forest production and foreign trade, forest energy, recreational and tourism. In the Portuguese context, fires are the biggest problem that Portugal faces today. Rays, Arsonists, Burning for cleaning, Smokers and Country fires are examples of the causes. There is a certain impact on time and space indirectly and directly. Fuel reduction in strategic locations and changes in behaviors by the population could be the solution for what we have been looking for.

A Design of Economically Feasible Hybrid Energy System with Renewable Energy Ratio Priority

The reduction of fossil fuels which produce CO2 emission that damage the environment, can be done by implementing renewable energy-based power generations, such as solar and wind. This research designs a hybrid energy system by optimizing the use of existing diesel generators through the integration of renewable energy sources, such as solar photovoltaic and micro wind turbine, and is equipped with an energy storage system. This research uses HOMER Pro software to determine the optimal capacity of hybrid system components, and to calculate the cost of energy (CoE). Furthermore, the hybrid system configuration is analyzed by applying several objectives. The objectives of the hybrid system design are to prioritize a maximum renewable energy penetration ratio within permitted annual capacity shortage and with the CoE lower than the existing CoE. The research results show that the proposed hybrid energy system can provide a renewable energy penetration ratio of 57.1% with CoE of IDR 3,510/kWh.

Review of Recent Applications of Heat Pipe Heat Exchanger Use for Waste Heat Recovery

With the reduction in fossil fuels and growing concerns about global warming, energy has become one of the most important issues facing humanity. It is crucial to improve energy utilization efficiency and promote a low-carbon transition. In comparison with traditional heat exchangers, heat pipe heat exchangers indicate high compactness, a flexible arrangement, complete separation of hot and cold fluids, good isothermal operations, etc. As a result, heat pipe heat exchangers have attracted wide attention and application in various fields in recent years. This paper provides an overview of the application of heat pipe heat exchangers, with a focus on the application in waste heat recovery, and analyzes the opportunities and challenges of heat pipe heat exchanger applications based on existing publications.

Trends in prescribed fire weather windows from 2000 to 2022 in California

As increasing wildfire activity puts pressure on wildland fire suppression resources both nationally and within the state of California, further development of programs and infrastructure that emphasize preventative fuels treatments, e.g. prescribed burning, is critical for mitigating the impacts of wildfire at large spatial scales. Among many factors that limit the use of prescribed fire, weather and fuel moisture conditions are among the most critical. We analyzed a 2-km gridded hourly surface weather dataset over a 23-yr period to explore the relationship between climatological trends and prescribed fire weather windows. Pairing this dataset with burn prescription parameters provided by experienced regional fire practitioners, we seek to identify the timing and extent of changes in weather-related opportunities for prescribed fire in two distinct geographic regions within California. We found an increasing trend in opportunities for prescribed fire use in Sonoma County, a representative coastal Mediterranean region of CA, and a decreasing trend in Plumas County, a montane region that extends through the Northern Sierra Nevada. Seasonally, we see more nuances—increased winter opportunities in both counties, as well as increased summer opportunities in Sonoma. Most notably, we see great variation spatially in the occurrence of suitable weather windows for prescribed burning. Fire management resource availability and air quality regulations further constrain burn windows. We observed a greater influence of these factors in Sonoma County vs. Plumas. Resource availability is the greatest constraint in the Summer and Fall, during wildfire season, and air quality regulations are a greater constraint in the Winter. Our findings provide information to decision-makers and regulators at the county and other government levels to more effectively support use of prescribed fire to achieve land management and fuels reduction goals.

An integrated vendor-buyer model with sustainability and remanufacturing of returned product

Carbon emission reduction is very crucial nowadays. A proper balance is required for carbon emission reduction and burning of fossils fuels because during fossil fuel burning carbon is emitted and it is essential for industrialization. This study presents an inventory model with green technology where production of new items and remanufacturing of returned items are allowed. Remembering the present global situation, the ordering cost is assumed as variable cost which contain order cancellation and reorder cost. Online order policy is considered with quality of product and a return rate. Keeping in mind the social, economic and environmental aspects, the demand function is considered as sustainability sensitive demand. A nonlinear model is designed based on the above concepts. The model is solved both theoretically and analytically. The main motives of the work are to find the effects of ordering cost, carbon emission cost and green technology investment on the inventory model for suggesting the best policy to the inventory manager. Sensitivity analysis is performed to validate the model. The numerical results prove that ignoring ordering cost, carbon emission cost and green technology investment can lead to a false optimal solution and this can be a huge economical loss for the inventory manager. The results also prove that a sustainable model with carbon emission and green technology investment is more realistic and profitable in compare with the other existing models.

