Alternative Fuels and Hybridization as Cost-Effective Pathways to Medium-Duty Greenhouse Gas Phase 3 Compliance

This study aimed to evaluate the environmental impact of using liquefied petroleum gas (LPG) in small fishing vessels by conducting a life cycle assessment (LCA) in Korea. For the first time in the country, LPG engines designed for small fishing ships were utilized in this study. In addition, this research examined the potential benefits of employing Bio LPG, a renewable LPG produced from two distinct raw materials (crude palm oil (CPO) and refined, bleached, and deodorized (RBD) palm oil), instead of conventional LPG. The LCA findings reveal that utilizing LPG fuel in small fishing vessels can reduce greenhouse gas (GHG) emissions by more than 30% over conventional gasoline and diesel fuels. During the life cycle of vessels that use LPG fuel instead of gasoline and diesel fuels, there is a reduction of 2.2 and 1.2 million tons of GHG emissions, respectively. Moreover, substituting conventional fossil fuels with Bio LPG can result in over 65% reduction in GHG emissions. For the life cycle of boats that use Bio LPG fuel in place of gasoline and diesel fuels, the reduction of GHG emissions was 4.9 million tons and 2.5 million tons for CPO and 5.2 million tons and 2.7 million tons for RBD, respectively. This study not only underscores the substantial advantages of using Bio LPG over conventional fossil fuels but also presents conventional LPG as a way to reduce GHG emissions and promote sustainable practices in the fishing industry.

LPG (Liquefied Petroleum Gas) has been widely used as an alternative fuel for gasoline and diesel vehicles in light of clean fuel and diversity of energy resources. But conventional LPG vehicles using carburetors or MPI fuel injection systems can’t satisfy the emissions regulations and CO2 targets of the future. Therefore, it is essential to develop LPG engines of spark ignition or compression ignition type such that LPG fuel is directly injected into the combustion chamber under high pressure. A compression ignition engine using LPG is the ideal engine with many advantages of fuel economy, heat efficiency and low CO2, even though it is difficult to develop due to the unique properties of LPG. This paper reports on numerical and experimental studies related to LPG fuel for a compression ignition engine. The numerical analysis is conducted to study the combustion chamber shape with CATIA and to analyze the spray and fluid behaviors with FLUENT for diesel and LPG (n-butane 100%) fuels. In one experimental study, a constant volume chamber is used to observe the spray formation for the chamber pressure 0 to 3MPa and to analyze the flame process, P-V diagram, heat release rate and emissions through the combustion of LPG fuel with the cetane additive DTBP (Di-tert-butyl peroxide) 5 to 15 wt% at 25MPa of fuel injection pressure. In engine bench tests, experiments were performed to find the optimum injection timing, lambda, COV and emissions for the LPG fuel with the cetane additive DTBP 5 to 15 wt% at 25MPa fuel injection pressure and 1500 rpm. The penetration distance of LPG (n-butane 100%) was shorter than that of diesel fuel and LPG was sensitive to the chamber pressure. The ignition delay was in inverse proportion to the ambient pressure linearly. In the engine bench tests, the optimum injection timing of the test engine to the LPG fuel with DTBP 15 wt% was about BTDC 12° CA at all loads and 1500 rpm. An increasing of DTBP blending ratio caused the promotion of flame and fast burn and this lead to reduce HC and CO emissions, on the other hand, to increase NOx and CO2 emissions.

The United States Environmental Protection Agency has identified the use of low rolling resistance (LRR) tires as an effective fuel-saving technology for heavy-duty vehicles (HDV). However, adoption of LRR tires has been less than desired because of potential performance uncertainties under real-world operating conditions. Also, previous decision-support tools developed to help stakeholders have had limited accuracy because of inherent transient speed profiles in real-world operating cycles. This study develops a tool to predict HDV fleet-wide fuel saving from LRR tires. The tool uses empirical models to estimate the fuel-saving benefits of LRR tires as a function of vehicle characteristics, operating cycles, and route characteristics. To facilitate ease-of-use by stakeholders, the empirical models have been transformed into a Microsoft Excel spreadsheet tool. The empirical models were developed with data generated by simulating real-world HDV operating cycles with Autonomie, an advanced model for automotive control-system design, and simulating vehicle energy consumption and performance. Validation analysis of the tool shows an average error of less than 6.5%. Unlike previous tools, the developed tool is applicable to both stabilized and transient speed operations. It allows users to customize it to their specific fleet and operating conditions. This is significant and it is envisaged that the tool will facilitate more investment decisions by fleet operators, as well as help regulatory agencies and policy analysts design key policy incentives.

