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In the past two years, using the development of LPG vehicles as a solution to the problem of vehicle exhaust pollution affecting urban air quality has become a hot topic in major cities. So, since everyone agrees that the development of LPG vehicles is a good thing for **, society, and indeed for each of us individualmente, and since authorities at all levels have provided support for this initiative to varying degrees, why then has there been no significant progress in the development of LPG vehicles in major cities to date? Regarding this, I would like to share my humble opinions by drawing on the development trends in some cities in China as well as the experiments and tests conducted by our company over the past year or so. I. To accelerate the development of gas-powered vehicles, it is necessary to ensure a convenient supply of fuel for such vehicles. The supply of vehicle fuel must be as convenient as refueling a car. Using “gas stations” to supply gaseous fuel to gas-powered vehicles is a practice widely adopted around the world today; it represents the simplest and most advanced method for supplying fuel to such vehicles, and this fact is recognized by everyone. However, the construction of gas stations is subject to restrictions related to fire safety distances as well as the overall urban development plans. Given the current state of urban development in China’s major cities, it is extremely difficult to establish even a sufficient number of gas stations that are properly located to meet the fueling needs of gas-powered vehicles, let alone adding eight more temporarily. The construction of CNG stations fails to form a network, and it does not address the issue of convenient gas supply for fuel cell vehicles; this has become the main obstacle preventing the development of such vehicles in various cities. To address issues such as the construction of gas stations, **the relevant authorities are currently formulating design and construction standards for vehicle liquefied petroleum gas filling stations. In my opinion, although in order to promote the development of gas-powered vehicles, **the new design and construction standards for gas stations will relax the safety distance requirements for their construction, taking safety into account, it is not possible to resolve all the issues associated with building gas stations. This is because: 1. Liquefied petroleum gas is after all a flammable and explosive hazardous material, so its storage and filling must adhere to certain safety distances as well as various regulatory requirements. 2. The urban redevelopment in major cities has been largely completed, and it is quite difficult to build additional facilities such as gas stations on the existing infrastructure in those cities. Therefore, even after design and construction standards for gas stations are established, it will still take a very long time to improve the construction of such stations and to create a rational network layout. In the face of this situation, there are two options available: one is to wait for the guidelines for the design and construction of CNG stations to be established, and then gradually improve and build such stations one by one, while also implementing modifications to the fuel systems of existing vehicles in a phased manner. Based on 15,000 taxis and buses in Changchun, at least 30 such CNG stations are needed. It will take approximately 10 years to build these stations and modify the existing vehicles to use CNG. Another option is to temporarily move away from the advanced method of gas supply at filling stations; that is, while gradually improving the construction of such stations, use a bottle-changing system for gas supply as a temporary solution to the issues related to the distribution of filling stations and insufficient gas supply. Once a proper gas supply network is in place, then switch back to using filling stations for gas supply. The key issue here is to properly design the tooling for bottle replacement. That is, the fixation of vehicle gas cylinders in the vehicle and the sealing of the cylinder valves must meet the **fixation strength and sealing requirements specified by the installation standards.** Ensure safe use, enable quick and simple cylinder replacement, and at the same time meet the requirements of gas filling operations. To solve the above problems. I have been organizing research with relevant engineering and technical personnel since October 1997. With the cooperation of units such as Harbin Jiancheng Machinery Factory, we have successively developed detachable cylinder mounting brackets and quick-connect valves for Santana and Jetta taxis as well as large public buses. These mounting brackets and quick-connect valves have undergone multiple improvements and tests for strength and sealing performance; furthermore, they have been tested in actual use on prototype taxis and public buses for nearly a year. Their ability to secure cylinders firmly and ensure good sealing meets all the requirements specified in the industry standards set by the former Ministry of Machinery regarding \"Special Devices and Installation Requirements for LPG Vehicles.