Constraints on Mechanical Fuel Reduction Treatments in United States Forest Service Wildfire Crisis Strategy Priority Landscapes

Abstract The USDA Forest Service recently launched a Wildfire Crisis Strategy outlining objectives to safeguard communities and other values at risk by substantially increasing the pace and scale of fuel reduction treatment. This analysis quantified layered operational constraints to mechanical fuel reduction treatments, including existing vegetation, protected areas, steep slopes, and administrative boundaries in twenty-one prioritized landscapes. Results suggest that achieving the objective to treat 20%–40% of high-risk area is unlikely in most landscapes under a business-as-usual approach to mechanical fuel reduction treatments. Increased investment in steep-slope systems and expanded road access opens sufficient acreage to meet treatment objectives in eighteen of twenty-one priority landscapes. Achieving treatment objectives in the remaining three landscapes will require both increased investment to overcome physical constraints and navigating administrative complexities within reserved land allocations to implement fuels treatments at the pace and scale needed to moderate fire risk to communities. Study Implications: Legal, operational, and administrative factors have hindered the implementation of proposed wildland fire risk reduction management actions. Investing in steep-slope systems, expanding use of temporary roads, and revising administrative rules to allow for appropriately tailored mechanical thinning in special conservation areas are possible ways to meet fuel reduction treatment objectives of the USDA Forest Service Wildfire Crisis Strategy in twenty-one landscapes across the western United States. Broadening the land base available for mechanical treatment allows for flexibility to develop treatment plans that optimize across the multiple dimensions of effective landscape-scale fuel treatment design and restore fire as a key ecosystem process.

Unexpected Trade-Offs of Fossil Fuel Reduction on PM2.5 and O3 Pollution Regulation Can Be Offset by Synergistic Control of VOCs Source

Unexpected Trade-Offs of Fossil Fuel Reduction on PM_2.5 and O₃ Pollution Regulation Can Be Offset by Synergistic Control of VOCs Source

Many Benefits Realized After a Long‐Term Fuel Reduction and Restoration Study in Western Montana

Many Benefits Realized After a Long‐Term Fuel Reduction and Restoration Study in Western Montana

Sustainable hydrogen supply chain development for low-carbon transportation in a fossil-based port region: A case study in a tourism hub

This study combines an investigation of Kish Island's transition to sustainable energy and transportation with a focus on the integration of hydrogen port infrastructure, employing nonlinear optimization to chart the path forward. It emphasizes the pivotal role of such infrastructure in transitioning from traditional vehicles and gas-fired power, evaluating scenarios like a 30% reduction in fossil fuels and the implementation of carbon taxes to encourage a shift to electric and hydrogen-powered vehicles. Forecasts suggest an increase in electric vehicle adoption to 46% by 2023, with a goal of complete electrification by 2042, thereby transforming the energy landscape and reducing emissions. Key to this transition is a 25% government subsidy on hydrogen vehicles to enhance market competitiveness, alongside the strategic embedding of hydrogen infrastructure within sustainable tourism zones. This approach creates a synergistic model of energy, transport, and environmental stewardship, aiming to elevate regional prosperity and sustainability. The study extends its innovative perspective to include the exploration of methanol production, the development of carbon markets, and the advancement of Carbon Capture and Storage (CCS) technology, positioning the hydrogen port as a crucial element in Kish Island's sustainable development strategy.

