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A hydrogen concentration from ethanol-gasoline blends reforming processes plays a role in exhausted gas recirculation (EGR) that enhanced engine performance and aftertreatment system of gasoline direct injection (GDI) engine. An equilibrium model is widely used as a primary tool to determine a level of hydrogen content from reforming process. Thus, in this work, the equilibrium analysis of hydrogen production is investigated using STANJAN program. Three main reactions (Partial Oxidation Reforming (POx), steam reforming (SRM) and autothermal reforming (ATR)) are studied here. Three commercial ethanol-gasoline blends are studies here (E10, E20 and E85). The effect of reaction temperature, steam to fuel ratio (S/F) and oxygen to fuel ratios (O2/F) are investigated. The results show that the optimum condition for POx is achieved at O2/F ratio of 3 for E10 and E20 and 0.75 for E85. For SRM, the optimum condition for H2 production at temperature 200–500 °C are achieved with S/F ratio of 10–12 for E10 and E20, while E85 can be obtained at S/F ratio of 6–8. Under these conditions, the maximum hydrogen yield (∼30 vol%) are reached with temperature 500 °C. In case of ATR, the highest H2 yield (approximately 25 vol%) is achieved at temperature 500 °C with S/F ratio of 8 for E10 and E20 fuels and 4 for E85 fuel. The highest H2 yields from real exhausted gas reforming are 42 to 55 % vol. Thus, this possibility of on-board hydrogen production via gasoline - ethanol fuel blends reforming operates in GDI engine.

Based on the results obtained in the project it can be stated that PHEVs could provide an effective additional measure for reducing CO2 emissions in typical Finnish daily trips where 93% of daily mileage is less than 50 km. Results showed that PHEVs are capable of covering the typical Finnish daily mileage fully electrically in different driving conditions. However, results also showed that the electric range drops greatly when the ambient temperature decreases below roughly 5 °C. If a PHEV is used with an empty battery, CO2 emissions are well above the officially declared values. On the commuter test route where the test started with an empty battery, PHEVs produced 5% to 66% higher CO2 emissions depending on the PHEV compared to a diesel car. However, on the city test route, two of the PHEVs were in best case capable of diesel car-like CO2 emissions when the test was started with an empty battery. The NOx emissions of the tested PHEVs, diesel car and van were at a low level, even well below the regulatory limit values. Overall, PHEVs performed the best, producing NOx emissions mostly below 0.01 g/km, corresponding to a conformity factor (CF) value of 0.17 and below. There was no observed significant increase in NOx emissions during the change of propulsion from electric drive to ICE drive, even in sub-zero Celsius temperatures. The NOx emissions of the diesel car were also well below the legislative limit value. Emissions varied between 0.005 g/km to 0.092 g/km depending on test route and ambient conditions; these correspond to CF values of between 0.063 to 1.15. The ambient temperature had a clear effect on NOx emissions, as an increasing trend was observed as a function of decreasing ambient temperatures. A van was tested on a test route replicating a typical delivery journey in a suburban area. NOx emissions were 0.05 g/km when start-stop functionality was deactivated, and 0.065 g/km when it was activated. These figures correspond to CF values of 0.40 and 0.52. NOx emission performance was also tested against the proposed limit values of Euro 7 regulation. PHEVs were capable of meeting the limit values with clear margins. The diesel car greatly exceeded the proposed limit values on cold start routes. However, it did meet the limit values in warm start tests. NOx emissions from the van were close to the limit value and in some tests, they were below the limit. In general, PN emissions were well below the regulatory limit values in every test condition with all tested vehicles. In summary, it can be stated that the tested vehicles are capable of low NOx and PN emissions in different driving and ambient conditions. In addition, PHEVs with renewable fuels like high ethanol fuels (E85) could provide effective additional measures for reducing CO2 emissions among BEVs. Especially on short trips, regularly charged PHEVs provide close to BEV energy consumption and thus CO2 emissions. For longer distances, renewable fuels would ensure a low carbon footprint. To achieve regular charging all incentives that discourage the user to charge the battery regularly should be removed.

Based on the results obtained in the project it can be stated that PHEVs could provide an effective additional measure for reducing CO2 emissions in typical Finnish daily trips where 93% of daily mileage is less than 50 km. Results showed that PHEVs are capable of covering the typical Finnish daily mileage fully electrically in different driving conditions. However, results also showed that the electric range drops greatly when the ambient temperature decreases below roughly 5 °C. If a PHEV is used with an empty battery, CO2 emissions are well above the officially declared values. On the commuter test route where the test started with an empty battery, PHEVs produced 5% to 66% higher CO2 emissions depending on the PHEV compared to a diesel car. However, on the city test route, two of the PHEVs were in best case capable of diesel car-like CO2 emissions when the test was started with an empty battery. The NOx emissions of the tested PHEVs, diesel car and van were at a low level, even well below the regulatory limit values. Overall, PHEVs performed the best, producing NOx emissions mostly below 0.01 g/km, corresponding to a conformity factor (CF) value of 0.17 and below. There was no observed significant increase in NOx emissions during the change of propulsion from electric drive to ICE drive, even in sub-zero Celsius temperatures. The NOx emissions of the diesel car were also well below the legislative limit value. Emissions varied between 0.005 g/km to 0.092 g/km depending on test route and ambient conditions; these correspond to CF values of between 0.063 to 1.15. The ambient temperature had a clear effect on NOx emissions, as an increasing trend was observed as a function of decreasing ambient temperatures. A van was tested on a test route replicating a typical delivery journey in a suburban area. NOx emissions were 0.05 g/km when start-stop functionality was deactivated, and 0.065 g/km when it was activated. These figures correspond to CF values of 0.40 and 0.52. NOx emission performance was also tested against the proposed limit values of Euro 7 regulation. PHEVs were capable of meeting the limit values with clear margins. The diesel car greatly exceeded the proposed limit values on cold start routes. However, it did meet the limit values in warm start tests. NOx emissions from the van were close to the limit value and in some tests, they were below the limit. In general, PN emissions were well below the regulatory limit values in every test condition with all tested vehicles. In summary, it can be stated that the tested vehicles are capable of low NOx and PN emissions in different driving and ambient conditions. In addition, PHEVs with renewable fuels like high ethanol fuels (E85) could provide effective additional measures for reducing CO2 emissions among BEVs. Especially on short trips, regularly charged PHEVs provide close to BEV energy consumption and thus CO2 emissions. For longer distances, renewable fuels would ensure a low carbon footprint. To achieve regular charging all incentives that discourage the user to charge the battery regularly should be removed.