Compressed natural gas (CNG) and liquefied petroleum gas (LPG) are included in the group of promoted transport fuel alternatives for traditional fossil fuels in Europe. Both CNG and LPG fueled vehicles are believed to have low particle number and mass emissions. Here, we studied the solid particle number (SPN) emissions >4 nm, >10 nm and >23 nm of bi-fuel vehicles applying CNG, LPG and gasoline fuels in laboratory at 23 °C and sub-zero (−7 °C) ambient temperature conditions. The SPN23 emissions in CNG or LPG operation modality at 23 °C were below the regulated SPN23 limit of diesel and gasoline direct injection vehicles 6×1011 1/km. Nevertheless, the limit was exceeded at sub-zero temperatures, when sub-23 nm particles were included, or when gasoline was used as a fuel. The key message of this study is that gas-fueled vehicles produced particles mainly <23 nm and the current methodology might not be appropriate. However, only in a few cases absolute SPN >10 nm emission levels exceeded 6×1011 1/km when >23 nm levels were below 6×1011 1/km. Setting a limit of 1×1011 1/km for >10 nm particles would also limit most of the >4 nm SPN levels below 6×1011 1/km.

The objective of this study is to investigate and compare the performance and emission characteristics of the liquefied petroleum gas (LPG)-fuelled engine generator and the conventional gasoline-fuelled engine generator. The approach involves converting a gasoline engine generator, commonly used in Malaysian night markets to generate electricity, to the LPG engine generator. A four-stroke SI single-cylinder engine is equipped with an LPG injection system with minor modifications and then tested with both LPG and gasoline fuels. A venturi mixer (carburettor) was designed and in house constructed and then installed to deliver a proper A/ F ratio to the combustion chamber. The commercial computational fluid dynamics software FLUENT was used for simulation of air flow inside the mixer. The converted engine was tested at constant speed for its brake-specific fuel consumption (BSFC), efficiency, exhaust temperature, and exhaust gas emissions. The results show that the performance and emission characteristics of the LPG-fuelled engine are well suited for use in night markets. Average BSFC and average efficiency for the LPG engine over a range of loads were quite similar to those for the gasoline engine: the average BSFC was 0.95 kg/kWh for the LPG engine and 1 kg/kWh for the gasoline engine. The use of LPG as fuel in a gasoline engine causes only a slight reduction in efficiency as a 17 per cent reduction in average efficiency was recorded over the entire load range; however, the LPG engine fared better at higher loads than the gasoline engine for which only as low as a 4 per cent reduction was recorded at high loads. Emission tests seem to verify the minimal pollution products; there are significant reductions in the emission concentration results when LPG is used. Average decreases of 32 per cent for nitrogen oxide, 10 per cent for carbon dioxide, and 40 per cent for carbon monoxide were recorded. Although higher values of hydrocarbon (HC) were recorded, a 50 per cent reduction in HC was found for loads higher than 700 W. The study verified the more favourable features of LPG compared to gasoline as it is one of the best alternative fuels to gasoline for spark-ignition engine generators to solve the air pollution problem in night markets.

As an escalating global concern for environmentally sustainable marine fuels, liquefied petroleum gas (LPG) is attracting attention as an eco-friendly and economical alternative. This study explored LPG utilization in small marine vessels, focusing on its eco-friendliness and economic feasibility. To assess its environmental implications, the AVL FIRE simulation program was used to compare CO2, CO, NO, and soot emissions from LPG engines with those from conventional gasoline and diesel engines. The LPG engine model relied on data from a pioneering type-approved experimental LPG engine designed for small South Korean marine vessels, while parameters for gasoline and diesel engines were adjusted to suit their distinctive features. Regarding long-term economic feasibility, assuming a 30-year ship lifespan, incorporating 2022 annual average prices, average annual price growth rates, and annual fuel consumption data of each fuel, results indicate that LPG engines exhibited lower CO2, CO, NO, and soot emissions than conventional engines, except that NO emissions were higher than gasoline engines. Evaluating LPG’s economic feasibility over a 30-year ship life cycle for an individual vessel revealed varying fuel cost savings, with the greatest savings observed in gasoline–other (KRW 2220.7 million) and the least in gasoline–coastal (KRW 1152.5 million). These findings offer vital insights for ship operators and policymakers seeking a balance between eco-friendliness and cost-effectiveness, as well as LPG engine technology emerging as pivotal for a sustainable future, harmonizing environmental protection and economic viability.