Promote the decarbonization pathways of eco-industrial parks by considering their CO2 emissions structures and characters

China has proposed the goals of a carbon peaking target in 2030 and a carbon neutrality target in 2060 to mitigate climate change. In China, Eco-industrial parks (EIPs) are one of the platforms for achieving energy conservation and emission reduction. This study aims to investigate the future CO2 emissions reduction potential by evaluating two different types of national EIPs in China. Firstly, we constructed carbon emission inventories for EIP-N in Zhejiang Province and EIP-L in Shandong Province. Subsequently, leveraging these inventories, we developed an integrated model aimed at predicting the carbon emission peaks for both EIPs and discerning the main contributors. Secondly, we took EIP-N and EIP-L as examples and applied the Long-range Energy Alternatives Planning (LEAP) model to establish three different scenarios for analyzing the future trends in carbon emissions. In a Business as usual (BAU) scenario (continue the current energy conservation and emission reduction policies), EIP-L can achieve carbon peaking, while the carbon emissions of EIP-N will continue to increase. In the Emissions control (EMC) scenario (considering the reduction of fossil fuels and the increased use of cleaner energy sources), EIP-N and EIP-L are projected to peak in 2029 and 2027, respectively. In the Reinforce mitigation (RFM) scenario (with fewer emissions from fuels and a higher share of clean energy generation), both EIPs are expected to achieve carbon peaking by 2025. Finally, we proposed the deep decarbonization of EIPs with different industrial characteristics. This study applied the LEAP model to the EIP scale, explored the paths of deep decarbonization development in different EIPs under the constraint of dual-carbon targets, providing a demonstration for China and other developing countries to achieve the goal of carbon capping in EIPs during rapid industrialization.

Incorporating burn heterogeneity with fuel load estimates may improve fire behaviour predictions in south-east Australian eucalypt forest

Background Simulations of fire spread are vital for operational fire management and strategic risk planning. Aims To quantify burn heterogeneity effects on post-fire fuel loads, and test whether modifying fuel load estimates based on the fire severity and patchiness of the last fire improves the accuracy of simulations of subsequent fires. Methods We (1) measured fine fuels in eucalypt forests in south-eastern Australia following fires of differing severity; (2) modified post-fire fuel accumulation estimates based on our results; and (3) ran different fire simulations for a case-study area which was subject to a planned hazard reduction burn followed by a wildfire shortly thereafter. Key results Increasing fire severity resulted in increased reduction in bark fuels. In contrast, surface and elevated fuels were reduced by similar amounts following both low-moderate and high-extreme fire severity. Accounting for burn heterogeneity, and fire severity effects on bark, improved the accuracy of fire spread for a case study fire. Conclusions Integration of burn heterogeneity into post-burn fuel load estimates may substantially improve fire behaviour predictions. Implications Without accounting for burn heterogeneity, patchy burns of low severity may mean that risk estimations are incorrect. This has implications for evaluating the cost-effectiveness of planned burn programmes.

Do Vegetation Fuel Reduction Treatments Alter Forest Fire Severity and Carbon Stability in California Forests?

AbstractForest fire frequency, extent, and severity have rapidly increased in recent decades across the western United States (US) due to climate change and suppression‐oriented wildfire management. Fuels reduction treatments are an increasingly popular management tool, as evidenced by California's plan to treat 1 million acres annually by 2050. However, the aggregate efficacy of fuels treatments in dry forests at regional and multi‐decadal scales is unknown. We develop a novel fuels treatment module within a coupled dynamic vegetation and fire model to study the effects of dead biomass removal from forests in the Sierra Nevada region of California. We ask how annual treatment extent, stand‐level treatment intensiveness, and spatial treatment placement alter fire severity and live carbon loss. We find that a ∼30% reduction in stand‐replacing fire was achieved under our baseline treatment scenario of 1,000 km2 year−1 after a 100‐year treatment period. Prioritizing the most fuel‐heavy stands based on precise fuel distributions yielded cumulative reductions in pyrogenic stand‐replacement of up to 50%. Both removing constraints on treatment location due to remoteness, topography, and management jurisdiction and prioritizing the most fuel‐heavy stands yielded the highest stand‐replacement rate reduction of ∼90%. Even treatments that succeeded in lowering aggregate fire severity often took multiple decades to yield measurable effects, and avoided live carbon loss remained negligible across scenarios. Our results suggest that strategically placed fuels treatments are a promising tool for controlling forest fire severity at regional, multi‐decadal scales, but may be less effective for mitigating live carbon losses.