Transportation should become sustainable and available to everyone. Currently, transportation accounts for approx. one sixth of greenhouse gas (GHG) emissions globally, and heavy-duty trucks are responsible for almost 30% of that. When fossil diesel fuel is burned in a compression ignition engine, known as a diesel engine, it releases large amounts of CO2, a GHG, into the air. GHGs confine heat in our atmosphere, causing global warming. Furthermore, the emissions are polluting air locally, having negative impact on human health and nature, but also some are adding to the global warming effects. Renewable diesel-like fuels, RME (rapeseed oil methyl ester) and HVO (hydrotreated vegetable oil), and light renewable or less carbon-intense alcohols, methanol and ethanol, as well as blended fuel E85 (ethanol and gasoline), can be used to reduce net CO2 emissions, particulate matter (PM) and gaseous pollutants from the engine. They are available on the market and can be fed to diesel engines without major hardware modifications or by using the available technology. The aim of this PhD thesis was to investigate the effect of replacing fossil diesel fuel with renewable fuels, on the performance and local exhaust emissions of a heavy-duty diesel engine.In experimental studies, particle size distributions in the exhaust were compared to those of fossil diesel. The origin of PM from these less-sooting fuels was studied. The compositions of organic aerosol (OA) and secondary organic aerosol (SOA) from HVO, RME and fossil diesel were analyzed, and the effect of a diesel oxidation catalyst (DOC) was evaluated. Formation of SOA in the atmosphere was simulated by aging emissions in an oxidation flow reactor. The nanostructure of the soot when operating on RME, diesel, methanol or ethanol was studied. Finally, the viability of using E85 fuel in a production truck engine was tested.Ethanol and methanol proved to be nearly non-sooting fuels, with the nanoparticles in the exhaust originating primarily from the lubrication oil. The engine performed well with E85 fuel, with almost all raw emissions below the current legislated levels for one operation setting.PM emissions were significantly lower when fossil diesel was replaced with HVO or RME. The chemical composition of OA was likely dominated by lubrication oil for all three diesel-like fuels. RME reduced both the OA emissions and changed the composition with evidence for minor fuel contributions in the mass spectra. The unregulated nanoparticles of size between 5 nm and 23 nm, which are also thought to originate from the lubrication oil, were emitted in high numbers as nucleation mode. RME and diesel branched soot agglomerates were composed of several tens to hundreds of primary particles, and diesel soot also contained fly ashes from burned engine lubrication oil. SOA formation was substantially lower for RME compared to fossil diesel and HVO. The DOC strongly reduced primary organic emissions in both the gas (hydrocarbons) and particle phase (OA), and only 12 marginally affected OA composition. The DOC was also effective in reducing SOA formation upon atmospheric aging.In order to defossilize transportation, all available technology and research efforts need to get united. When it comes to the heavy-duty sector, the most straightforward solution would be to replace fossil diesel fuel with a diesel-like fuel of non-fossil origin, beginning with the existing vehicle fleets. The use of HVO, RME and light alcohols would have a positive impact on an overall PM reduction.

A commercially available fuel, E85, a blend of ~85% ethanol and ~15% gasoline, can be a viable substitute for fossil fuels in internal combustion engines in order to achieve a reduction of the greenhouse gas (GHG) emissions. Ethanol is traditionally made of biomass, which makes it a part of the food-feed-fuel competition. New processes that reuse waste products from other industries have recently been developed, making ethanol a renewable and sustainable second-generation fuel. So far, work on E85 has focused on spark ignition (SI) concepts due to high octane rating of this fuel. There is very little research on its application in CI engines. Alcohols are known for low soot particle emissions, which gives them an advantage in the NOx–soot trade-off of the compression ignition (CI) concept. Therefore, the main objective of this research is to experimentally characterise the impact of E85 on performance and emissions of a heavy-duty (HD) direct ignition compression ignition (DICI) engine at mid-to-low load, and to identify possible challenges. To do so, a surface response method of the Box-Behnken type is implemented on a measurement campaign on a HD single cylinder CI engine. The effects of common rail pressure (Prail), λ and combustion timing (CA50) as control parameters on experimentally measured values of soot, regulated gaseous emissions (NOx, CO and THC) and gross indicated efficiency (GIE) of the engine are studied. Linear regression (LR) analysis indicates that the outputs of the NOx and soot models are affected by all three control parameters, whereas GIE, THC and CO models in this case exclude λ effects. E85 fuel shows potential to be a good candidate for highly efficient low temperature combustion (LTC) in DICI engines, with reduced NOx and soot levels compared to fossil diesel combustion.

In this study, the impact of engine control parameters on combustion behaviors and particle number emissions was investigated with a spark ignition direct injection (SIDI) engine used various gasoline-ethanol blended fuels. The SIDI engine was tested with the E0, E30 and E85 at a engine operation of 1500 rpm/1.5 BMEP. The combustion pressure and mass burn fraction (MBF) according to the control parameters and ethanol fractions were analyzed. To verify the PN oxidation characteristics of the ethanol blended fuels, the size-resolved PN emissions over the three-way catalyst (TWC) were determined with a DMS500. The peak pressure in the cylinder was similar regardless of the type of fuel and the particle emissions were reduced by 92 % compared to gasoline at the engine out position in the E85 fuel. The results show that gasoline-ethanol blends have potential as alternative fuels and are effective in reducing the particle emissions in internal combustion engines.

Switching from fossil fuels to alternative fuels requires adjusting several engine parameters to avoid a decrease in engine torque and power. This happens because of the different properties of different fuels. One of the parameters that must be set is the compression ratio. This study aims to determine the effect of increasing the compression ratio on the torque and power of the Honda CB 150R engine using 85% bioethanol (E85) as fuel. The research method used an experimental method with 2 types of fuel and variations in the compression ratio. From the research results, it can be seen that the torque and power using E85 fuel have increased respectively by 1.08% and 1.5% when compared to the standard compression ratio using fossil fuels. Pergantian bahan bakar dari fosil ke bahan bakar alternatif membutuhkan pengaturan pada beberapa parameter engine untuk menghindari terjadinya penurunan pada torsi dan daya mesin. Hal ini terjadi karena perbedaan dari properties bahan bakar yang berbeda. Salah satu parameter yang harus di atur adalah rasio kompresi. Penelitian ini bertujuan untuk mengatahui pengaruh dari peningkatan rasio kompresi terhadap torsi dan daya engine Honda CB 150R menggunakan bahan bakar bioetanol 85% (E85). Metode penelitian menggunakan metode eksperimen dengan 2 jenis bahan bakar dan variasi pada rasio kompresi. Dari hasil penelitian terlihat bahwa torsi dan daya dengan menggunakan bahan bakar E85 mengalami peningkatan masing-masing sebesar 1,08 % dan 1,5 % jika dibandingkan dengan rasio kompresi standard menggunakan bahan bakar fosil.

For the time being biofuel is an important alternative to reduce the pollution caused by conventional based petroleum. One of the most common biofuels is the mix of bioethanol and gasoline in different percent. USA and EU use E22 and E85 (the number is the ethanol percent) as a fuel for diverse cars models. The main aim of this research was characterized the electrochemical behaviour of a gasoline level sensor that is made of metallic inks immerse in E85 fuel as an electrolyte, the sensor was divided in different zones. The electrochemical techniques employed were potentiodynamic polarization (PP) and electrochemical impedance spectroscopy (EIS). Analysis by PP and EIS showed that in zone 1A (resistive ink) present a higher corrosion resistance, while when all zones and a connector are immersed in E85 the corrosion resistance decreases.

