Liquefied Natural Gas Vehicles Research Articles

Co-benefits of reducing CO2 and air pollutant emissions in the urban transport sector: A case of Guangzhou

The transport sector has become an important source of urban greenhouse gas (GHG) and air pollutant emissions, with the continuous growth of transportation demand. The co-benefits of reducing GHG and air pollutant emissions in the transport sector are receiving more and more attention. Taking Guangzhou as the case study city, this study quantitatively analyzed the co-benefits of reducing CO2 and air pollutant emissions under the sustainable scenario in the transport sector by developing a quantitative analysis model based on the Long-range Energy Alternatives Planning (LEAP) framework. The co-benefits quantitative parameter and the co-benefits radar chart analysis method are used to identify and evaluate the generated co-benefits, and then the co-benefits generated by implementing the sustainable measures are discussed. The results show that adjusting transport modes and increasing the application of electricity are the two most effective measures for achieving the co-benefits of reducing CO2 and air pollutant emissions in the Guangzhou transport sector. Thus, these two measures are highly preferential for mitigating CO2 and air pollutant emissions. In addition, increasing the application of biofuel and hydrogen energy also has good co-benefits. However, increasing the application of Liquefied Natural Gas (LNG) has poor co-benefits. Promoting the utilization of LNG intercity buses, trucks, and cargo ships will lead to emission increases of CO and HC compared to the current policy scenario, and small emission reductions of CO2 and other air pollutants. Therefore, to promote the utilization of LNG vehicles and ships, it is necessary to cooperate with the use of air pollutant end removal devices and high-pressure direct injection (HPDI) gas engines.

Life cycle assessment and Monte Carlo simulation to evaluate the environmental impact of promoting LNG vehicles

•As a novel and alternative type of fuel for heavy-duty trucks, it is very important to assess a broad array of environmental impacts of liquefied natural gas (LNG). However, few studies have evaluated comprehensively the environmental impact of LNG as an alternative fuel on human health, ecosystems and resources from a life cycle perspective. In particular, the environmental benefit of promoting LNG vehicles is often complicated and uncertain due to many variable factors, which are also often not given enough attention. This method article describes the use of a combination of life cycle assessment (LCA) and Monte Carlo simulation to evaluate the potential environmental benefits of promoting LNG heavy-duty diesel vehicles in Saguenay, a city in Canada. It not only conducts a full-range analysis of environmental impacts, but also considers the impact of joint changes in uncertain factors such as methane emission rates, energy efficiency of engine and the project promotion prospects on the environmental benefits of LNG, making life cycle environmental impact assessment more systematic and comprehensive. The paper provides the details of all the steps used in the method and can be replicated and applied to other similar studies and research settings.•This combined approach provides a comprehensive assessment of the environmental impacts incurred by the promotion of LNG vehicles. Besides, it also provides a certain degree of risk assessment for LNG projects.•This method takes into account the complexity of the joint change of multiple uncertainties, which makes up for the deficiencies of previous studies that only analyze one uncertainty in isolation.•This method takes the development prospect of LNG promoting project as an uncertain factor for environmental benefit assessment.

Environmental and economic analysis of liquefied natural gas (LNG) for heavy goods vehicles in the UK: A Well-to-Wheel and total cost of ownership evaluation

This paper evaluates the environmental and economic performance of liquefied natural gas (LNG) as a transition fuel to replace diesel in heavy goods vehicles (HGVs). A Well-to-Wheel (WTW) assessment based on real-world HGV drive cycles is performed to determine the life-cycle greenhouse gas (GHG) emissions associated with LNG relative to diesel. The analysis is complemented with a probabilistic approach to determine the total cost of ownership (TCO) across a range of scenarios. The methodologies are validated via a case study of vehicles operating in the UK, using data provided by a large food retailer. The spark-ignited LNG vehicles under study were observed to be 18% less energy efficient than their diesel counterparts, leading to a 7% increase in WTW GHG emissions. However, a reduction of up to 13% is feasible if LNG vehicles reach parity efficiency with diesel. Refuelling at publicly available stations enabled a 7% TCO saving in the nominal case, while development of private infrastructure incurred net costs. The findings of this study highlight that GHG emission reductions from LNG HGVs will only be realised if there are vehicle efficiency improvements, while the financial case for operators is positive only if a publicly accessible refuelling network is available.

