Abstract We assess the bulk energy system impact of decarbonizing heavy duty vehicle (HDV) based road transportation via the use of either hydrogen (H2), or drop-in synthetic liquid fuels produced from H2 and CO2. Our analysis soft-links two modeling approaches: a) a bottom-up model of transportation energy demand that produces variety of final energy demand scenarios for the same service demand and b) a multi-sectoral capacity expansion model that co-optimizes power, H2 and CO2 supply chains subjected to technological and policy constraints to meet exogenous final energy demands. Through a case study of Western European countries under deep decarbonization constraints in 2040, we quantify the energy system implications of different levels of H2 and synthetic fuels adoption in the HDV sector under scenarios with and without CO2 sequestration. In the absence of CO2 sequestration, substitution of liquid fossil fuels in HDVs is essential to meet the deep decarbonization constraint across the modeled power, H2 and transport sectors. Additionally, utilizing H2 HDVs reduces total modeled system costs and liquid fuel demand relative to synthetic fuel–based pathways. Synthetic fuel adoption generally increases DAC deployment and associated system costs. The study highlights the trade-offs associated with different transportation decarbonization pathways, and underscores the importance of multi-sectoral considerations in decarbonization studies

Abstract Bio-jet adoption has emerged as an attractive option to complement and supplement the use of refined fossil liquid fuels in the aviation industry in the US. However, there are significant uncertainties surrounding the costs of bio-jet including but not limited to costs of feedstock, transformation costs and the competition with co-products of bio-jet that may be demanded elsewhere in the transportation or energy sectors. This study models alternative trajectories of bio-jet adoption in the US aviation industry by 2050 through the use of a global integrated multi sector dynamics model. Three bio-jet production and consumption pathways are presented- soybean oil to jet, corn ethanol to jet (ETJ) and Fisher–Tropsch-based bio-jet, with each pathway explicitly considering the co-production of renewable diesel and renewable gasoline alongside the bio-jet. Without explicit actions or technology changes to offset the technology cost of bio-jet, scenarios where bio-jet displaces refined liquids result in higher aviation fuel prices (ranging from a 25% increase to 120% increase by mid-century) and lower demand (ranging from −14% to −43%). Corn ethanol will play an important role in the US if large scale amounts of bio-jet are to be produced with smaller effects on demand and prices. While scenarios with high levels of bio-jet availability without the availability of ETJ in the US can significantly reduce emissions in the aviation sector, these reductions are achieved more through the reduction in overall aviation fuel demand rather than technology adoption.

Air pollution causes the premature death of ca. 7 million people each year, with SOx gases being among the most harmful contaminants. Reducing the sulfur content in liquid fossil fuels...

Tracing sources of sedimentary soot: The underestimated role of liquid fossil fuels in North China.

Atmospheric CO 2 represents a crucial greenhouse gas, while in situ observation excluded a full recognition of the spatial scape of such data, and thus prevent a detailed understanding of the specific source contribution to the atmosphere. In this study, we employed a mobile vehicle-based WS-CRDS (wavelength-scanned cavity ring-down spectroscopy) analyzer to conduct continuous measurements of near-surface atmospheric CO 2 concentration and δ 13 C-CO 2 across extensive regions of mainland China during winter, aiming to investigate their spatial patterns, possible driver, and trace emission sources. Our findings reveal distinct spatial heterogeneity in CO 2 concentrations at regional scales. In particular, we observed 53 ppm higher CO 2 concentration in urban areas than in suburban areas, and averaged around 1.35‰ lower δ 13 C to the center of big cities, owing to the increasing CO 2 concentration in association with emission from human activities and depleted carbon isotope from fossil sources. Keeling plot analysis revealed more depleted δ 13 C values in northern cities with around −25.96 ± 2.85‰, than around −24.35 ± 2.87‰ in southern cities, owing to heating practice in northern China. Source δ 13 C comparison indicates that coal and liquid fossil fuels (encompassing gasoline and diesel) constitute the predominant energy sources in most urban areas, representing a key factor influencing the observed winter spatial distribution patterns.

