Browse Topic: Carbon dioxide

Items (2,350)
The (commercial) aviation sector (passenger and freight), which is strongly engaged with the world efforts to mitigate the carbon emissions and their inherent climate change effects, has accounted in 2018 for 2.4 % of global carbon dioxide (CO2) emissions (pre-pandemic levels). Despite the reductions in air travel demand during the 2020 pandemic, with a reduction of up to 80% in passenger travel during the peak pandemic period, the air travel demand has already recovered to around 80% of the pre-pandemic level, with aviation emissions in 2022 reaching around 800 Mt CO2, accounting for 2% of the global energy related CO2 emissions. Moreover, the demand for air travel is expected to double by 2040, growing at an annual average rate of 3.4%, which means that. despite the efficiency improvement trend (average 2%/year), will almost double the aviation’s greenhouse (GHG) emissions, with a significant increase in its relative GHG share, compared to the other transport modes. Meanwhile the
Barbosa, Fábio Coelho
The aim of this study is to compare possible approaches that support the goal of achieving a carbon-neutral society in the mobility sector, with a specific focus on the two-wheel segment of the mobility sector. One of the key considerations in the mobility sector is the transition from a fossil fuel-based energy mix to a more renewable one. While there are numerous options available for achieving a carbon-neutral society in the four-wheel scenario, the two-wheel sector presents a different challenge due to a smaller number of available options. This study introduces a new comparison between full electric, gasoline, and ethanol-powered two-wheeled vehicles. It suggests that ethanol is a feasible solution for reducing carbon emissions in the two-wheel sector. The study includes an analysis of CO2 emissions for two-wheel vehicles using a life cycle approach, focusing on the technologies of full electric motorcycles, motorcycles with flex-fuel internal combustion engines running on
Pereira, Thaynara K. E.Lima, FlavioUema, Fabio K.Sambuichi, Eduardo M.
In the global scenario marked by the increasing environmental awareness and the necessity on reducing pollutant emission to achieve the decarbonization goals, action plans are being proposed by policy makers to reduce the impact of the climate change, mainly affecting the sectors that most contribute to CO2 emissions such as transportation and power generation. In this sense, by virtue of the National Energy Plan 2050, the Brazilian market will undergo the decommissioning of thermal power plants fueled by diesel and heavy fuel oil (HFO) by 2030, compromising about 6.7 GW of power capacity according to the Brazilian Electricity Regulatory Agency (ANEEL) database. An alternative to the scrapping of these engine power plants is their conversion to operate with fuels with a lower carbon footprint, such as the natural gas. This work, therefore, aims to numerically assess the conversion feasibility of a HFO large bore four-stroke turbocharged engine to operate with natural gas by means of a
Gonçalves, Vinícius FernandezZabeu, Clayton BarcelosAntolini, JácsonSalvador, RobertoAlmeida, RogérioValiati, Allan SoaresFilho, Guenther Carlos Krieger
It is emerging the need to take action to reduce the greenhouse effect, which is one of the major causes of climate change and environmental disasters that has been occurring frequently in recent decades throughout the planet. The burning of fossil fuels for electricity and energy generation are the main concerns and those that have greater incentives for its reduction, as its by-product of the reaction of burning CO2, which among the greenhouse gases is primarily responsible for its aggravation. The transport sector excels in CO2 emissions, emits about 20% of gas, according to the Intergovernmental Panel on Climate Change (IPCC), a scientific organization linked to the United Nations (UN). A promising solution to reduce the impact of this sector would be the use of hydrogen fuel cell, which if carried out through renewable energies, the electrolysis of hydrogen has zero CO2 emission throughout the cycle. However, one of the biggest challenges to make viable the use of hydrogen as fuel
Alves, JoyceSilva, AntônioPaterlini, BrunoSantos, FelipePedroso, HenriqueHenrique, PedroMilani, Pedro
The cumulative accumulation of greenhouse gases (GHGs) historically has resulted in the current problem of global warming. This is further compounded by developed nations, therefore, to fill this gap enhanced global actions are decided. Considering Country’s development need, available resources, government boost for agriculture, A holistic approach for 4W PVs is taken considering well to wheel emissions, as there are other ways to reduce tank to wheel emissions but may not be very effective for overall country’s GHG reduction. Major emissions in vehicle use are calculated based on Carbon intensity of various fuels & optimum pathway for Indian scenario is prepared & discussed in the paper considering all aspects CO2 reduction, development & motorization need. This paper explains multiple pathways for Passenger Vehicle (PV) Sector to be considered to meet country’s GHG needs
Sarna, NishantJaiswal, HarshRani, AbhaDwivedi, VipinVashisth, AjayBhat, AnoopBhat, Anoop
Nestled in the Himalayas, the Kingdom of Bhutan demonstrates a strong commitment to sustainability and environmental conservation, guided by its constitution and the philosophy of Gross National Happiness (GNH). This commitment is underpinned by policies in conservation, waste management, and energy practices. Despite efforts to promote clean energy, Bhutan relies heavily on non-renewable sources—coal, biomass, and petroleum—accounting for 62.4% of its energy mix, while hydropower, wind, and solar contribute 37.6%. The government has introduced initiatives like the “Low Emission Development Strategy” and the “EV Roadmap 2035” to encourage electric vehicle (EV) adoption. However, the transport sector consumes over 108,768.10 KTOE (14.4% of total energy use), with vehicle sales rising at a CAGR of 6.7% from 75,190 in 2014 to 126,650 in 2023. Yet, only 0.36% of these vehicles are electric, while others contributing to 60.01% of the country's carbon dioxide emissions. By referencing