Regulated emission characteristics of in-use LNG and diesel semi-trailer towing vehicles under real driving conditions using PEMS

On-road driving emissions of six liquefied natural gas (LNG) and diesel semi-trailer towing vehicles (STTVs) which met China Emission Standard IV and V were tested using Portable Emission Measurement System (PEMS) in northern China. Emission characteristics of these vehicles under real driving conditions were analyzed and proved that on-road emissions of heavy-duty vehicles (HDVs) were underestimated in the past. There were large differences among LNG and diesel vehicles, which also existed between China V vehicles and China IV vehicles. Emission factors showed the highest level under real driving conditions, which probably be caused by frequent acceleration, deceleration, and start-stop. NOx emission factors ranged from 2.855 to 20.939 g/km based on distance-traveled and 6.719–90.557 g/kg based on fuel consumption during whole tests, which were much higher than previous researches on chassis dynamometer. It was inferred from tests that the fuel consumption rate of the test vehicles had a strong correlation with NOx emission, and the exhaust temperature also affected the efficiency of Selected Catalytic Reduction (SCR) after-treatment system, thus changing the NOx emission greatly. THC emission factors of LNG vehicles were 2.012–10.636 g/km, which were much higher than that of diesel vehicles (0.029–0.185 g/km). Unburned CH4 may be an important reason for this phenomenon. Further on-road emission tests, especially CH4 emission test should be carried out in subsequent research. In addition, the Particulate Number (PN) emission factors of diesel vehicles were at a very high level during whole tests, and Diesel Particulate Filter (DPF) should be installed to reduce PN emission.

Study on the Characteristics of Heat Exchanger for Cold Energy Recovery in LNG Vehicles

Abstract LNG (Liquefied Natural Gas) vehicles, which are the transport of disposing of urban pollution, have the advantages of high thermal efficiency and less pollution. Another advantage of LNG vehicles is that the cold energy of the fuel LNG can be recycled for air conditioner. Based on the two fluid model, numerical simulation of the heat transfer characteristics of cold energy recovery heat exchanger in LNG vehicle are carried out. The results can provide a reference for the design of cold energy recovery heat exchanger in LNG vehicle.

КОМПАНИЯ «CRYOSTAR» УКРЕПЛЯЕТ ЛИДИРУЮЩИЕ ПОЗИЦИИ В мировом КРИОГЕННОМ МАШИНОСТРОЕНИИ

Cryogenic reciprocating and centrifugal pumps are widely applied in processes of manufacture, storage, transport and use of cryogenic liquid products, such as oxygen, nitrogen, argon, liquefied natural gas (LNG). Pumps Company «Cryostar» (Ezing, France) characterized by high quality and guaranteed reliability. It is shown how the company is expanding the scope of manufactured pumps created LNG vehicle refueling stations or natural gas, gasified under pressure; constructed in various MEGA-plants; CNG regasification systems; the powerful engines of ships. Promotion of innovative equipment «Sryostar» in Russia and Belarus has been the company «NII KM» (Moscow), which successfully applies it also implemented in their own projects. It reported on the establishment of the company «Сryostar» new test facility with great opportunities to test different types of pumps. This will allow the company to strengthen its leading position in the global cryogenic engineering.

Ethane as a cleaner transportation fuel.

T recent shale gas revolution has increased the supply of ethane to an unprecedented level. The unexpected surplus of ethane has led to exceedingly low prices and a waste of a resource. Currently, the principal use for ethane is ethylene production. The surplus of ethane is turning into an excess of ethylene. The recent collapse of oil prices has greatly lowered the costs of petroleum-based ethylene, and limits the demand for ethane from ethylene producers. A small proportion of ethane may be blended into natural gas, but the heat value specifications limit the amount of ethane allowed. An increasing amount of ethane will likely be flared, which is a controlled burning of the gas only to get rid of it. Some projections suggest that U.S. ethane production may outgrow demand by hundreds of thousands barrels per day in the coming years. Due to the lack of infrastructure to utilize ethane, it is considered a nuisance in shale gas development. The physical and chemical properties of ethane make it a good a transportation fuel. For the same volume, ethane carries slightly more energy than liquefied natural gas (LNG), but is free from the evaporation loss problem in cryogenic LNG systems. The infrastructure required for ethane transportation are similar to those for compressed natural gas (CNG) vehicles, where the same cylinder can carry more than twice amount of energy in ethane than in CNG. A typical welding cylinder designed for CNG with 16.5 MPa pressure rating can hold liquid ethane safely. Even in hot summer days, when the liquid ethane completely evaporates, the pressure will not rise above the pressure rating. The promotion of natural gas vehicles (NGVs) is faced with several challenges. The CNG vehicles have significantly shorter driving ranges per refill than their gasoline or diesel counterparts. The LNG vehicles have similar driving ranges to the conventional vehicles, but require expensive cryogenic supply chain. Ethane vehicles offer longer driving range than LNG vehicles without cryogenic systems. Utilizing ethane to replace natural gas in transportation could potentially lower the market barriers to a clean alternative fuel and accelerate the adoption of gas vehicles in the United States. The end-use carbon intensity of ethane fuel is slightly higher than natural gas, but significantly lower than gasoline and diesel. We were unable to locate any assessments on upstream emissions for ethane. However, because ethane is a byproduct in natural gas production, its upstream emissions should be similar to that of natural gas. Figure 1 shows the well-to-wheel