Techno-economic assessment of bio-compressed natural gas as a transport fuel for South African Provinces

The food supply chain’s heavy reliance on electricity poses significant vulnerabilities in the event of prolonged and widespread power disruptions. This study introduces a system-dynamics model that integrates five critical infrastructures—electric grid, liquid fossil fuels, Internet, transportation, and human workforce—to evaluate the resilience of food supply chains to major power outages. We validated the model using the 2019 Venezuelan blackouts as a case study, demonstrating its predictive validity. We then explored how more extreme electricity losses would disrupt the supply chain. More specifically, we modeled the impact of a large-scale cyberattack on the US electric grid and a high-altitude electromagnetic pulse (HEMP) event. A cyberattack severely damaging the US electric grid and allowing for recovery within a few weeks or months would lead to substantial drops in food consumption. However, it would likely still be possible to provide adequate calories to everyone, assuming that food is equitably distributed. In contrast, a year-long recovery from a HEMP event affecting most of the continental United States could precipitate a state of famine. Our analysis represents a first attempt at quantifying how food availability progressively worsens as power outages extend over time. Our open-source model is made publicly available, and we encourage its application to other catastrophic scenarios beyond those specifically considered in this work (for example, extreme solar storms, high-lethality pandemics).

The Chevrel phase compounds Cu4Mo6S8, Ni2Mo6S8, and Fe2Mo6S8, synthesized by self-propagating high temperature synthesis, were evaluated as photocatalysts for visible light photocatalytic desulfurization. Investigations began with reflectance measurements from which absorbance spectra were calculated using the Kubelka-Munk transformation. The absorbance data was then used to create Tauc plots to find the direct and indirect bandgaps of the Chevrel phase compounds. Bandgaps were found to be no more than the 1.74 eV for Ni2Mo6S8, so it was selected for further study because this bandgap suggests it will use the sun's emission spectrum better than the other materials studied here. Photocatalytic desulfurization experiments studied the concentration of thiophene mixed into n-octane with and without exposure to Ni2Mo6S8 with and without light exposure because of the relative difficulty of removing thiophenes from liquid fossil fuels by the industry standard hydrodesulfurization process. Ultraviolet-visible spectroscopy was used to analyze chemical changes in the thiophene-octane solution. Spectroscopic results demonstrate that the thiophene was effectively removed by exposure to Ni2Mo6S8 and visible light together but not by exposure to Ni2Mo6S8 or visible light alone. Multiple tests with the same Ni2Mo6S8 sample demonstrate that the material is reusable as a catalyst for photocatalytic desulfurization. The proposed mechanism results in the release of SO x species, which may be controlled and captured if separated from fossil fuels in bulk during industrial processing in contrast to their uncontrolled release as vehicle fuel exhaust. Controlled generation and collection of these species can allow for further processing into elemental sulfur in the same way that H2S released by standard hydrodesulfurization is processed into elemental S.

Energy production and consumption are key elements of modern economic growth. There is a strong correlation between energy consumption and economic growth [1]. Liquid fossil fuels are a key component of the energy mix, contributing up to 34% of worldwide energy usage [2]. While energy sources are diversifying, liquid fossil fuels are still a key energy source in developing countries such as India. The rapid development of the economy of many countries is expected to intensify the energy demand from fossil fuels. This will inevitably lead to increased CO2 emissions. CO2 emissions have been rising worldwide, reaching 36.3 billion tonnes in 2021 [2]. Annual fossil CO2 emissions are increasing for major GHG emitters in the world. Bloomberg news mentions “Climate change is not a problem with a single solution. And it’s not a challenge that any one group - governments, companies, scientists or individual citizens - can solve alone.” Working together, we can build a healthier and more sustainable future for the generations to come. Utilizing a variety of technologies, e.g., solar, wind, geo-thermal, nuclear, extended batteries, and hydrogen, and strong government support, dedicated companies, universities and research centers, regulatory agencies and others, we have a great opportunity to solve this problem

The Liquid Organic Hydrogen Carrier (LOHC) technology offers a technically attractive way for hydrogen storage. If LOHC systems were to fully replace liquid fossil fuels, they would need to be handled at the multi-million tonne scale. To date, LOHC systems on the market based on toluene or benzyltoluene still offer potential for improvements. Thus, it is of great interest to investigate potential LOHCs that promise better performance and environmental/human hazard profiles. In this context, we investigated the acute aquatic toxicity of oxygen-containing LOHC (oxo-LOHC) systems. Toxic Ratio (TR) values of oxo-LOHC compounds classify them baseline toxicants (0.1 < TR < 10). Additionally, the mixture toxicity test conducted with D. magna suggests that the overall toxicity of a benzophenone-based system can be accurately predicted using a concentration addition model. The estimation of bioconcentration factors (BCF) through the use of the membrane-water partition coefficient indicates that oxo-LOHCs are unlikely to be bioaccumulative (BCF < 2000). None of the oxo-LOHC compounds exhibited hormonal disrupting activities at the tested concentration of 2 mg/L in yeast-based reporter gene assays. Therefore, the oxo-LOHC systems seem to pose a low level of hazard and deserve more attention in ongoing studies searching for the best hydrogen storage technologies.