\" The simplicity of replacing cylinders and performing gas-related operations also meets the design objectives set forth. At present, this set of tooling has been entrusted to the **Automobile Quality Supervision and Inspection Center** to carry out inspections in accordance with the standards of the **automobile industry** ； In accordance with the requirements of the draft regulations for the type approval tests of LPG vehicles, further reliability tests must be conducted; only after these tests are successful can the vehicles be officially installed and put into use. I believe that although this replaceable gas supply method is bulky and outdated (it is actually quite simple to use), in the current situation where a network of gas filling stations has not yet been established, using it as an auxiliary gas supply method during the initial stage of the development of vehicle fuel cells can not only promote the advancement of fuel cell vehicles by freeing their development from the constraints imposed by the lack of gas filling stations, but it also helps to accelerate the construction of such stations. Therefore, under the current conditions, this replaceable gas supply method represents a viable solution for accelerating the development of fuel cell vehicles and addressing the issue of convenient gas supply. II. To accelerate the development of gas-powered vehicles, it is necessary to reduce the cost of fuel for such vehicles, so that their operating costs are significantly lower than those of vehicles powered by gasoline, thereby increasing the appeal of using gas-powered vehicles. At present, another significant issue affecting the development and use of gas-powered vehicles is the price and cost of vehicle fuel. Due to resource constraints, some cities in the south are forced to use imported liquefied petroleum gas as a fuel source for vehicles. Although imported liquefied petroleum gas has relatively stable quality and its composition can be adjusted to meet the specific quality requirements for vehicle fuel, its price is high; sometimes it is even close to the price of gasoline ； In some cities in the north, although there is an abundance of liquefied petroleum gas resources, there is no liquefied petroleum gas available that fully meets the quality standards required for use in vehicles, as the domestically produced gas does not satisfy these standards ； In some cities, due to restrictions on the types of vehicle fuel that can be used, they are forced to use imported gas or pure propane, and the price of these fuels is roughly on par with that of gasoline. This price does not offer a significant advantage over gasoline, which therefore hinders the use and development of fuel-cell vehicles. Changing automobile fuel from gasoline to natural gas or liquefied petroleum gas can truly be considered a revolution. For many years, people have been accustomed to using gasoline; now, switching to gas requires not only a change in mindset but also an additional cost for the modifications needed. Therefore, unless gas offers a significant price advantage over gasoline, it is difficult to implement such a change, even with mandatory orders. To solve this problem, two aspects of work must be done. First, **preferential policies should be granted for the development and use of liquefied petroleum gas in vehicles, and the prices of such gas for use in vehicles (both purchase price and wholesale price) should be protected.** This gives LPG for vehicles a clear advantage over gasoline. Secondly, in terms of the selection of liquefied petroleum gas for use in vehicles, it is necessary to base it on ordinary domestic civilian-grade gas; while strictly controlling the sulfur and butadiene content in the existing civilian liquefied petroleum gas, large amounts of this ordinary civilian-grade liquefied petroleum gas should be used. To address this issue, we have carried out two sets of tasks since the trials began last October. First, based on the liquefied petroleum gas production and supply capabilities of oil refineries belonging to various ethnic groups in the Northeast region, the refineries under the Daqing Petroleum Administration were selected as future supply bases for vehicle fuel. The Daqing Petroleum Administration was approached on multiple occasions regarding the standards for vehicle fuel, with requests that it reduce the levels of sulfur and butadiene in the existing liquefied petroleum gas intended for domestic use. Now, the Daqing Petroleum Administration has accepted our request and is working on a plan for improvements. Secondly, during the testing process, a mixed civilian gas with low levels of sulfur and butadiene, and values close to the **standard, was selected; vehicle-mounted equipment was adjusted accordingly for use in these tests. To date, we have used the selected equipment and gas to conduct continuous tests on bus vehicles and taxi cars for over two months, with good results. After further operation for a period of time, the engines of the test vehicles as well as the liquefied petroleum gas equipment mounted on them will be inspected in detail. If no issues are found, they can then be approved for widespread use. I believe that in our Northeast region, due to the abundant availability of oil and liquefied petroleum gas resources, especially household-use liquefied petroleum gas, whose supply far exceeds societal demand and whose price is relatively low, vehicle fuel should be based on ordinary household gas in order to facilitate the development of gas-powered vehicles. III. To accelerate the development of gas-powered vehicles, it is necessary to select, adjust, and improve the vehicle-related equipment based on the specific characteristics and requirements of gas-powered vehicle use in the local area. Due to differences in usage conditions such as local temperatures, the quality of liquefied petroleum gas, vehicle types, and vehicle condition, the technical specifications of equipment designed for use with liquefied petroleum gas in vehicles must be carefully selected, tested, and adjusted. Only in this way can the technical feasibility for the development of gas-powered vehicles be made a reality. Given the specific conditions in Changchun, such as low winter temperatures and poor condition of public transportation vehicles, we have set the following three goals for the selection, improvement, and testing of vehicle equipment. 