Highlights • Coronavirus COVID-19 is spreading very fast in Brazil. • Fast deployment of alcohol-based disinfectants is needed. • Disinfectant from common ethanol of gas stations in Brazil., Objectives Coronavirus COVID-19 is spreading very fast in Brazil, requiring innovative strategies for the fast deployment of disinfectants. Panic in population triggered by COVID-19 has caused a shortage of alcohol-based hand sanitizers and disinfectants in many cities of Brazil. Despite the governmental reaction against the outbreak, a risk of shortage of disinfectants still exists. The objective of this research is to investigate an alternative method for the fast deployment of alcohol-based disinfectants to protect the population against COVID-19. Methods and results This research highlights the feasibility of disinfectant production from common ethanol available in Brazilian gas stations, as a last resort. A four-by-one (4:1) ratio of common alcohol diluted in water meets the minimum requirements set by health agencies for the alcoholic concentration of disinfectants. Risks factors on alcohol dilution process are associated with corresponding measures of risk mitigation for public health and safety. Conclusions and perspectives This research proposes a process for the production and deployment of ethanol-based disinfectant from gas stations. However, the implementation is not timely possible for the COVID-19 pandemic due to complexities in the productive process. For the post-COVID-19 period, the authors give three perspectives: (a) future investigation of human dermal toxicity of common ethanol, (b) establishment of a program for the ethanol decontamination, and (c) countries such as the US, Sweden, Thailand, and Colombia to rethink their energy policy for the adoption of biofuel E100 (ethanol and water) instead of E85 (blend of ethanol, gasoline, and water), as part of their biodefense strategy.

Biofuels have often been considered to have an advantage towards global warming but have caused controversy over competition for the limited availability of natural resources and the adverse impacts on other environmental aspects. This study evaluates the environmental benefits and impacts of biofuels in Thailand by using life cycle assessment with the Thai Eco Scarcity method derived from existing policies in Thailand. The assessment results showed that E85 (85% ethanol from cassava blended with 15% gasoline) and palm biodiesel had 95% and 43% higher impacts than their fossil fuel counterparts. The evaluation of biodiesel and ethanol revealed many trade-offs between environmental impacts; for example between fossil energy resources and other natural resources i.e. freshwater and land, and also between global (greenhouse gas emissions) and local impacts (pesticides). The importance of using the life cycle thinking concept which avoids problem shifting between impacts and between life cycle stages was also revealed. This is a crucial message in policy-making which has largely equated environmental impacts with greenhouse gas emissions leading to unintended consequences on other impacts. As anticipated, both biofuels perform much better than their fossil counterparts when considering greenhouse gas emissions and fossil energy resources. However, including other impact categories, particularly land and freshwater resources, pesticides use and mineral resources completely reverses the comparison, with the fossil counterparts ending up with better environmental profiles. Using a policy-based life cycle impact assessment method reveals comparative results and trade-offs on a single scale which can be easily understood by the policy-makers.

Lean operation of Spark-Ignition engines can provide higher thermal efficiency compared to standard stoichiometric operation. However, for a homogeneous lean mixture, the associated reduction of flame speeds becomes an important issue from the perspective of robust ignition and fast flame spread throughout the charge. This study is focused on the use of a lean partial fuel stratification strategy that can stabilize the deflagration, while sufficiently fast combustion is ensured via the use of end-gas autoignition. The engine has a spray-guided Direct-Injection Spark-Ignition combustion system and was fueled with either a high-octane certification gasoline or E85. Partial fuel stratification was achieved using several fuel injections during the intake stroke in combination with a small pilot-injection concurrent with the Spark-Ignition. The results reveal that partial fuel stratification enables very stable combustion, offering higher thermal efficiency for parts of the load range in comparison to well-mixed lean and stoichiometric combustion. The heat release and flame imaging demonstrate that the combustion often has three distinct stages. The combustion of the pilot-injected fuel, ignited by the normal spark, acts as a “super igniter,” ensuring a very repeatable initiation of combustion, and flame incandescence reveals locally rich conditions. The second stage is mainly composed of blue flame propagation in a well-mixed lean mixture. The third stage is the compression autoignition of a well-mixed and typically very lean end-gas. The end-gas autoignition is critical for achieving high combustion efficiency, high thermal efficiency, and stable combustion. Partial fuel stratification enables very effective combustion-phasing control, which is critical for controlling the occurrence and intensity of end-gas autoignition. Comparing the gasoline and E85 fuels, it is noted that achieving end-gas autoignition for the higher octane E85 requires a more aggressive compression of the end-gas via the use of a more advanced combustion phasing or higher intake-air temperature.

A prototype opposed-piston engine was tested with gasoline, ethanol, methyl tert-butyl ether (MTBE) and a gasoline–ethanol blend (E85) at full load. This is the first test of an opposed-piston engi...

Gasohol spills may easily descend through the soil column down and impact sensitive receptors as contaminants dissolve into the groundwater. Gasoline formulations are commonly blended with ethanol to alleviate environmental and economic issues associated with fossil fuels. However, the amount of ethanol added to gasoline and the groundwater hydraulic regime can significantly affect BTEX plume dynamics and lifespan. In this study, two long-term (5 and 10 years) field-scale gasohol releases with ethanol contents of 85% (E85) and 24% (E24), respectively, were assessed to discern the different dynamics undergone by gasohol blends. Statistical, geochemical, microbiological and trend approaches were employed to estimate the influence of groundwater flow variations on ethanol and dissolved BTEX transport, and the associated biodegradation rates of different gasohol blend spills. Ethanol and BTEX groundwater flow were quantified in terms of breakthrough curve characteristics, plume centroid positions and spreading, source depletion and mass degradation rates. In addition, bromide migration was evaluated to address the contribution of flow-driven dissolution. Results revealed that the high amount of ethanol along with a fast and dynamic flow exerted a flushing behavior that enhanced BTEX dissolution, migration (vertical and horizontal) and concentrations in groundwater. The higher amount of ethanol in E85 enhanced BTEX dissolution (and bioavailability) relative to E24 site and led to faster biodegradation rates, which can be explained by the cosolvency effect and metabolic flux dilution. Therefore, flow field dynamics and high ethanol content in gasohol blends enhance BTEX migration and biodegradation in gasohol-contaminated sites. The balance of these factors is crucial to determine fate and transport of contaminants in field sites. These findings suggest that hydraulic regime should be spatially and temporally characterized to support decisions on appropriate monitoring plan and remedial strategies for gasohol spills.

The usage of ethanol and two different mixtures of ethanol and gasoline (E85 and E65) was investigated on a modified diesel engine designed to work in a dual-fuel combustion mode with intake manifold alcohol injection. The tests were conducted at five operating points covering low, medium and high load and different engine speeds. Additionally, an engine-process simulation model was built for the test engine and selected operating points from the engine test bed measurements were analysed with it. The discussion of the simulation results allows an efficiency analysis and therefore a better understanding of the findings of the engine test stand experiments. With rising alcohol amount, a significant reduction of soot mass and particle count was observed at all operating points. At some load conditions, substituting diesel with ethanol, E65 or E85 led to a reduction of the NOx emissions; however, the real benefit concerning the nitrogen oxides was introduced by the mitigation of the soot–NOx trade-off. The indicated engine efficiency in dual-fuel mode showed an extended tolerance against high EGR rates. It was significantly improved with enhanced substitution ratios at high loads, whereas it dropped at low loads. Substituting diesel with manifold injected alcoholic fuels impressively reduced the engine CO2 emissions at medium and high load operating points. Degrading combustion quality, irregular combustion phenomena and poor process controllability at low load and knock as well as auto-ignition at high load limited the maximum ethanol energy share to approximately 70% and 30%, respectively.