The Project Design for Cold Energy Recovery of LNG Vehicle Air-Conditioning System

A kind of potential fuel for vehicles is Liquefied Natural Gas (LNG) whose cryogenic energy can be recovered for vehicles air-conditioning system. In this paper, LNG city bus air-conditioning system utilizing LNG cold energy is concerned to be subject investigated. The design requirements of cold energy recovering for LNG city bus air-conditioning system are introduced and the project design is presented.

The development of natural gas as an automotive fuel in China

This manuscript aims to systematically review the development of natural gas as an automotive fuel in China and to draw policy implications for decision making. This manuscript presents a brief overview of natural gas development and the potential of natural gas as an automotive fuel in China, followed by an introduction to the development of various technology pathways for using natural gas as an automotive fuel, including CNG (compressed natural gas) vehicles, LNG (liquefied natural gas) vehicles, and others. This material suggests, a large potential to increase the use of natural gas as an automotive fuel, especially for CNG and LNG vehicles. The following activities will promote the development of natural gas vehicles: prioritizing vehicle use in the utilization of natural gas, supporting the construction of natural gas filling stations, developing a favorable pricing policy for natural gas used in vehicles, and enhancing the research and development to further improve the technology performance, especially for the technology of LNG vehicles.

Towards a Sustainable Urban Freight Transport and Urban Distribution

 Abstract—The objectives of this paper are to: a) develop a comprehensive sustainability impact assessment framework, aiming to improve the use of urban freight transportation in terms of modes, b) support showcasing of urban distribution fleet from a logistics provider and c) apply the proposed sustainability impact assessment framework for the production of outcomes regarding the sustainability performance of urban freight transportation modes. Tools are used such as Life-Cycle Analysis (LCA) for the evaluation of transportation modes, stemming from European Commission transport policy objectives, as well as efficiency and productivity targets, environmental indicators including greenhouse gas (GHG) emissions, etc. In the field of practical showcasing, there will be a case study that will represent its technologies relative to urban distribution fleet. The demonstrator is a Logistics Provider whose main activity is to distribute retail items to an urban area and its interurban agglomeration. The vehicles include two popular light-duty vehicles. As presented below, the score of diesel powered vehicle attains higher sustainability score than the LNG (liquefied natural gas) vehicle thanks to the special characteristics of this type of transportation mode.

Development status of liquefied natural gas industry in China

With the significant economic growth in China, energy related environmental issues become more and more serious. Most of air pollutants are produced by burning coal. In order to achieve a sustainable balance between economic growth and environmental protection, China has been taking measures to expand the role played by natural gas, especially since the beginning of the 21st century. As the liquid form of natural gas, liquefied natural gas (LNG) has also been paid more attention in the country. This paper explores main motives for the fast development of China’s LNG industry. An overview of the industry is also described, covering LNG receiving terminals, plants and transportation. Despite a relatively short development history of LNG industry in China, there are many remarkable successes. City-gas supply by LNG is widely applied in many small to medium cities, and LNG vehicles and cold energy utilization are growing rapidly with governmental supports. At the end, the developmental trends of China’s LNG industry are introduced. All the discussions show that LNG is strategically important in China’s future energy infrastructure.

LNG (liquefied natural gas): A necessary part in China's future energy infrastructure

Abstract This paper presents an overview of the LNG industry in China, covering LNG plants, receiving terminals, transportation, and applications. Small and medium scale LNG plants with different liquefaction processes have already been built or are being built. China's first two LNG receiving terminals have been put into operation in Guangdong and Fujian, another one is being built in Shanghai, and more are being planned. China is now able to manufacture LNG road tanks and containers. The construction of the first two LNG carriers has been completed. LNG satellite stations have been built, and LNG vehicles have been manufactured. LNG related regulations and standards are being established. The prospects of LNG in China are also discussed in this paper. Interesting topics such as small-scale liquefiers, LNG cold energy utilization, coal bed methane liquefaction, LNG plant on board (FPSO – floating production, storage, and off-loading), and LNG price are introduced and analyzed. To meet the increasing demand for natural gas, China needs to build about 10 large LNG receiving terminals, and to import LNG at the level of more than 20 bcm (billion cubic metre) per year by 2020.