Wangchuk, SingyeDema, Dorji
Incorporating ethanol and biodiesel into diesel fuel offers substantial benefits from bioenergy perspective. To assess the effect of these alternative fuels, a study was undertaken to evaluate the impact of Ethanol-Biodiesel-Diesel blends (BD7, E2B7, E5B7) on the performance and emissions of a diesel car under Modified Indian Driving Cycle (MIDC), Worldwide Harmonized Light Vehicles Test Cycle (WLTC), wide-open throttle (WOT), and acceleration tests. A four-cylinder 1.5L Common Rail Turbo based diesel passenger car was selected for the study. The test findings revealed that under MIDC conditions, biodiesel blend (BD7) resulted in higher CO emissions compared to neat diesel, but these emissions decreased with the addition of ethanol (E2B7 and E5B7) due to ethanol's embedded oxygen content. While biodiesel lowered THC emissions, these emissions increased when ethanol was added. NOx emissions increased with biodiesel due to its higher cetane number and shorter ignition delay, and this
Dhyani, VipinPatil, Yogesh JSinghal, NikitaKhandai, ChinmayanandaKannala, RaghavaMuralidharan, M
Growing demand for fuel-efficient vehicles and lower CO2 emissions has led to the development of lightweight materials. Aluminum composites are being used to achieve lightweighting to improve performance, efficiency, and sustainability across various industries. The unique properties of aluminum composites make them an attractive choice for researchers and designers looking to optimize their products. Reinforcement materials play a vital role in the development of these composites, acting as barriers to dislocation movement within the aluminum matrix. This effectively strengthens the material and prevents deformation under load, resulting in increased tensile strength and fatigue resistance. Additionally, aluminum composites exhibit improved thermal and electrical conductivity, making them suitable for automotive applications. In this study, metal matrix composites (MMCs) of aluminum 7075 alloys were developed using silicon carbide (SiC) and flyash as reinforcements. Three different
Manwatkar, Asmita AshokSantosh Jambhale, MedhaMahagaonkar, NitinSharma, Dipesh
In the last decade, the increased global temperature, stringent regulations, and customer demand for high fuel economy have led to the accelerated development of alternative propulsion solutions, with particular focus on electrified vehicles. Hybrid electric vehicles (HEVs), the combination of electric machinery with conventional powertrains, allows diversifications of powertrain architectures. In addition, it has been demonstrated that engines employing advanced low temperature combustion concepts, such as dual fuel reactivity controlled compression ignition (RCCI), and able to operate on both renewable and conventional fuels, produce ultra-low nitrogen oxides (NOx) and particulate matter (PM) emissions while maintaining thermal efficiency similar to conventional diesel operation at part load operating conditions. This study aims to investigate the potential of integrating a gasoline-diesel RCCI engine in an HEV in achieving reduced fuel consumption and lower NOx and PM emissions
Marwaha, TejasvaKhedkar, Nikhil DilipSarangi, Asish Kumar
R-1234yf is used in almost every new car sold in the U.S., but the EU is discussing a ban and the industry is investigating alternatives like CO2 and propane. According to its manufacturer, Chemours, use of R-1234yf has grown so much since the refrigerant replaced the long-established R-134a that it's now used in 95% of new cars sold in the U.S. An estimated 220 million cars on global roads are also using it. The problem with R-134a, which came in cars and trucks in the 1990s, is that it's a gas with “a global warming potential (GWP) that is 1,430 times that of CO2,” according to the EPA. Since 2017, EU legislation has banned the use of any refrigerant in new vehicles with a GWP higher than 150. That rule doomed R-134a but opened the door for R-1234yf, which has a GWP of only four. The EU is currently revisiting R-1234yf emissions rules and may ban the substance in a few years. In the U.S., the EPA stands by its use
Motavalli, Jim
With advancements in the development of the automated driving technology, vehicles equipped with such technology can be observed widely in market. However, there is a lack of clarity regarding fuel consumption and emission characteristics with automated driving functions. In fact, it cannot be found that any technical papers that have conducted such an evaluation. Therefore, in this study, it was investigated that an evaluation method to understand fuel consumption and emission characteristics by using the adaptive cruise control (ACC) function. The function is one of the automated driving functions which is widely used and corresponds to Level 2 defined by SAE International (Society of Automotive Engineers). In the approach taken for this study, two vehicles were used as the real driving emission test and the preceding vehicle—equipped with a driving robot—was driven accurately to trace the speed pattern defined by the test cycle. The trailing vehicle was driven using the ACC function
Okui, Nobunori