This paper investigates the effect of some biofuels on thermal balance and performance characteristics of a single-cylinder, four-stroke SI internal combustion engine. In this study, total and instantaneous energy balance of an air-cooled, small-scale engine using various biofuels is investigated. An experimental study is carried out on gasoline engine to validate the numerical calculations. Bio-alternative fuels which include methanol, ethanol and 2-ethanol–gasoline-blended fuels consisting of E85, E15 are examined numerically. Results indicate that methanol is the most effective fuel in aspect of power generation. Ethanol, E85, E15 and gasoline are placed in next positions, respectively. Break specific fuel consumption shows totally reversed trend. It is evaluated that by increasing engine speed, heat transfer to brake power ratio decreases and lower percentage of energy in form of heat transfer is lost. The least heat transfer to brake power ratio among studied fuel is related to methanol which approves it as the most efficient biofuel. Based on instantaneous in-cylinder energy balance analysis, at the end of combustion and during expansion stroke, instantaneous brake work of fuels outpaces each other at around 40° crank angle aTDC.

The study focused on the numerical investigation for predicting engine performance and emission for a diesel engine using different fuels. The study reviewed recent literature on the effect of biofuels blend for maximizing the emission reduction for a sustainable environment. The key issues with the existing fuels have been briefly discussed in this article. The study investigated performance and emission characteristics using ethanol 85% blend denoted as E85 and Decane as an alternative fuel and compared the results with petroleum diesel fuel. The important physio-chemical fuel properties have been studied and compared with that of the commercial diesel fuel. The engine specification and other relevant information have been presented. The study investigated engine performance numerically by software tool by varying engine speeds at 1200 rpm, 1600 rpm, 2000 rpm and 2400 rpm at full load condition. The result presents the engine performance (such as BP, BSFC, BTE) and emission characteristics (CO, CO2, HC, NOx) using E85 and Decane and compared them with diesel at the same operating conditions. The study found that E85 fuel significantly reduces emission compared to Decane and diesel, however, it shows a poor performance. The numerical results were validated by experimental results and the reliability of the finding was discussed with an error analysis. Finally, the study recommended for more study on those fuels running at varying different engine operating conditions and using fuel blends.

We examine the pass-through of wholesale prices to retail prices in the market for E85, which contains 51%–83% ethanol, and in the much larger market for E10, which contains 10% ethanol. We use a panel dataset consisting of monthly observations from 2007 to March 2015 on wholesale and retail prices for 274 Minnesota gas stations that sell both E10 and E85. Consistent with prior research, the cumulative pass-through coefficient for E10 is 1.00 after one month. In contrast, the E85 market is sparse, and although pass-through increased over time, we estimate it to be only 0.53 statewide from 2012 to 2015. Pass-through is higher at stations with more local E85 competitors. In the Twin Cities, which has a high density of E85 stations, pass-through is nearly complete, but outside the Twin Cities slightly less than half the wholesale discount of E85, relative to E10, is passed on to the consumer.

In internal combustion engines, a significant share of the fuel energy is wasted via the heat losses. This study aims to understand the heat losses and analyze the potential of the waste heat recovery when biofuels are used in SI engines. A numerical model is developed for a single-cylinder, four-stroke and air-cooled SI engine to carry out the waste heat recovery analysis. To verify the numerical solution, experiments are first conducted for the gasoline engine. Biofuels including pure ethanol (E100), E15 (15% ethanol) and E85 (85% ethanol) are then studied using the validated numerical model. Furthermore, the exhaust power to heat loss ratio (Q˙ex/Q˙ht) is investigated for different compression ratios, ethanol fuel content and engine speed to understand the exhaust losses potential in terms of the heat recovery. The results indicate that heat loss to brake power ratio (Q˙ht/W˙b) increases by the increment in the compression ratio. In addition, increasing the compression ratio leads to decreasing the Q˙ex/Q˙ht ratio for all studied fuels. According to the results, there is a direct relationship between the ethanol in fuel content and Q˙ex/Q˙ht ratio. As the percentage of ethanol in fuel increases, the Q˙ex/Q˙ht ratio rises. Thus, the more the ethanol in the fuel and the less the compression ratio, the more the potential for the waste heat recovery of the IC engine. Considering both power and waste heat recovery, the most efficient fuel is E100 due to the highest brake thermal efficiency and Q˙ex/Q˙ht ratio and E85, E15 and E00 (pure gasoline) come next in the consecutive orders. At the engine speeds and compression ratios examined in this study (3000 to 5000 rpm and a CR of 8 to 11), the maximum efficiency is about 35% at 5000 rpm and the compression ratio of 11 for E100. The minimum percentage of heat loss is 21.62 happening at 5000 rpm and the compression ratio of 8 by E100. The minimum percentage of exhaust loss is 35.8% happening at 3000 rpm and the compression ratio of 11 for E00. The most Q˙ex/Q˙ht is 2.13 which is related to E100 at the minimum compression ratio of 8.

Due to the increased use of environmentally friendly fuels, it becomes imperative to evaluate the impact of biofuels on the performance of materials used in auto parts. The corrosive effects of biofuels are important in terms of durability of auto-parts since there is an evidence of the increasing deterioration in automobile parts with the long-term use of biofuels. In this research, the behavior of metals, used in the manufacturing of auto parts, in pure bioethanol (E100) and bioethanol-gasoline blends with 30% (E30), 50% (E50), and 85% (E85) of ethanol content were evaluated. Electrochemical impedance Spectroscopy (EIS) curves were done under static conditions at 45 °C. The metallic materials evaluated were stainless steel, tin, carbon steel and copper. The EIS diagrams showed two capacitive arcs for all materials. The high frequency arc was related to the dielectric response of the fuel blends, while the second one shows the characteristics and activity of the metal/fuel interface. According to the transfer resistance (Rt) obtained from the second arc of the EIS measurements, copper and carbon steel exhibited corrosion susceptibility in all fuel blends, while stainless steel and tin showed good anticorrosion behavior by showing high Rt values. The highest charge transfer resistance was showed by tin, followed by stainless steel, carbon steel and copper. Except for carbon steel and copper, the other set samples were compatible with the evaluated blends., Corrosion; Electrochemical techniques; Bioethanol; Metals.

In this thesis the effects of two future greenhouse gas emissionreducing strategies in the passenger transport sector are investigated.Three factors were modelled for 2021-2055; The life cycle emissions offour vehicle types using a well-to-wheel life cycle analysis tool calledGREET, the growth curve of these vehicle types was analyzed andextrapolated to obtain total vehicle predictions and the mileage ofthese vehicles was extrapolated from existing governmental data. Theresulting scenarios show that in the short term E85 ex fuel vehicles arecapable of more avoided emissions, with EVs outperforming them inthe long term. However limitations in the prediction of vehicle mileageleaves the overtake point to be determined.

In view of the new emission regulations seeking to lower the particle cut-off size down to the current 23 nm, an extensive comprehension on the nature of sub-23 nm particles is crucial. In this regard, a new challenge lies ahead considering an even more massive use of biofuels. The objective of this research study was to characterize the sub-23 nm particles and to evaluate their volatile organic fraction (VOF) from a high performance, 1.8 L gasoline direct injection (GDI) engine under the Worldwide harmonized Light vehicles Test Cycle (WLTC). Particle emissions were measured through an Engine Exhaust Particle Sizer (EEPS) capable of particle sizing and counting in the range 5.6 - 560 nm. The sampling and conditioning were performed by both a single diluter and the Dekati Engine Exhaust Diluter (DEED) a Particle Measurement Programme (PMP) compliant sample conditioning system. The temperature of the dilution air at the first dilution stage and of the evaporation chamber in the DEED were varied to promote nucleation and condensation phenomena thus allowing to distinguish the VOF. The effect of ethanol at 10 %v/v (E10) and 85 %v/v (E85) blend on particle emissions was analyzed. The weight of sub-23 particles on the total emissions was assessed at each phase of the cycle. Main results highlighted that sub-23 nm particles give an important contribution to the total particle emissions. A strong reduction of particle concentration as the ethanol content in the fuel increases was observed. Moreover, the test performed at low dilution temperature showed a large number of su-23 nm particles thus revealing a large fraction of volatile components in specific phases of the cycle.