Biomethane CNG hybrid: A reduction by more than 80% of the greenhouse gases emissions compared to gasoline

Experimental and numerical studies on performance investigation of a diesel engine converted to run on LPG

Investigation of in-cabin volatile organic compounds (VOCs) in taxis; influence of vehicle's age, model, fuel, and refueling

This paper presents a simulation investigation of the combustion characteristics, performance, and emission of a spark ignition engine fueled with gasoline, liquified petroleum gas (LPG), compressed natural gas (CNG), and biogas.The simulation was conducted on the advanced software AVL Boost.The engine model was customed with different fuels in the simulation, but the air excess ratio () was kept the same at 1.0.The difference in fuel properties contributed to a later combustion process for LPG, CNG, and biogas-fueled engines.The peak in-cylinder pressure was 77.7; 62.9; 68.9 and 32.2bar for gasoline, LPG, CNG, and biogas.The study's results indicated that the test engine's brake power decreased by up to 22.63; 17.22; and 39.10% on average for LPG, CNG, and biogas.However, the brake-specific energy consumption (BSEC) increased by 5.50 and 8.12% when fueled by LPG and CNG; and reduced by 27.4% for the bioag-fueled engine.Nevertheless, the exhaust emissions of the test engine that is powered by gaseous fuels significantly decreased.NOx emissions decrease by 45.04; 56.75 and 66.75% on average for LPG, CNG, and biogas fuel.The average CO level of the engine when fueling with LPG, CNG, and biogas was reduced by 91.44; 90.51 and 93.01%.The HC emission of the engine that LPG and CNG powered is considerably lower than that of the original engine, in turn, 73.72% and 69.29% on average, while a reduction of 39.22% was observed for biogas-fueled engines on average.

일반적으로 황분계 부취제는 연료가스에 인한 가스중독, 발화, 폭발 등의 사고를 방지하고, 배출가스에 의해 연료 가스 누출의 즉각적으로 손쉽게 검출할 수 있도록 LPG, LNG 그리고 도시가스와 같은 연료가스에 첨가 사용하고 있다. 본 연구에서는 새로운 비황분계 부취제(K-Petro S-Free)를 사용한 LPG 혼합연료의 엔진 성능과 배출가스(CO, THC, <TEX>$CO_2$</TEX>, <TEX>$NO_x$</TEX>, <TEX>$SO_2$</TEX> ) 특성을 살펴보았다. 새로운 비황분계 부취제를 40mg/kg를 혼합한 LPG 연료(여름용, 겨울용)와 현재 사용 중인 황분계 부취제 (EM, ethyl mercaptan)를 혼합한 LPG 연료의 엔진 성능과 배출가스 특성을 실험하였다. 비황분계 부취제를 혼합한 LPG 연료의 엔진 성능은 황분계 부취제를 혼합한 LPG 연료와 비교할 때 비슷한 결과를 보여 주었다. 한편, 비황분계 부취제를 혼합한 LPG 연료의 엔진 배출가스 중 CO, THC, <TEX>$CO_2$</TEX>, <TEX>$NO_x$</TEX>은 황분계 부취제를 혼합한 LPG 연료와 비교할 때 비슷한 특성을 보였다. 그러나 2,000rpm에서 배출가스 중 <TEX>$SO_2$</TEX>은 비황분계 부취제를 혼합한 LPG 연료가 황분계 부취제를 혼합한 LPG 연료보다 83% 감소하는 우수한 결과를 보였다. In general, odorants are added to fuel gases, such as LPG, LNG and city gas, to prevent gas poisoning, ignition, explosion, or other accident caused by fuel gases, and to enable immediate and easy detection of fuel-gas leakage by emitting an offensive smell. This study describes a study on the performance and exhaust emissions (CO, THC, <TEX>$CO_2$</TEX>, <TEX>$NO_x$</TEX>, <TEX>$SO_2$</TEX>) characteristics of liquefied petroleum gas (LPG) engine using LPG fuel with new sulfur free odorant (K-Petro S-Free). New sulfur free odorant (40 mg/kg) was added to 2 type LPG fuels for summer, and winter and it was used in performance and exhaust emissions, compare to LPG fuel with sulfur containing odorant (EM, ethyl mercaptan). Engine performance using LPG with sulfur free odorant was similar to LPG with sulfur-containing odorant. Exhaust emissions (CO, THC, <TEX>$CO_2$</TEX>, <TEX>$NO_x$</TEX>) of LPG with sulfur free odorant were also similar characteristics, compare with sulfur containing odorant. Especially, <TEX>$SO_2$</TEX> emission using LPG with K-Petro S-Free odorant was more reduced 83 % than LPG with sulfur containing odorant(EM) at 2000 rpm.