Next generation lubricating oils for transportation sector require higher durability in operation, compatibility with new engine technologies and aftertreatment devices as well as high fuel economy (FE), thus contributing to the reduction of CO2 emissions, both in passenger cars and heavy-duty vehicles. The current paper aims to highlight the impact of dispersant main properties in preventing sludge and deposits formation on engine surfaces. The effect on frictional properties of lubricating oils through a multi-step activity was evaluated. Oil contamination by soot is a big concern not only for diesel but also for new generation of direct injection gasoline (GDI) engines. The presence of soot leads to oil thickening that heavily impacts on friction coefficient thus enhancing the role of dispersant in controlling soot and related viscosity increase and, indirectly, fuel consumption for long running periods. After an introduction on dispersant technologies, the focus of the paper moves
Lattuada, MarcoManni, MassimoNotari, MarcelloFerraro, GiovanniFratini, Emiliano
It is becoming increasingly clear that research into alternative fuels, including drop-in fuels, is essential for the continued survival of the internal combustion engine. In this study, the authors have evaluated olefinic and oxygenated fuels as drop-in fuels using a single-cylinder engine and considering fuel characteristic parameters. The authors have assessed thermal efficiency by adding the EGR amount from 0 to the maximum value that allows stable combustion at the theoretical air-fuel ratio. Next, we attempted to predict fuel efficiency for three types of passenger cars (Japanese small K-car N/A, K-car T/C, and Series-HV) by changing the fuels. We created a model in OpenModelica to estimate fuel efficiency during WLTC driving. The results indicated that fuel economy could potentially be improved by adding an olefin fuel that burns stably even with a large amount of EGR and an oxygen fuel whose octane number increases. It was observed that the fuel economy improvement rate was
Moriyoshi, YasuoKuboyama, TatsuyaKawakami, SotaWang, Zhiyuan
Global warming has intensified environmental challenges such as more intense heat waves due to the accumulation of greenhouse gases, primarily carbon dioxide (CO2), which is heavily produced in power generation and transportation sectors, traps heat and raises the Earth’s temperature. Significant measures must be taken to reduce its production and impact on our environment. Hydrogen (H2) enrichment is a promising technology that enables higher thermal efficiencies and lower exhaust emissions. However, various parameters need to be optimized for internal combustion engines (ICE), which increases experimental and computational costs. The main goal of this work is to offer a reliable correlation that can be used as an input parameter for turbulent combustion models to enhance predictions and lower the cost of running simulations. Thus, the laminar burning velocity (LBV) of binary fuel mixtures is investigated numerically over a wide range of initial conditions (300–600 K and 1–11 atm) and
Almansour, Bader
This SAE Aerospace Information Report (AIR) provides information on air quality and some of the factors affecting the perception of cabin air quality in commercial aircraft cabin air. Also a typical safety analysis process utilizing a Functional Hazard Assessment approach is discussed
AC-9 Aircraft Environmental Systems Committee
Bemis Manufacturing and BASF collaborated to develop a lighter-weight and lower-cost hydraulic tank for compact excavators that was recognized with a lightweighting award traditionally reserved for automotive innovations. Receiving an honorable mention in the Enabling Technology category of this year's Altair Enlighten Awards, the development team leveraged a combination of injection molding and vibration welding techniques to lower costs by approximately 20% and reduce mass by about 5% compared to the traditional roto-molding process. The solution also is more eco-efficient, delivering both environmental savings (reductions in lifecycle CO2 emissions) and reducing lifecycle costs
Gehm, Ryan
Turbulence, temperature changes, water vapor, carbon dioxide, ozone, methane, and other gases absorb, reflect, and scatter sunlight as it passes through the atmosphere, bounces off the Earth’s surface, and is collected by a sensor on a remote sensing satellite. As a result, the spectral data received at the sensor is distorted. Scientists know this and have devised several ways to account for the atmosphere’s corrupting influence on remote sensing data
The Galapagos Islands have a protected marine reserve that currently gets most of its energy—over 80%—from fossil fuels like diesel. This reliance on fossil fuels is a significant issue because it impacts the environment and sustainability of the region. Understanding this heavy dependence is important for exploring alternatives that can provide cleaner energy. This paper introduces a new simulation model based on system dynamics to explore the effects of completely replacing fossil fuels with biodiesel as a short-term solution. The simulation uses current official data for the Galapagos Islands and connects different factors to calculate their effects all at once. Our goal is to identify the social, economic, energy-related, and environmental factors that make biodiesel a better choice than the currently used fossil fuels. We aim to find a way to keep the energy supply stable, as it mainly depends on internal combustion engines, while also quickly providing cleaner and greener energy
Gutierrez, MarcosTaco, Diana