Experimental work and analysis was done to investigate engine startup robustness and emissions of a flex-fuel spark ignition (SI) direct injection (DI) engine. The vaporization and other characteristics of ethanol fuel blends present a challenge at engine startup. Strategies to reduce the enrichment requirements for the first engine startup cycle and emissions for the second and third fired cycle at 25°C ± 1°C engine and intake air temperature were investigated. Research work was conducted on a single cylinder SIDI engine with gasoline and E85 fuels, to study the effect on first fired cycle of engine startup. Piston configurations that included a compression ratio change (11 vs 15.5) and piston geometry change (flattop vs bowl) were tested, along with changes in intake cam timing (95,110,125) and fuel pressure (0.4 MPa vs 3 MPa). The goal was to replicate the engine speed, manifold pressure, fuel pressure and testing temperature from an engine startup trace for investigating the first fired cycle for the engine. Results showed bowl piston was able to enable lower equivalence ratio engine starts with gasoline fuel, while also showing lower IMEP at the same equivalence ratio compared to flat top piston. With E85, bowl piston showed reduced IMEP as compression ratio increased at the same equivalence ratio. A preference for constant intake valve timing across fuels seemed to indicate that flattop piston might be a good flex-fuel piston. Significant improvements were seen with higher CR bowl piston with high fuel pressure starts, but showed no improvement with low fuel pressures. Simulation work was conducted to analyze initial three cycles of engine startup in GT-POWER for the same set of hardware used in the experimentations. A steady state validated model was modified for startup conditions. The results of which allowed an understanding of the relative residual levels and IMEP at the test points in the cam phasing space. This allowed selecting additional test points that enable use of higher residual levels, eliminating those with smaller trapped mass incapable of producing required IMEP for proper engine turnover. The second phase of experimental testing results for 2nd and 3rd startup cycle revealed both E10 and E85 prefer the same SOI of 240°bTDC at second and third startup cycle for the flat top piston and high injection pressures. E85 fuel optimal cam timing for startup showed that it tolerates more residuals compared to E10 fuel. Higher internal residuals drives down the O requirement for both fuels up to their combustion stability limit, this is thought to be direct benefit to vaporization due to increased cycle start temperature. Benefits are shown for an advance IMOP and retarded EMOP strategy at engine startup. Overall the amount of residuals preferred by an engine for E10 fuel at startup is thought to be constant across engine speed, thus could enable easier selection of optimized cam positions across the startup speeds.

The effects of ethanol/gasoline blended fuel composed of gasoline with ethanol as additives in volume basis, on spray characteristics were experimentally investigated. Tests were carried out under various ambient pressure and fuel temperature. The results show that the spray would convert to superheated states by reducing the ambient pressure or increasing the fuel temperature. The influence of ambient pressure and fuel temperature on the macroscopic spray patterns become more significant with higher ethanol fraction fuels. At the end of the injection, the E85 spray penetration under the cold-jet condition is about 11% shorter than that with gasoline, and the E85 spray penetration under flash-boiling condition is about 20% longer than that with gasoline. The spray penetration rate increases and the total penetration extends obviously with higher injection pressure. Under the flash-boiling conditions, the spatial structure close to the injector tip presents a hollow cone structure, but the spatial structure far from the tip is obviously different for various fuels due to the different degree of flash-boiling collapse.

A bstract-Biofuel contamination by water becomes a very important issue, as biofuel usage is getting more popular. Therefore, real-time monitoring of water content in biofuel is very critical. This paper presents a split ring resonator-based sensor for measurement of the volumetric percentage of biofuel components. Since biofuel of interest, E85, consists of three components, ethanol, gasoline, and water, more measurement features are introduced in this work by employing frequency shifts of higher harmonics of a split ring resonator as well as the fundamental resonance. The overall precision in the volumetric measurement of all the components of completely dissolved mixtures is achieved with the total mean-square error of less than 0.85%.

This paper investigated the effect of different substitution ratios of neat ethanol (E100) and ethanol–gasoline blend E85 on in-cylinder combustion, engine efficiency, and exhaust emissions, in a dual-fuel diesel engine, using the ethanol–diesel blend (DE95). Experimental studies realized at 1400 rpm, 1600 rpm, and 1800 rpm engine speeds under constant engine load of 50% (20 Nm). For each engine speed, the injection timing of diesel and E95 fuels at 24 °CA bTDC kept constant while low-reactivity fuels (i.e., E100 and E85) substitution ratio changed in the range of 59–83%. The results showed that premixed fuels in different SRs have an impact on shaping engine emissions, ignition delay (ID), in-cylinder pressure, and heat-release rate. Also, at the dual-fuel experimental studies in all engine speeds, NOx about 47–67% decrease compared to single fuel conditions of reference diesel and DE95, and smoke opacity remained unchanged around 0.1 FSN, whereas HC and CO increased in the range of 20–50%. However, E85/DE95 and E100/DE95 dual-fuel combustion achieved lower brake thermal efficiency (BTE) and combustion efficiency compared to single diesel fuel combustion. On the other hand, in dual-fuel combustion conditions, despite the low combustion efficiency, premixed E85 fuel offered higher engine efficiency and lower exhaust emissions than E100.

This paper focusses on the application of bioalcohols (ethanol and butanol) derived from seaweed in Heavy-Duty (HD) Compression Ignition (CI) combustion engines. Seaweed-based fuels do not claim land and are not in competition with the food chain. Currently, the application of high octane bioalcohols is limited to Spark Ignition (SI) engines. The Reactivity Controlled Compression Ignition (RCCI) combustion concept allows the use of these low carbon fuels in CI engines which have higher efficiencies associated with them than SI engines. This contributes to the reduction of tailpipe CO2 emissions as required by (future) legislation and reducing fuel consumption, i.e. Total-Cost-of-Ownership (TCO). Furthermore, it opens the HD transport market for these low carbon bioalcohol fuels from a novel sustainable biomass source. In this paper, both the production of seaweed-based fuels and the application of these fuels in CI engines is discussed. Ethanol and butanol are considered as the most viable fuels derived from seaweed. The potential of these fuels has been evaluated for the dual-fuel RCCI mode regarding efficiency and NOx emissions. The operating conditions that have been varied are mainly the fuel blend ratio (BR), fuel injection timing, and EGR rate on both a HD single-cylinder and on a HD multi-cylinder engine. The results for E85/diesel-RCCI demonstrate that CI engine-like efficiencies are feasible. The gross Indicated Thermal Efficiency (ITE) reaches up to 52% and 46.5% using E85 in a single-cylinder and a multi-cylinder engine, respectively. The first results using biomass based butanol show greater difficulty in realizing targeted efficiencies on the multi-cylinder engine due to the higher fuel reactivity and higher boiling temperature than ethanol. The gross ITE reaches up to 51.6% and 38.5% using butanol in a single-cylinder and a multi-cylinder engine, respectively. The demonstrated potential of seaweed-based fuels is an important driver for upscaling the production process of these fuels. Furthermore, future development activities will focus on improving the brake thermal efficiency of the RCCI engine running on seaweed-based fuels. Improving the low reactivity fuel-air mixture preparation will be key to achieve this.