Hydrogen may become a substitute for liquid fossil fuels, contributing to greenhouse gas emissions reductions in internal combustion engines. Numerical simulations play a critical role in the advancement of these engines, with laminar flame speed being the main input. Experimental data of hydrogen flame speed at elevated pressures are scarce, due to the instability of the flames. Nonetheless, stable hydrogen flames can be predicted using chemical kinetics models. Moreover, the injection of water into the hydrogen fuelled engine could offer several benefits to engine combustion and emission performance, as it modulates the laminar flame speed within the combustion chamber and this effect has not been completely understood. Currently, no correlation exists to predict the laminar flame speed of hydrogen-air combustion with water addition under lean mixture engine operating conditions. In this study, we have extended the newly developed laminar flame speed correlation of hydrogen-air combustion to account for the effects of water addition under engine relevant conditions by using chemical kinetic laminar flame speed values. The laminar flame speed correlation was derived for pressures from 10 to 70 bar, temperatures from 400 to 800 K, equivalence ratios from 0.35 to 1 and water addition by mole from 0 to 20%. The hydrogen laminar flame speed correlation was expressed using polynomial forms with reduced order and number of terms with optimized values of coefficients. Additionally, a new exponential term was proposed to the power term α of the laminar flame speed correlation to capture the coupled effects of pressure and temperature on laminar flame speeds under engine-relevant lean burn water-diluted operating conditions.

Road transport emissions in EDGAR (Emissions Database for Global Atmospheric Research)

Abstract Advanced biofuels have the potential to supplant significant fractions of conventional liquid fossil fuels. However, the range of potential compounds could be wide depending on selected feedstocks and production processes. Not enough is known about the engine relevant behavior of many of these fuels, particularly when used within complex blends. Simulation tools may help to explore the combustion behavior of such blends but rely on robust chemical mechanisms providing accurate predictions of performance targets over large regions of thermochemical space. Tools such as automatic mechanism generation (AMG) may facilitate the generation of suitable mechanisms. Such tools have been commonly applied for the generation of mechanisms describing the oxidation of non‐oxygenated, non‐aromatic hydrocarbons, but the emergence of biofuels adds new challenges due to the presence of functional groups containing oxygen. This study investigates the capabilities of the AMG tool Reaction Mechanism Generator for such a task, using diethyl ether (DEE) as a case study. A methodology for the generation of advanced biofuel mechanisms is proposed and the resultant mechanism is evaluated against literature sourced experimental measurements for ignition delay times, jet‐stirred reactor species concentrations, and flame speeds, over conditions covering φ = 0.5–2.0, P = 1–100 bar, and T = 298–1850 K. The results suggest that AMG tools are capable of rapidly producing accurate models for advanced biofuel components, although considerable upfront input was required. High‐quality fuel specific reaction rates and thermochemistry for oxygenated species were required, as well as a seed mechanism, a thermochemistry library, and an expansion of the reaction family database to include training data for oxygenated compounds. The final DEE mechanism contains 146 species and 4392 reactions and in general, provides more accurate or comparable predictions when compared to literature sourced mechanisms across the investigated target data. The generation of combustion mechanisms for other potential advanced biofuel components could easily capitalize on these database updates reducing the need for future user interventions.

Liquid biofuels are of special interest due to the possibility of their application as a substitute for fossil liquid fuels. The necessary step is to investigate the possibility of bio-fuel application in terms of its properties and similarities to fossil liquid fuels (e.g., crude oil, heavy fuel oil, diesel). The properties and combustion performance of heavy fuel oil (HFO) and products of the fatty acids distillation residues (FADR) were analyzed in this study. The application of animal-fat-delivered fuels is fully suggested in the literature. Nevertheless, the investigations focused on the raw materials or their transformation into diesel. The novelty of this paper is the utilization of FADR as a substitute for HFO. The utilization of FADR allows the use of this material as a feedstock to obtain valuable products (fuel) and avoids generating waste after animal fat processing. The experimental investigations were carried out using a technical-scale 150 kWth combustion chamber. FADR can be recognized as a substitute for HFO due to its beneficial calorific properties and viscosity. Other beneficial effects are the significantly lower emission of SO2 (lower than 1 ppm) and PAHs (i.e., 355 µg/m3n) during the combustion of FADR. Finally, the application of FADR requires less energy demand for fuel heating and pressurization.