Electrification or hybridization of commercial vehicles offers a promising avenue for mitigating emissions in urban environments. This concept is particularly applicable to waste collection vehicles, which move in urban contexts along repeatedly chosen driving cycles. Municipal waste collection and transport are functional tasks which have a significant impact on the urban environment in terms of energy consumption and CO2 emissions. In this work, the evaluation of a full-electric powertrain was carried out for a small size waste collection vehicle operating in the historic center of the city of Perugia (Italy). First, the vehicle model was developed and validated against literature data using a full-electric powertrain. The model allows to evaluate energy consumption and system efficiency considering the real driving path and the mass variation due to the waste collected during the route. Real driving data (position, slope, collection stops) were obtained through an experimental
Zembi, JacopoBistoni, LorenzoCinti, GiovanniCastellani, BeatriceBattistoni, Michele
Abstract As an important contributor to greenhouse gas emissions, the road freight sector plays a significant role when it comes to reaching global climate goals. Due to the requirements regarding payloads and ranges, the transition towards zero emissions is particularly challenging in this sector. A technical solution that can contribute to the reduction of greenhouse gas emissions are electrified semi-trailer systems. These vehicles can be combined with conventional tractor vehicles in order to reduce their fuel consumption and CO2 footprint, as well as with tractor vehicles with alternative powertrains to increase their driving range. In this paper, a simulation study that evaluates the potentials of different configurations for such a system is performed. In the first part the general working principle of an electrified trailer is described. This includes a cloud based predictive energy management system that was used during the simulations. Based on a general vehicle model, the
Knaup, LarsBeidl, Christian
Since signing the legally binding Paris agreement, fighting climate change has been an increasingly important task worldwide. One of the key energy sectors to emit greenhouse gases is transportation. Therefore, long term strategies all over the world have been set up to reduce on-road combustion emissions. One of the emerging alternative technologies to decarbonize the transportation sector is Mobile Carbon Capture (MCC). MCC refers to the on-board separation of CO2 from vehicle exhaust. To accurately assess this technology, a techno-economic analysis is essential to compare MCC abatement cost to alternative decarbonization technologies such as electric trucks. Adding to the system capital and operational costs, our study includes mass penalty costs, CO2 offloading and transport costs for different transport scenarios. To better relate to a single consumer (driver), the cost can be converted from euro per-tCO2 to euro per-trip or euro per-mile. A sensitivity analysis is then conducted
SAAFI, Mohamed AliHamad, Esam
Decarbonization and a continuous reduction in exhaust emissions from combustion engines are key objectives in the further development of modern powertrains. In order to address both aspects, the DE4LoRa research project is developing an innovative hybrid powertrain that is characterized by the highly flexible combination of two electric motors with a monovalent compressed natural gas (CNG) engine. This approach enables highly efficient driving in purely electric, parallel and serial operating modes. The use of synthetic CNG alone leads to a significant reduction in CO2 emissions and thus in the climate impact of the drivetrain. With CNG-powered engines in particular, however, methane and other tailpipe emissions of climate gases and pollutants must also be minimized. This is possible in particular through efficient exhaust gas aftertreatment and an effective operating strategy of the powertrain. This publication presents measurement results that examine the critical aspect of cold
Noone, PatrickHerold, TimBeidl, Christian
Even if huge efforts are made to push alternative mobility concepts, such as, electric cars (BEV) and fuel cell powered cars, the importance and use of liquid fuels is anticipated to stay high during the 2030s. The biomethane and synthetic natural gas (SNG) might play a major role in this context as they are raw material for chemical industry, easy to be stored via existing infrastructure, easy to distribute via existing infrastructure, and versatile energy carrier for power generation and mobile applications. Hence, biomethane and synthetic natural gas might play a major role as they are suitable for power generation as well as for mobile applications and can replace natural gas without any infrastructure changes. In this paper, we aim to understand the direct production of synthetic natural gas from CO2 and H2 in a Sabatier process based on a thermodynamic analysis as well as a multi-step kinetic approach. For this purpose, we thoroughly discuss CO2 methanation to control emission in
Mauss, Fabian
Fighting climate change has become a major task worldwide. Alongside the United States and China, Europe is considered as one of the biggest greenhouse gases (GHG) emitters. Therefore, the European Union (EU) has set long term strategies to reduce emissions. One of the key energy sectors to emit greenhouse gases is transportation. In this context, EU has turned its eye toward cutting emissions from the transport sector and has recently put its stamp of approval on a reworked law banning all new sales of internal combustion engine (ICE) vehicles from 2035. Despite representing only 2% of the vehicles on the road, trucks account for more than a quarter of road transport emissions in the EU and have been increasing every year since 1990. In order to investigate the impact of transportation projected policies on the heavy-duty sector, we develop the Mobility and Energy Transportation Analysis (META) Model, a python-based model to project market penetration of conventional and alternative
SAAFI, Mohamed Ali