Europe’s independence from Russian natural gas — Effects of import restrictions on energy system development

With the Russian invasion on Ukraine in 2022 and the following disruption of Russian natural gas imports, Europe’s energy reliance on Russia has become more apparent than ever. To tackle the resulting challenges of a limited supply of fossil fuels from Russia and especially its effects on energy system development, short and long-term effects need to be investigated thoroughly. This paper aims to quantitatively analyze the impact of reduced natural gas availability from Russia on the European energy system, both in the coming years, as well as in the future. Using the Global Energy System Model (GENeSYS-MOD), three scenarios with varying amounts of Russian natural gas and further impacts of reduced fossil fuel imports from Russia are calculated. Results show that strong effects are mostly observed in the short to medium-term, but an overall earlier phase-out of fossil fuels can be achieved in the long-term. The reduction of natural gas imports is tackled by an increase in LNG imports and domestic natural gas production to overcome the supply gap. Strong reactions are seen in the levelized costs of electricity generation between 2022 and 2025, with higher costs in scenarios with restrictions on Russian natural gas imports, but with a negligible difference in the long-term. Most importantly, lower emissions in scenarios with reduced natural gas supply from Russia highlight the positive effect of an early reduction in fossil fuels and investment in renewable technologies, resulting in a near 100% emission-free energy system by 2045, 5 years before the Base scenario with unrestricted Russian gas imports. The results find that a limitation of Russian fossil imports does not pose a long-term threat to the European energy system or its required transition away from fossil fuels, but can rather accelerate its decarbonization and energy demand reductions.

Multi-objective optimization and analysis of chemical kinetics properties: Exploring the impact of different hydrogen blending ratios on LPG and methane-air mixtures

The use of hydrogen with hydrocarbon fuels like methane and LPG is crucial for carbon neutrality and environmental goals. United Nations Environment Programme (UNEP) and the International Energy Agency (IEA) emphasise reducing LPG and methane emissions to prevent temperature increases. Utilising H2-LPG and H2-CH4 blends enhances free radical formation, mitigates emissions, and combats global warming. Using the CHEMKIN tool, this research compares the combustion characteristics of H2-CH4-air and H2-LPG-air mixtures under atmospheric conditions and different operating conditions. Blending 50 % hydrogen with LPG and methane yields notable variations, including a 20.97 % higher flame speed in H2-CH4, 42.89 % more H free radical formation in H2-LPG, 50.24 % reduction in O free radical formation in H2-LPG, and a 24.01 % increase in OH free radical formation in H2-LPG. The study investigates the energy and environmental impacts of incorporating hydrogen into CH4-air and LPG-air combustion, focusing on 50 % H2 blending with LPG. The benefits of hydrogen blending encompass heightened flame speed and augmented free radical formation, ultimately contributing to emission reduction in hydrogen-blended fuels. These findings highlight H2-LPG and H2-CH4 blends as environmentally friendly alternatives with improved combustion.

Reducing energy poverty by nearly universal pension coverage of rural China

This paper estimates the causal effect of income change on reducing energy poverty by exploiting age-based eligibility for China’s New Rural Pension Scheme (NRPS) through a regression discontinuity (RD) design. More than one billion people worldwide live in energy poverty, and the situation is even more difficult in developing world. It is an important development challenge to reduce energy poverty, which could be further associated with health outcome, labor productivity, and educational achievements. While public policies that increase income for poor households are the most direct ways to reduce energy poverty, the reverse causality makes establishing a convincing causal link between income and energy poverty challenging. Using the quasi-experimental variation in income induced by NRPS, this paper addresses the endogeneity of income and examines the impact of exogenous sharp changes in income on energy consumption behaviors. The findings indicate substantial increases in modern energy consumption and sizable reductions in solid fuels (e.g., straw and fuelwood), suggesting that “windfall income” by pension coverage alleviates energy poverty. Although individuals could anticipate the income shocks by pension coverage, the evidence suggests that they do not engage in anticipatory responses to smooth their consumption. Further evidence shows that liquidity constraints may be the underlying mechanism for the lack of anticipatory responses in household energy consumption. Besides reducing energy poverty, the results demonstrate that pension coverage leads to a decrease in elderly labor supply, an increase in subjective health and life satisfaction, and an increase in non-energy consumption, all of which are positively associated with the well-beings of senior citizens. We anticipate that the findings of this paper in the context of China may be extended to developing world which has been expected to set up targeted measures to tackle energy poverty in upcoming decades.