After the implementation of a biofuel target in 2017, China, the second largest consumer of oil in the world, accelerated the development of lignocellulosic biomass technology to produce ethanol and minimized food security risks commonly associated with first generation biofuel production. In this study, Life Cycle Assessment (LCA) is used to investigate three new lignocellulosic biomass refinery systems based on corncob which co-produce ethanol with chemicals and energy. The bioethanol is used in E10 and E85 biofuel mixes and these are compared with a fossil gasoline reference system. Using 1 km distance driven by a compact size flexible fuel passenger vehicle as the functional unit and a exergy allocation approach to the raw material inputs and to the co-products in the simulated multifunctional biorefinery processes, the results indicate that regardless of the configuration of the ethanol-biorefinery, ethanol-blended fuels performed better than gasoline in terms of fossil fuels depletion (E10 6% lower; E85 64-70% lower), global warming potential (E10 1-10% lower; E85 5-113% lower) and human toxicity potential (E10 6-7% lower; E85 72-75% lower), but worst in terms of ozone layer depletion (E10 4.5-6.8 times higher; E85 51.9-78.2 times higher), acidification (E10 30-50% higher; E85 3.3-5.5 times higher) and eutrophication potential (E10 5.2-7.0 times higher; E85 42.4-64.0 times higher) than gasoline. Refereed/Peer-reviewed

To study the possibility of operating a traditional diesel engine as a partially premixed compression ignition engine, E85 created from 85% bioethanol and 15% unleaded Iraqi gasoline blend was used as the main fuel. E85 blend fuel has a low evaporation temperature, large latent heat and low cetane number (CN). Iraqi diesel fuel was used as a pilot fuel to assure ignition. High rate of cooled exhaust gas recirculation was used. The engine performance and emissions, particularly NOx–smoke trade-off, was also investigated. In order to reduce the number of experiments to be performed, the tests were conducted at a speed of 1500 rpm, with changes in the recirculated exhaust gas rate (10%, 30% and 50%) and change in injection timing (20°, 22°, 25°, 28° and 32° BTDC). Practical results showed that a significant improvement could be achieved in the NOx–PM trade-off. The ignition delay period can be increased by using a low-CN fuel accompanied with a low oxygen intake charge. When using the PPCI system, low levels of NOx and PM can be achieved without affecting the brake thermal efficiency of the engine. Smoke can be reduced even when the EGR percentage is increased under a mixed condition. ED10 (90% E85 + 10% diesel) had the largest decline in NOx (84.66%) and smoke (55.8%) compared to diesel.

A ″cradle-to-wheel" life cycle analysis was carried out to investigate the environmental profile of bioethanol (EtOH) production from lignocellulosic wheat straw (WS) and its use as transport fuel in E10 (10% of EtOH and 90% of gasoline) and E85 (85% of EtOH and 15% of gasoline) vehicles. The aims of this study were: (i) to evaluate the environmental performance of the whole WS-EtOH supply chain and (ii) to identify the best performing feedstock for a prospective bio-refinery network in Campania Region (Southern Italy). A comparison of WS-EtOH system against the fossil counterpart (gasoline passenger car) and similar bio-based production-use chains was conducted to fulfil one of the main goals of EnerBiochem and BioPoliS projects: investigating the environmental profitability of a bio-refinery system in Campania Region. Starting from the use of residual feedstock (wheat straw) or the revaluation of marginal lands (cultivation of dedicated perennial giant reed or annul fiber sorghum), through the investigation of an advanced lignocellulosic conversion processes, this work assesses the environmental feasibility of bio-energy production in Campania Region. The WS-E10 environmental profile was driven by the gasoline input in the blend, whilst the WS-E85 results showed the relevance of the crop phase. The comparison of the different blends and the gasoline-fuelled car highlighted for E10-blends similar profiles for almost all the impact categories, nearly overlapping with the conventional vehicle. Differently, for E85 vehicles, the differences between the bio-based systems appeared amplified according to the specific impacts of the feedstock supply and the conversion steps. On the whole, Fiber Sorghum-E85 system showed the worst environmental profile whilst WS-E85 entailed the best performance.

[EN] This work compares the performance and emissions of two dual-mode combustion concepts over different driving cycles by means of vehicle systems simulations. The dual-mode concept relies on switching between the dual-fuel concept known as reactivity controlled compression ignition (RCCI) and conventional diesel combustion (CDC) to cover the whole engine map. The experimental RCCI maps obtained with diesel-E85 and diesel-gasoline used as inputs to perform the simulations were obtained in a high compression ratio light-duty diesel engine (17.1:1) following the same mapping procedure in both cases. The driving cycles simulated to perform the comparison were the Real Driving Emissions cycle (Europe), Worldwide harmonized Light vehicles Test Cycle (Europe), Federal Test Procedure FTP-75 (United States) and JC08 (Japan). The results show that the dual-mode concept has potential to be implemented in flexible-fuel vehicles. Using gasoline as low reactivity fuel (LRF) for RCCI, the vehicle mileage would be equal to CDC, but having reductions in NOx and soot emissions of 16% and 50%, respectively, along the RDE cycle. Using E85 instead of gasoline, the reductions in NOx and soot emissions increase up to 50% and 85%, respectively, but in this case promoting higher thermal efficiency than CDC. (C) 2018 Elsevier Ltd. All rights reserved., The authors gratefully acknowledge General Motors Global Research & Development for providing the engine used to acquire the experimental data shown in this investigation. The authors also acknowledge FEDER and Spanish Ministerio de Economia y Competitividad for partially supporting this research through HiReCo project (TRA2014-58870-R).

Gasoline Direct Injection (GDI) engines are increasingly available in the market. Such engines are known to emit more Particulate Matter (PM) than their port-fuel injected predecessors. There is also a widespread use of oxygenate fuels in the market, up to blends of E85, and their impact on PN emissions is widely studied. However the impact of oxygenate fuels on PN emissions from downsized, and hence highly-boosted engines is not known. In this work, PN emissions from a highly boosted engine capable of running at up to 35 bar Brake Mean Effective Pressure (BMEP) have been measured from a baseline gasoline and three different oxygenate fuels (E20, E85, and GEM – a blend of gasoline, ethanol, and methanol) using a DMS500. The engine has been run at four different operating points, and a number of engine parameters relevant to highly-boosted engines (such as EGR, exhaust back pressure, and lambda) have been tested – the PN emissions and size distributions have been measured from all of these. The results show that the oxygenate content of the fuel has a very large impact on its PN emissions, with E85 giving low levels of PN emissions across the operating range, and GEM giving very low and extremely high levels of PN emissions depending on operating point. These results have been analysed and related back to key fuel properties.