Cars and vans are accountable for 14.5% of the total CO2 emissions in the European Union, exerting a significant impact on public health and the environment. To align with the climate objectives set by the Council and the European Parliament, the Fit for 55 package encompasses a series of proposals aimed at revising and modernizing EU legislation while introducing new initiatives. The ultimate goal is to ensure that EU policies are in harmony with the climate targets, specifically the EU’s aspiration to reduce greenhouse gases (GHGs) by at least 55% by 2030 compared to 1990 levels and achieve climate neutrality by 2050. To meet the fleet average emissions targets, automotive Original Equipment Manufacturers (OEMs) are compelled to reduce emissions from their vehicles by addressing various components. The urgent need for car makers to reduce their carbon footprint, combined with the imperative to improve the mileage range of electric vehicles, has led to the creation of a novel
Bogliacino, FabioRe, PaoloFerrero, Alessandro
A bearing is a mechanical component that transmits rotation and supports load. Depending on the type of rotating mechanism, bearings are categorized into ball bearings and tapered-roller bearings. Tapered-roller bearings are superior to ball bearings in load-bearing capabilities. They are used in applications where high loads, such as, the wheel bearings for commercial vehicles and trucks, aircraft, high-speed trains, and heavy-duty spindles for heavy machinery must be supported. The demand for reducing the friction torque in automobiles has recently increased owing to carbon-emission regulations and fuel-efficiency requirements. Therefore, research on the friction torque of bearings is essential; studies have been conducted on lubrication, friction, and contact in tapered-roller bearings. There have also been studies on lip friction, roller misalignment, and so on; however, research on the influence of roller geometries and material properties is scarce. This study investigated the
Lee, SeungpyoAn, Hyun Gyu
Methanol, as a renewable fuel, is an attractive option for internal combustion engines. The dual direct injection method is one of the most promising strategies for applying methanol fuel in diesel engines as the flexible injection control enables combustion mode switching. In this study, a 1-L single-cylinder common-rail diesel engine with a compression ratio of 17.4 is retrofitted by installing an additional methanol direct injector with 35 MPa injection pressure. The engine is operated at 1400 rpm, intermediate load, and fixed midpoint combustion phasing of 10 °CA aTDC with a fixed total amount of energy while applying an energy substitution principle with up to 70% energy supplied by methanol. From the experiments, three distinct combustion modes were identified. When early methanol injection timings were selected in the range of 180–60 °CA bTDC, the primary combustion mode was premixed burn. Late injection timings of 10 °CA bTDC to TDC led to heat release rate shapes of the
Zhao, YifanLiu, XinyuKook, Sanghoon
Solar panels are an increasingly popular way to generate electricity from the sun’s energy. Although humans are still figuring out how to reliably turn that energy into fuel, plants have been doing it for eons through photosynthesis. Now, a team reporting in ACS Engineering Au has mimicked the process to produce methane, an energy-dense fuel, from carbon dioxide, water and sunlight. Their prototype system could help pave the way toward replacing nonrenewable fossil fuels
Heavy-duty vehicle regulations from the European Union specify a 43% carbon emissions reduction by 2030. The EU's carbon emissions reduction mandate climbs to 64% by 2035 before soaring to 90% by 2040. “The hydrogen combustion engine has a role to play to reduce CO2 emissions,” said Vincent Giuffrida, CFD engineer for IFP Energies novellas (IFPEN), a Rueil-Malmaison, France-headquartered public research and innovation organization. Giuffrida and IFPEN colleague and research engineer Olivier Colin were the presenters for a webinar addressing the “Development of a Dedicated Hydrogen Combustion System for Heavy-Duty Applications” in July. The webinar was hosted by Madison, Wisconsin-headquartered Convergent Science, whose CONVERGE CFD software simulates three-dimensional fluid flows. Features of the CFD software include autonomous meshing, complex moving geometries, a detailed chemical kinetics solver, advanced physical models, conjugate heat transfer model, fluid structure interaction
Buchholz, Kami
Even as the world slowly begins to decarbonize industrial processes, achieving lower concentrations of atmospheric carbon requires technologies that remove existing carbon dioxide from the atmosphere — rather than just prevent the creation of it
Researchers at the Department of Energy’s Oak Ridge National Laboratory are developing battery technologies to fight climate change in two ways, by expanding the use of renewable energy and capturing airborne carbon dioxide
The heavy-duty off-road industry continues to expand efforts to reduce fuel consumption and CO2e (carbon dioxide equivalent) emissions. Many manufacturers are pursuing electrification to decrease fuel consumption and emissions. Future policies will likely require electrification for CO2e savings, as seen in light-duty on-road vehicles. Electrified architectures vary widely in the heavy-duty off-road space, with parallel hybrids in some applications and series hybrids in others. The diverse applications for different types of equipment mean different electrified configurations are required. Companies must also determine the value in pursuing electrified architectures; this work analyzes a range of electrified architectures, from micro hybrids to parallel hybrids to series hybrids to a BEV, looking at the total cost, total CO2e, and cost per CO2e (cost of carbon abatement, or cost of carbon reduction) using data for the year 2021. This study is focused on a heavy-duty off-road material