Potential natural attenuation of petroleum hydrocarbons in fuel contaminated soils: Focusing on anaerobic fuel biodegradation involving microbial Fe(III) reduction

Hydrogen may become a replacement for liquid fossil fuels, contributing to greenhouse gas emissions reductions by improving the thermal efficiency of boosted lean burn spark ignition engines. Single-zone engine combustion models are simple, but can yield useful results as a step in the design process for developing alternative fuel systems. The single-zone thermodynamic model is advanced by implementing a laminar flame speed sub-model to investigate combustion, an extended Zeldovich mechanism for nitric oxide emissions, and incorporating the Livengood-Wu integral model for knock characteristics. The results were validated using published experiments giving satisfactory predictions between simulation and experiment for spark timing variation, manifold air pressure, and equivalence ratios. A detailed analysis of boosted lean burn strategies showed that nitric oxide emissions increased with boosted pressure, hence emissions can be controlled through optimizing the excess air ratio and the start of combustion. Further techniques to achieve high thermal efficiency and to prevent knock for boosted lean burn hydrogen SI engine are discussed.

Sonoprocessing of oil: Asphaltene declustering behind fine ultrasonic emulsions

To clarify the impact of human activities on the natural environment, as well as the current ecological risks to the environment surrounding Zhushan Bay in Taihu Lake, the characteristics of deposited organic materials, including elements and 16 polycyclic aromatic hydrocarbons (∑16PAHs), in a sediment core from Taihu Lake were determined. The nitrogen (N), carbon (C), hydrogen (H), and sulfur (S) contents ranged from 0.08 to 0.3%, 0.83 to 3.6%, 0.63 to 1.12%, and 0.02 to 0.24%, respectively. The most abundant element in the core was C followed by H, S, and N, while elemental C and the C/H ratio displayed a decreasing trend with depth. The ∑16PAH concentration was in the range of 1807.48-4674.83ngg-1, showing a downward trend with depth, with some fluctuations. Three-ring PAHs dominated in surface sediment, while 5-ring PAHs dominated at a depth of 55-93cm. Six-ring PAHs appeared in the 1830s and gradually increased over time before slowly decreasing from 2005 onward due to the establishment of environmental protection measures. The ratio of PAH monomers indicated that PAHs in samples from a depth of 0 to 55cm were mainly derived from the combustion of liquid fossil fuels, while the PAHs in the deeper samples mainly originated from petroleum. The results of a principal component analysis (PCA) showed that the PAHs in the sediment core of Taihu Lake were mainly derived from the combustion of fossil fuels, such as diesel, petroleum, gasoline, and coal. The contributions of biomass combustion, liquid fossil fuel combustion, coal combustion, and unknown source were 8.99%, 52.68%, 1.65%, and 36.68%, respectively. The results of a toxicity analysis indicated that most of the PAH monomers had little impact on the ecology, and the annual increase of a small number of monomers might have toxic effects on the biological community, resulting in a serious ecological risks, that requires the imposition of control measures.

Given the impact on the environment as well as financial considerations like the gradually rising cost of liquid fossil fuels, maintenance, and other costs, electric vehicles are becoming a more and more appealing option to vehicles with combustion engines. Due to the fact that these cars are well renowned for having zero emissions and being fueled by renewable energy. The project's goal is to replace the current electric motor with an alternate electric vehicle primary mover. Generally speaking, EVs are propelled and controlled by the fusion of electrical, electronic, and mechanical components, but their primary propulsion system is its electric motor. By transforming electrical energy into kinetic energy, an electric motor operates according to the electromagnetic induction theory. An electric motor's primary function is energy conversion, and this actuator is widely used in most EV designs. Therefore, the electric motor will be replaced with a solenoid as the prime mover. A solenoid prototype is created, constructed, and tested for this. A kicking mechanism will be made of the solenoid. A solenoid has been studied as a shooting mechanism in prior investigations. One study looks into the solenoid as the best kicking mechanism. The solenoid was created and optimised in the other investigation. A prototype solenoid is created and tested in this study.

A baseline study of polycyclic aromatic hydrocarbons distribution, source and ecological risk in Zhanjiang mangrove wetlands, South China