Major US electric utility climate pledges have the potential to collectively reduce power sector emissions by one-third

Oil consumption and import of China increase very quickly in recent years. Because of vehicle population growing in a tremendous speed, nearly 40% of oil has already used in transportation sector in today's China. Many kinds of alternative fuel vehicles are introduced, demonstrated and used in cities to reduce the traditional gasoline and diesel not only to reduce the regulated emissions, but also to improve the oil security of China. When the Kyoto Protocol became effective in last year, Chinese government and experts began to focus on greenhouse gas (GHG) emissions of alternative vehicle fuels. In order to comprehensively evaluating energy and global warming impact lead by production and utilization of alternative vehicle fuels in China, Well-to-Wheel analysis is used in this paper to quantitatively calculate energy use and GHG emissions of recovery, production, transportation and distribution, and end-use of compressed natural gas (CNG), liquefied petroleum gas (LPG), ethanol, methanol, dimethyl ether (DME) and Fischer-Tropsch diesel (FTD). The feedstock of ethanol includes corn and wheat. The energy use and GHG emissions of alternative vehicle fuels are compared with traditional gasoline and diesel. The results show that CNG and LPG is good choice from energy saving and GHG reduction in China. NG-based and coal-based methanol, DME and F-T diesel have lower lifecycle petroleum consumption than traditional gasoline and diesel, so that they may be an answer to Chinese oil security. The lifecycle total energy use, fossil energy use and GHG emissions of NG-based synthesized fuels are lower than coal-based fuels, but obviously higher than traditional gasoline and diesel, so that utilization of them will lead to potential pressure to China GHG reduction responsibility. The GHG emissions performance of China ethanol fuel is not as good as U.S. ethanol. The main reason is abuse of agriculture chemical in corn farming, especial the nitrogenous fertilizer, which is caused great N20 emission

&lt;div class="htmlview paragraph"&gt;In present days, most of researches concerned with vehicle engines have been performed to reduce vehicle emissions and to improve engine efficiency. For the requirements, LPG (Liquefied Petroleum Gas) engine which has lots of advantages such as low emission level, cheaper fuel cost and enough infrastructures has had lots of interest as an alternative fuel engine. What is more, it has a low emission level of CO&lt;sub&gt;2&lt;/sub&gt; well-known as the factor of ‘Global Warming’, thus the use of LPG engines has been increased. Especially since MPI(Multi Point Injection) type LPLi(Liquid Phase LPG injection) system was used for the fuel supply system, disadvantages of LPG engine such as low engine performance, decreased charging efficiency and cold starting difficulty have been improved and prejudices against LPG engines have been changed a lot. In light of this, the motion to use LPLi engines instead of diesel engines has been increasing. Therefore in this research, spray visualization experiment was performed to find the optimal LPG injection conditions for a modified diesel engine. And the effect of the ambient pressure on spray characteristics of LPLi injector was investigated in a high pressure chamber which simulates the air charging condition of the base diesel engine. As a result, the ambient pressure affects both injection quantity and spray structure. And the results provide valuable information on macroscopic spray structure and design factors for modifying LPG injection system for the engine.&lt;/div&gt;

Projection of passenger cars’ fuel demand and greenhouse gas emissions in Iran by 2050