Goodenough, BryantCzarnecki, AlexanderRobinette, DarrellWorm, JeremyBurroughs, BrianLatendresse, PhilWestman, John
Engine and aftertreatment solutions have been identified to meet the upcoming ultra-low NOx regulations on heavy duty vehicles in the United States. These standards will require changes to current conventional aftertreatment systems for dealing with low exhaust temperature scenarios while increasing the useful life of the engine and aftertreatment system. Previous studies have shown feasibility of meeting the US EPA and California Air Resource Board (CARB) requirements. This work includes a 15L diesel engine equipped with cylinder deactivation (CDA) and an aftertreatment system that was fully DAAAC aged to 800,000 miles. The aftertreatment system includes an e-heater (electric heater), light-off Selective Catalytic Reduction (LO-SCR) followed by a primary aftertreatment system containing a DPF and SCR. The e-heater was capable of providing up to 10 kW, however for the purpose of this project, lower power settings of 2.5 kW and 5 kW were studied in combination with CDA for lowest
Kramer, JanRice, MichaelZavala, BryanSharp, ChristopherMcCarthy, JamesKarrer, Ben
With the COP28 decisions the world is thriving for a future net-zero-CO2 society and the and current regulation acts, the energy infrastructure is changing in direction of renewables in energy production. All industry sectors will extend their share of direct or indirect electrification. The question might arise if the build-up of the renewables in energy production is fast enough. Demand and supply might not match in the short- and mid-term. The paper will discuss the roadmaps, directions and legislative boundary parameter in the regenerative energy landscape and their regional differences. National funding on renewables will gain an increasing importance to accelerate the energy transformation. The are often competing in attracting the same know-how on a global scale. In addition the paper includes details about energy conversion, efficiency as well as potential transport scenarios from production to the end consumer. Technologies are compared in respect of their TLR level and
Rothbart, Martin
EU legislation provides for only local CO2 emission-free vehicles to be allowed in individual passenger transport by 2035. In addition, the directive provides for fuels from renewable sources, i.e. defossilised fuels. This development leads to three possible energy sources or forms of energy for use in individual transport. The first possibility is charging with electricity generated from renewable sources, the second possibility is hydrogen generated from renewable sources or blue production path. The third possibility is the use of renewable fuels, also called e-fuels. These fuels are produced from atmospheric CO2 and renewable hydrogen. Possible processes for this are, for example, methanol or Fischer-Tropsch synthesis. The production of these fuels is very energy-intensive and large amounts of renewable electricity are needed. Thus, national production of these fuels in the EU is inefficient in terms of cost and carbon footprint due to the low utilisation rate of renewable energy
Stoll, TobiasKulzer, AndreBerner, Hans-Juergen
Society is moving towards climate neutrality where hydrogen fuelled combustion engines (H2 ICE) could be considered a main technology. These engines run on hydrogen (H2) so carbon-based emission are only present at a very low level from the lube oil. The most important pollutants NO and NO2 are caused by the exhaust aftertreatment system as well as CO2 coming from the ambient air. For standard measurement technologies these low levels of CO2 are hard to detect due to the high-water content. Normal levels of CO2 are between 400-500 ppm which is very close or even below the detection limit of commonly used non-dispersive-infrared-detectors (NDIR). As well the high-water content is very challenging for NOx measuring devices, like chemiluminescence detectors (CLD), where it results in higher noise and therefore a worse detection limit. Even for Fourier-transformed-infrared-spectroscopy-analysers (FT-IR) it is challenging to deal with water content over 15% without increased noise. The goal
Jakubec, PhilippRoiser, Sebastian
The fast acceleration of GHG (CO2 in particular) emitted by human activities into the atmosphere is accelerating the average temperature increase of our globe causing heavy climate change. This phenomenon has triggered a strong pressure on GHG emission reduction in all the human activities including the transportation sector which contributes for the 29% to the total emissions in EU [1]. A mitigation to this tendency can come from synthetic fuels: when produced by using clean energy, they can be considered CO2 neutral. H2 is the building block of synthetic fuels and can be used in spark ignited engines where releases the energy accumulated during its production. This solution is particularly attractive for HD applications thanks to the high energy density. H2 can be burned in a quite wide range of λ, but staying on 2,2 the amount of engine out NOx will be low enough for the use on a 13L engine with a relatively simple aftertreatment system. This λ value is difficult to maintain in the
Andrisani, NicolaBagal, Nilesh