The paper presents the results of the investigation of Dual Fuel (DF) diesel engines powered by high bioethanol contain fuel – E85. The object of the investigation is a three-cylinder Compression Ignition (CI) Internal Combustion Engine (ICE) powered by diesel oil and bioethanol fuel E85 injected into the intake port as a DF engine. With the increase in the share of E85 fuel the highest intensification of the combustion process takes place in the main stage of the combustion and the ignition delay increases as well. The researchers are conducted using Computational Fluid Dynamics (CFD) method; the results of the investigation are successfully verified based on the indicator diagrams, heat performance rate and emissions. Based on CFD results the cross sections investigation of the combustion chamber it can be seen that in case of the DF engine, the flame front propagates with a higher speed. The initial phase of the combustion starts in a different location of the combustion chamber than in the classic CI engine. Replacement of diesel fuel by E85 in 20% resulted in the shortening of the combustion duration more than 2-times. With the increase of energetic share in E85 the soot emission is decreased at all ranges of the analysed operations of the engine. The oppositerelationship was observed in case of NO emission. With the increase of E85 in the fuel, the emission of NO increased.

Compliance with the Renewable Fuel Standard (RFS) in the United States will require price incentives for a substantial number of motorists with flex‐fuel vehicles to switch to high ethanol‐gasoline blends. Existing estimates of motorists’ willingness to pay for high‐ethanol blends use data from Brazil, data generated when prices greatly favored low‐ethanol blends, or stated preference data collected from mail and online surveys. We conducted an intercept survey of flex motorists as they refueled in five U.S. states. We overcome the problem caused by sample prices favoring low‐ethanol blends by augmenting revealed preference data with stated preference data. A sample‐selection problem arises because motorists with high willingness to pay seek out the relatively few stations that sell high‐ethanol blends. We use responses from two questions to inform sample selection. We find the average U.S. motorist requires a substantial discount to switch to high ethanol blends beyond the price that equates the cost per mile of driving.

Testing of real driving emissions (RDE) with portable emission measuring system (PEMS) in an appropriate road circuit became an obligatory element of new type approval of passenger cars since September 2017. In several projects the Laboratory for Exhaust Emissions Control (AFHB) of the Berne University of Applied Sciences (BFH) performed comparisons on passenger cars with different PEMS’s on chassis dynamometer and on road, considering the quality and the correlations of results. Particle number measuring systems (PN PEMS) were also included in the tests. The present paper informs about influences of E85 on RDE on two flex-fuel-vehicles, discusses some aspects of different ways of evaluation with different programs, shows comparison of different types of PN PEMS and represents the effects of simulation of slope on the chassis dynamometer.

Exergy is a quantity of the work potential of energy from a given thermodynamic condition. Unlike energy, exergy can be destroyed, and for gasoline engines, the major source of this destruction is during the combustion process. Therefore, to assess the quality of gasoline engines, the research team examined the effect of inlet temperature and spark timing on chemical, thermo-mechanical and total exergy of fuel using E0, E20, E40, E60 and E85 fuels. Results showed that by advancing the spark timing (20° bTDC), thermo-mechanical exergy has increased but chemical exergy and total exergy have decreased. In addition, advance or delay in spark timing had no effect on the fuel chemical exergy for the compression and expansion strokes. The effect of temperature on exergy parameters indicated that by reducing inlet temperature (320 K), exergy parameters increased. In other words, the fuel chemical exergy at 320 K for E0, E20, E40, E60 and E85 fuels, increased by 7%, 7.1%, 7.2%, 7.2%, 7.3%, respectively, than 350 K and increased by 14%, 14.3%, 14.4%, 14.4% and 14.5% than 380 K.

A cradle-to-wheel life cycle analysis evaluated the greenhouse gas (GHG) contribution and fossil energy consumption (FEC) of bio-ethanol (EtOH) from dedicated crops on marginal lands in Campania Region (Southern Italy). The analysis processed experimental agronomic data of giant reed cultivated on hilly areas at high erosion risk and industrial data of feedstock conversion to EtOH, through second generation innovative technologies. Two ethanol–gasoline mixes (E10 and E85) were considered and compared with gasoline vehicle (GV). The E10 GHG and FEC profiles were driven by the gasoline input in the blend and the linked CO2 tailpipe emissions. The EtOH supply chain, especially the crop phase, was the major contributor to E85 impacts. The higher amount of biogenic C in E85 determined a marked reduction over GV of both GHG emissions (−60%) and FEC (−65%). The soil carbon storage would save 25 g CO2 eq per MJ; however, the issue is controversial due to the spatial and temporal variability of the process. Based on land availability, E85 contribution to renewables in the regional transport sector would amount to 4% and the blend wall would be far from saturation. A possible mismatch between future flexi-fuel vehicles density and E85 availability should be considered. © 2018 Elsevier Ltd

The study investigated the combustion and emissions of gasoline engines using four ethanol–gasoline blends ranging from 10 to 85 volume percent ethanol, and an E0 control Performance were compared in single cylinder engine and tested in a chassis dynamometer using two Tier I vehicles. The octane sensitivity of the fuels increases with the addition of ethanol from 7.8 for a non-oxygenated fuel to 23 for the 85% ethanol blend. Fuel sensitivity have a direct relationship with the latent heat of vaporization, because charge cooling is one of the way alcohols increases Research Octane Number. For the primary gaseous compounds, an increase in total hydrocarbon emissions and a decrease in aromatic BTEX compounds was detected as the amount of ethanol in the fuel increased. Both vehicles operated without engine fault code display except when the E-85 was used. The engine could be started stably with E10, E20, and E45. However, for E85 the engine idling became unstable because the air–fuel mixture was too lean making impossible the reduction reactions necessary for NOx emission control in the catalytic converter.

Flex Fuel Vehicles (FFVs) typically operate on gasoline or E85, an 85%/15% volume blend of ethanol and gasoline, E85. Differences in FFV fuel use and tailpipe emission rates are quantified for E85 versus gasoline based on real-world measurements of five FFVs with a portable emissions measurement system (PEMS), supplemented chassis dynamometer data and estimates from the MOtor Vehicle Emission Simulator (MOVES) model. Because of inter-vehicle variability, an individual FFV may have higher nitrogen oxides (NOx) or carbon monoxide (CO) emission rates on E85 versus gasoline, even though average rates are lower. Based on PEMS data, the comparison of tailpipe emission rates for E85 versus gasoline is sensitive to vehicle specific power (VSP). For example, although CO emission rates are lower for all VSP modes, they are proportionally lowest at higher VSP. Driving cycles with high power demand are more advantageous with respect to CO emissions, but less advantageous for NOx, compared. Chassis dynamometer data are available for 121 FFVs at 50,000 useful life miles. Based on the dynamometer data, the average difference in tailpipe emissions for E85 versus gasoline is −23% for NOx, −30% for CO, and no significant difference for hydrocarbons (HC). To account for both the fuel cycle and tailpipe emissions from the vehicle, a life cycle inventory was conducted. Although tailpipe NOx emissions are lower for E85 versus gasoline for FFVs and thus benefit areas where the vehicles operate, the life cycle NOx emissions are higher because the NOx emissions generated during fuel production are higher. The fuel production emissions take place typically in rural areas. Although there are not significant differences in the total hydrocarbon emissions, there are differences in HC speciation. The net effect of lower tailpipe NOx emissions and differences in HC speciation on ozone formation should be further evaluated. Implications Reported comparisons of Flex Fuel Vehicle (FFV) tailpipe emission rates for E85- versus gasoline have been inconsistent. To date, this is the most comprehensive evaluation of available and new data. The large range of inter-vehicle variability illustrates why prior studies based on small sample sizes led to apparently contradictory findings. E85 leads to significant reductions in tailpipe nitrogen oxides (NOx) and carbon monoxide (CO) emission rates compared to gasoline, indicating a potential benefit for ozone air quality management in NOx limited areas. The comparison of FFV tailpipe emissions between E85 and gasoline is sensitive to power demand and driving cycles.