1. The vehicle appliances selected must be suitable for use with liquefied petroleum gas containing the civil mixture specified. 2. They should have good and simple starting performance in cold weather when liquefied petroleum gas is difficult to vaporize. 3. Since the bus engine is located alongside the passengers, the appliances chosen, especially the mixer kits installed on the carburetor, must have sealing mechanisms to prevent the liquefied petroleum gas remaining in the hoses between the pressure-reducing evaporator and the mixer from leaking out after the vehicle stops, thereby avoiding an odor of liquefied petroleum gas inside the vehicle. During the design process of LPG filling stations, we encountered several issues in these areas that we would like to discuss with our colleagues present here. First and foremost, the main issue at hand is the fire safety spacing requirements. Building CNG stations in urban areas where every inch of land is valuable makes it impossible to meet the spacing requirements stipulated by the current \"Code for Design of Urban Gas Systems\" and \"Code for Fire Protection of Buildings\". Furthermore, in order to make full use of the existing conditions, expanding CNG filling stations at liquefied gas bottling plants and bus company gas stations also raises issues related to fire safety distances. Therefore, we place high hopes on the new design standards for CNG filling stations, hoping that these new standards will be able to accommodate various situations. Secondly, there is the issue of the burial depth of underground liquefied gas storage tanks. In the Changchun area, the depth of permafrost in winter can reach up to 1.7 meters. If the tanks are buried below the freezing line of the soil, the depth at the bottom of the tanks will be at least 3.4 meters. This inevitably results in the tanks being submerged in water during summer, which accelerates corrosion. Additionally, cavitation is likely to occur when operating the liquefied gas pumps. Thirdly, there is the issue of equipment selection. The main equipment used in gas filling stations, such as gas filling machines, is imported from abroad, and the temperature range for which the accompanying instruments can function properly is rarely sufficient to go down to -30°C. Moreover, the automatic control systems required for gas filling stations have high standards; interlock controls between pumps and gas filling machines are necessary, and the liquid level in underground storage tanks should not have too large a blind zone. There is a need for both on-site indication and remote control, as well as automatic alarm functions for upper and lower limits. Therefore, careful consideration and research are needed when selecting such equipment. Fourthly, in terms of the design of gas filling stations, we have considered both the more conventional type of station that can be built when there is sufficient funding and space, and we have also drawn on foreign standards to design mobile stations and stations using cylinder sets. More recently, we have developed gas filling stations equipped with movable storage tanks, allowing for flexible approaches depending on the specific conditions of each location. This has laid the foundation for the development of liquefied gas vehicles in the early stages. In summary, in the process of designing gas filling stations, it is necessary for the relevant industry authorities to establish practical guidelines to regulate related activities; at the same time, flexible measures must be adopted based on local conditions while ensuring safety, so that experience can be accumulated over time to improve the construction of such stations. After nearly a year of selection, improvement, and testing, the aforementioned testing objectives we set have been largely achieved. I believe that although there is a wide variety of liquefied petroleum gas appliances for use in vehicles produced by various countries today, and the technology behind them is quite mature, there is still a need to adjust, improve, and adapt these appliances to the specific local conditions of use. Not all advanced foreign technologies, equipment, and experiences are applicable to the various conditions in different regions of our country; (it’s impossible for them to be applicable to all cases). Nor are those foreign technologies, equipment, and experiences that are not applicable to our specific circumstances less advanced – there is indeed an issue related to differences in usage conditions. This requires us to conduct research, absorb and understand the relevant knowledge, and conduct experiments. It is absolutely impossible to simply copy foreign experiences; only in this way can we find a path suitable for China’s national conditions to accelerate the development of gas-powered vehicles. Due to our limited capabilities, our testing and experimentation have not yet been fully completed. Therefore, the views expressed here are not necessarily correct, and I welcome feedback and criticism from my colleagues.