Fossil fuels such as natural gas used in engines still play an important role worldwide which however is also exacerbating climate change as a result of carbon dioxide emissions. Although natural gas engines show an overall low pollutant emissions level, methane slip due to incomplete combustion occurs, causing methane emissions with a more than 20 times higher global warming potential than CO2. Additionally, further tightening of emissions legislation is to be expected bringing methane emissions even more into focus making exhaust gas aftertreatment issues remain relevant. For lean gas applications, (Pd)-based catalysts turned out to convert CH4 most efficiently usually being supported by metal oxides such as aluminium oxide (Al2O3). Water (H2O) contained in the exhaust gas causes strong inhibition on Pd catalysts. In real exhaust gases, not only water vapour but also pollutants and sulphur-containing compounds such as hydrogen sulphide (H2S) or sulphur oxides (SOx) are poisoning the
Tomin, SebastianWagner, UweKoch, Thomas
The global transportation industry, and road freight in particular, faces formidable challenges in reducing Greenhouse Gas (GHG) emissions; both Europe and the US have already enabled legislation with CO2 / GHG reduction targets. In Europe, targets are set on a fleet level basis: a CO2 baseline has already been established using Heavy Duty Vehicle (HDV) data collected and analyzed by the European Environment Agency (EEA) in 2019/2020. This baseline data has been published as the reference for the required CO2 reductions. More recently, the EU has proposed a Zero Emissions Vehicle definition of 3g CO2/t-km. The Zero Emissions Vehicle (ZEV) designation is expected to be key to a number of market instruments that improve the economics and practicality of hydrogen trucks. This paper assesses the permissible amount of carbon-based fuel in hydrogen fueled vehicles – the Pilot Energy Ratio (PER) – for each regulated subgroup of HDVs in the baseline data set. The analysis indicates that a PER
Mumford, David K.Williams, GrahamLeclercq, Nadege
For battery-electric vehicles (BEVs), the climate control and the driving range are crucial criteria in the ongoing electrification of automobiles in Europe towards the targeted carbon neutrality of the automotive industry. The thermal management system makes an important contribution to the energy efficiency and the cabin comfort of the vehicle. In addition to the system architecture, the refrigerant is crucial to achieve high cooling and heating performance while maintaining high efficiency and thus low energy consumption. Due to the high efficiency requirements for the vehicle, future system architectures will largely be heat pump systems. The alternative refrigerant R-474A based on the molecule R-1132(E) achieved top performance for both parameters in various system and vehicle tests. An own-built energy efficiency tool was used to determine the possible energy reduction of R-474A in comparison to refrigerant alternatives that can be translated in a CO2 reduction of the thermal
Macrì, ChristianDe León, ÁlvaroFlohr, Felix
The escalating energy demand in today’s world has amplified exhaust emissions, contributing significantly to climate change. One viable solution to mitigate carbon dioxide emissions is the utilization of hydrogen alongside gasoline in internal combustion engines. In pursuit of this objective, combustion characteristics of iso-octane/hydrogen/air mixtures are numerically investigated to determine the impact of hydrogen enrichment. Simulations are conducted at 400 K over a wide range of equivalence ratio 0.7 ≤ Ф ≤ 1.4 and pressure 1–10 atm. Adiabatic flame temperature, thermal diffusivity, laminar burning velocity, and chemical participation are assessed by varying hydrogen concentration from 0 to 90% of fuel molar fraction. As a result of changes in thermal properties and chemical participation, it is noticed that the laminar burning velocity (LBV) increases with higher hydrogen concentration and decreases as pressure increases. Chemical participation and mass diffusion were found to be
Almansour, Bader
The transportation sector’s growing focus on addressing environmental and sustainable energy concerns has led to a pursuit of the decarbonization path. In this context, hydrogen emerges as a promising zero-carbon fuel. The ability of hydrogen fuel to provide reliable performance while reducing environmental impact makes it crucial in the quest for net zero targets. This study compares gasoline and hydrogen combustion in a single-cylinder boosted direct injection (DI) spark ignition engine under various operating conditions. Initially, the engine was run over a wide range of lambda values to determine the optimal operating point for hydrogen and demonstrate lean hydrogen combustion’s benefits over gasoline combustion. Furthermore, a load sweep test was conducted at 2000 rpm, and the performance and emission results were compared between gasoline and optimized hydrogen combustion. An in-depth analysis was conducted by varying fuel injection time and pressure. This enabled us to explore
Mohamed, MohamedBiswal, AbinashWang, XinyanZhao, HuaHarrington, AnthonyHall, Jonathan
Most heavy trucks should be fully electric, using a combination of batteries and catenary electrification, but heavy trucks requiring very long unsupported range will need chemical fuels. Hydrogen is the key to storing renewably generated electricity chemically. At the scale of heavy trucks, compressed hydrogen can match the specific energy of diesel, but its energy density is five times lower, limiting the range to around 2,000 km. Scaling green hydrogen production and addressing leakage must be priorities. Hydrogen-derived electrofuels—or “e-fuels”—have the potential to scale, and while the economic comparison currently has unknowns, clean air considerations have gained new importance. The limited supply of bioenergy should be reserved for critical applications, such as bioenergy with carbon capture and storage (BECCS), aviation, shipping, and road freight in the most remote locations. Additionally, there are some reasons to prefer ethanol or methanol to diesel-type fuels as they are
Muelaner, Jody E.