Regulating CHO* intermediate pathway towards the significant acceleration of photocatalytic CO2 reduction to CH4 through rGO-coated ultrafine Pd nanoparticles

Tailoring catalytic reaction pathways by using reduced graphene oxide (rGO) to tune the electron-hole separation channels in the active sites of noble metals for achieving ideal yield and selectivity in photocatalytic CO2 reduction of hydrocarbon fuels remains a challenge. Herein, ternary catalyst of rGO-coated SnO2-supported noble metal Pd nanoparticles (Pd4/SnO2@rGO) has been prepared by coassembly between negatively charged graphene oxide and positively charged Pd nanoparticles. By coating with ultrathin rGO, the selectivity can be shifted from CO (44.69 % for Pd4/SnO2) toward CH4 as the prevalent species, in which the Pd nanoparticles acted as catalytic sites and electron capture sites. The rGO coating reduced the recombination of the photogenerated carriers as well as optimized the band gap and reduction potential of the catalyst. The in situ spectroscopic tests and density functional theory calculations revealed that CO2 adsorbed on Pd nanoparticles selectively formed dominant low-energy CHO* intermediates because of the generation of HCOOH* intermediates, thus providing a unique reaction pathway for the reduction of CO2 to CH4. Therefore, under sunlight irradiation, the CH4 selectivity of the catalyst is enhanced to 94.1 % with a production rate of up to 77.8 μmol·g−1·h−1. This work demonstrated the prospect to tune the electronic structure of Pd using rGO, which provided a strategy for enhancing the carbon dioxide reduction reaction and selectively obtaining CH4 products in photocatalytic systems.

Biomass Waste Conversion Technologies for its Utilization and Energy Generation in India: A Perspective

The speedy reduction of fossil fuels and its analogous environmental issues make it necessary for attention to energy generation from alternative fuels. Biomass seems to be one of the likely sources of renewable energy and the computation of waste materials into an appropriate kind of energy, like fuel or electricity, can be completed in several multifarious feasible ways. Utilizing biomass for energy production offers several advantages, including cost-effectiveness, lower sulfur content, and reduced greenhouse gas emissions, contributing to improved environmental sustainability in energy generation processes. This paper takes stock of exploring various biomass conversion technologies for its utilization that can facilitate power generation from biomass waste. It is important to note that biomass utilization extends beyond traditional combustion methods. Latest conversion technologies, including thermal, chemical, and biological processes, have proven to be efficient methods that can replace fossil fuels for producing energy from high-grade sources.

Forest restoration and fuels reduction work: Different pathways for achieving success in the Sierra Nevada.

Fire suppression and past selective logging of large trees have fundamentally changed frequent-fire-adapted forests in California. The culmination of these changes produced forests that are vulnerable to catastrophic change by wildfire, drought, and bark beetles, with climate change exacerbating this vulnerability. Management options available to address this problem include mechanical treatments (Mech), prescribed fire (Fire), or combinations of these treatments (Mech + Fire). We quantify changes in forest structure and composition, fuel accumulation, modeled fire behavior, intertree competition, and economics from a 20-year forest restoration study in the northern Sierra Nevada. All three active treatments (Fire, Mech, Mech + Fire) produced forest conditions that were much more resistant to wildfire than the untreated control. The treatments that included prescribed fire (Fire, Mech + Fire) produced the lowest surface and duff fuel loads and the lowest modeled wildfire hazards. Mech produced low fire hazards beginning 7 years after the initial treatment and Mech + Fire had lower tree growth than controls. The only treatment that produced intertree competition somewhat similar to historical California mixed-conifer forests was Mech + Fire, indicating that stands under this treatment would likely be more resilient to enhanced forest stressors. While Fire reduced modeled wildfire hazard and reintroduced a fundamental ecosystem process, it was done at a net cost to the landowner. Using Mech that included mastication and restoration thinning resulted in positive revenues and was also relatively strong as an investment in reducing modeled wildfire hazard. The Mech + Fire treatment represents a compromise between the desire to sustain financial feasibility and the desire to reintroduce fire. One key component to long-term forest conservation will be continued treatments to maintain or improve the conditions from forest restoration. Many Indigenous people speak of "active stewardship" as one of the key principles in land management and this aligns well with the need for increased restoration in western US forests. If we do not use the knowledge from 20+ years of forest research and the much longer tradition of Indigenous cultural practices and knowledge, frequent-fire forests will continue to be degraded and lost.