The chronic illness of transportation sector is its excessive dependence on petroleum products that necessitates immediate actions to mitigate negative externalities. Developing an environmentally benign, economically feasible, and socially acceptable fuel portfolio can generally, improve the sustainability of future transportation systems. This study aims to predict an optimal fuel portfolio based on different concerns for light-duty vehicles of Iran in the light of alternative fuels until 2025. Six potential fossil and renewable fuels including gasoline, diesel, compressed natural gas (CNG), liquid petroleum gas (LPG), a mixture of 85% ethanol and 15% gasoline (E85) and biodiesel, and one gasoline-electric hybrid technology competed through an integrated fuzzy multi-objective programming. Seven goals with environmental, cost, social and policy nature, as well as systematic constraints and fuel priority (obtained by the application of a multi-criteria decision making (MCDM) method) had to be met in the model. The solution of the model along with the sensitivity analysis of weights and aspiration levels indicated that with an acceptable possibility of achieving the goals, CNG had the greatest share in the optimal fuel portfolio followed by gasoline, LPG and diesel. Through the intended horizon, the fossil fuels’ share has declined such that 13.5% of the optimal portfolio was replaced by hybrid technology, biodiesel and E85 in 2025, and more importantly, carbon dioxide emission and fuel cost could be mitigated by 11% and 18%, respectively in the same year. Two scenarios focusing on environmental and cost goals were defined through assigning 70% and 80% of the weights to the related goals, respectively; the results revealed that the main characteristics of the optimal portfolio were stable. Likewise, the analysis of the aspiration and tolerance levels of the goals proved the stability of the model and revealed that these parameters play a sensitive role in the model and could affect the optimality and feasibility of the solutions.

Emission factors for oxygenated polycyclic aromatic hydrocarbons (OPAHs) and PAHs have been determined from two different fuel flexible light duty vehicles operated at −7 °C in the New European Driving Cycle (NEDC) and at +22 °C in the Artemis Driving Cycle (ADC). Three different gasoline/ethanol blends, commercially available in Sweden, were tested i.e., gasoline E5, with 5% v/v ethanol and ethanol fuel E85 with 85% v/v ethanol and winter time quality E70 with 70% v/v ethanol, respectively. The results showed greatly increased emissions of both OPAHs and PAHs at cold engine start conditions (−7 °C in the NEDC) compared to warm engine start (+22 °C in the ADC). For the OPAHs, higher average total emission factors were obtained when running on E85 compared to E5 at both cold 2.72 µg/km vs 1.11 µg/km and warm 0.19 µg/km vs 0.11 µg/km starting conditions with the highest emissions when using E70 at −7 °C 4.12 µg/km. The same trend was found for the PAHs at cold engine start with higher average total emission factors when using ethanol fuel 71.5 µg/km and 60.0 µg/km for E70 and E85, respectively compared to gasoline E5 (20.2 µg/km). Slightly higher average total PAH emissions were obtained when operating at +22 °C with E5 compared to with E85 1.23 µg/km vs 0.72 µg/km.

Bioethanol (bio-EtOH) is commonly used as a renewable biofuel additive for gasoline. A novel technology producing bio-EtOH from anaerobic digestion of organic waste (OW) has recently attracted attention. This work presents a deterministic mixed integer linear programming model for the optimal location of OW-based bio-EtOH biorefineries. The proposed model considers OW treatment location, bio-EtOH biorefineries, and truck transport links as a supply chain network (SCN) approach. The objective function of the developed model is to minimize the total bio-EtOH levelized cost (ELC) while satisfying the model constraints consisting of equalities (e.g., mass and energy balances for the bio-EtOH biorefinery) and inequalities (e.g., capacity of the bio-EtOH refinery, truck transport) to meet the regional demands of bio-EtOH. To validate the optimization model, a case study based on a real scenario for South Korea in 2030 was conducted for different bio-EtOH blending rates (E10, E20, E85, E100). The case study results indicate that ELC of E10 containing 10% bio-EtOH from OW products combined with gasoline is USD 3.65/gallon. As the blending rate of bio-EtOH increases, ELC increases to USD 4.36/gallon for E20, USD 8.99/gallon for E85, and USD 10.05/gallon for E100. The optimization results can help determine SCN strategies for an OW-based biofuel economy.

Compact reforming of liquid fuels like ethanol and gasoline requires simultaneous evaporation and catalytic partial oxidation. In this work, a small-scale reactive volatilization reactor was examined for compact reforming of ethanol and 85% ethanol mixed with iso-octane (E85). Results show the reactor can simultaneously vaporize and reform both fuels with high conversion (up to ~45%) and high reforming efficiency (up to ~97%), defined as the ratio of lower heating value of the syngas over that of the fuel. The demonstrated result shows that the non-premixed configuration is a viable option for compact reforming at high molar carbon to oxygen ratio while avoiding soot formation.

This study investigated the effects of various ethanol-gasoline blends on the hazardous air pollutants (HAPs) emissions from a wall-guided direct injection passenger vehicle. The fuel economy (FE) as well as regulated and unregulated gaseous emissions was evaluated on a chassis dynamometer using the federal test procedure (FTP-75) mode. Five fuels with varying ethanol contents of E0, E10, E30, E50, and E85 were prepared by blending ethanol into commercial gasoline on a volumetric basis and were analyzed each fuel specification. The engine control schemes of fuel injection quantity for various ethanol blends were adjusted to optimize the engine starting capability, vehicle drivability and emissions performance. The FE of the E85 fueled vehicle decreased by 29% relative to gasoline fuel due to the low energy content of ethanol. Blending ethanol into gasoline produced a dramatic decrease of particulate emission, because pure ethanol has no aromatic compounds and carbon content lower than that of gasoline. As a result, nano-particles were rarely emitted in the vehicle tests of fuels with more than 30% ethanol. Carbonyl compounds emissions, which originate from partial oxidization or incomplete combustion of ethanol, also rose sharply as the ethanol content increased, while volatile organic compound (VOC) emissions were reduced considerably with medium- and high-ethanol formulations due to the lower proportion of aromatic components in these fuels.

Air pollution exposure, including passenger car emissions, may cause substantial respiratory health effects and cancer death. In western countries, the majority of passenger cars are driven by gasoline fuel. Recently, new motor technologies and ethanol fuels have been introduced to the market, but potential health effects have not been thoroughly investigated. We developed and verified a coculture model composed of bronchial epithelial cells (ECs) and natural killer cells (NKs) mimicking the human airways to compare toxic effects between pure gasoline (E0) and ethanol-gasoline-blend (E85, 85% ethanol, 15% gasoline) exhaust emitted from a flexfuel gasoline car. We drove a steady state cycle, exposed ECs for 6h and added NKs. We assessed exhaust effects in ECs alone and in cocultures by RT-PCR, flow cytometry, and oxidative stress assay. We found no toxic effects after exposure to E0 or E85 compared to air controls. Comparison between E0 and E85 exposure showed a weak association for less oxidative DNA damage after E85 exposure compared to E0. Our results indicate that short-term exposure to gasoline exhaust may have no major toxic effects in ECs and NKs and that ethanol as part of fuel for gasoline cars may be favorable.