Carbon capture is a critical technology in reducing greenhouse gas emissions from power plants and other industrial facilities. But a suitable material for effective carbon capture at low cost has yet to be found. One candidate is metal-organic frameworks, or MOFs. This porous material can selectively absorb carbon dioxide
Researchers at the U.S. Department of Energy’s (DOE) Brookhaven National Laboratory and Columbia University have developed a way to convert carbon dioxide (CO2), a potent greenhouse gas, into carbon nanofibers, materials with a wide range of unique properties and many potential long-term uses. Their strategy uses tandem electrochemical and thermochemical reactions run at relatively low temperatures and ambient pressure. As the scientists describe in the journal Nature Catalysis, this approach could successfully lock carbon away in a useful solid form to offset or even achieve negative carbon emissions
Vehicle emissions, which are rising alarmingly quickly, are a significant contributor to the air pollution that results. Incomplete combustion, which results in the release of chemicals including carbon monoxide, hydrocarbons, and particulate matter, is the main cause of pollutants from vehicle emissions. However, CO2 contributes more than the aforementioned pollutants combined. Carbon dioxide is the main greenhouse gas that vehicles emit. For every liter of gasoline burned by vehicles, around 2,347 grams of carbon dioxide are released. Therefore, it’s important to reduce vehicle emissions of carbon dioxide. The ability of materials like zeolite and silicon dioxide to absorb CO2 is outstanding. These substances transform CO2 into their own non-polluting carbonate molecules. Zeolite, silicon dioxide, and calcium oxide are combined to form the scrubbing material in a ratio based on their increasing adsorption propensities, along with enough bentonite sand to bind the mixture
Saravanakumar, L.Arunprasad, S.
The abatement of carbon dioxide and pollutant emissions on motorbike spark-ignition (SI) engines is a challenging task, considering the small size, the low cost and the high power-to-weight ratio required by the market for such powertrain. In this context, the passive pre-chamber (PPC) technology is an attractive solution. The combustion duration can be reduced by igniting the air-fuel mixture inside a small volume connected to the cylinder, unfolding the way to high engine efficiencies without penalization of the peak performance. Moreover, no injectors are needed inside the PPC, guaranteeing a cheap and fast retrofitting of the existing fleet. In this work, a 3D computational fluid dynamics (CFD) investigation is carried out over an experimental configuration of motorbike SI engine, operated at fixed operating conditions with both traditional and PPC configurations. The employed CFD methodology is based on a unique flamelet-based combustion model, regardless the selected ignition
Nodi, AlessandroSforza, LorenzoLucchini, TommasoOnorati, AngeloButtitta, MarcoMarmorini, Luca
The LCA (Life Cycle Assessment) methodology is nowadays considered fundamental for the estimation and analysis of the economic and social impacts coming from the CO2 (Carbon Dioxide) footprint. It is a methodology for evaluating the “environmental footprint” of the product, “from cradle to grave” and it is carried out by quantifying the impacts deriving from both the use of resources and emissions into the environment. The aim of this study is to contribute to environmental assessment in the context of the sustainability of vehicular transport in urban areas. For this reason, through a comparative analysis of the LCA it is possible to evaluate the CO2 emissions deriving from cars during real use and relating to the entire life of the vehicles. Three comparisons were made considering pairs made up of an electric vehicle and an internal combustion vehicle of the same segment and category: small city cars, mid-size and SUV. In the development of the work, various articles have been
Meccariello, GiovanniDella Ragione, Livia
Soot and carbon dioxide released from internal combustion engines became the key issues when using fossil fuels. Ammonia and hydrogen having zero-carbon species can reduce carbon-related emissions and enhance the reliance on renewable fuels. A comparative study of ammonia and hydrogen impact on combustion and emission characteristics of iso-octane flame was performed under different combustion conditions. Arrhenius equation, soot surface reactions, and modified kinetic mechanism were used to study the flame growth, soot nucleation, and surface growth rates. The results show that hydrogen increased the temperature about 20.74 K and 59.30 K, whereas ammonia reduced it about 82.17 K and 66.03 K at premixed and counterflow conditions, respectively. The flame speed of iso-octane was increased 43.83 cm/s by hydrogen and decreased 34.36 cm/s by ammonia. A reduction in CH2O caused a reduction in CO and CO2 emissions. Ammonia impact on CO reduction was stronger than hydrogen under premixed and
Akram, M. ZuhaibRashid, HaroonDeng, YangboAziz, MuhammadZhu, QiaoAkram, M. Waqar
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