New energy vehicles (NEVs), or alternative fuel vehicles, refer to vehicles that use unconventional (non-fossil fuel) energy as a power source (or use conventional vehicle fuels, adopt new vehicle power devices), integrate advanced technologies in vehicle power control and drive, and form vehicles with advanced technical principles, new technologies, and new structures. New energy vehicles include five major types: hybrid electric vehicles (HEVs, mainly divided into oil-electric hybrid vehicles and plug-in hybrid electric vehicles), pure electric vehicles (BEVs) and solar vehicles, fuel cell vehicles (FCEVs), extended-range electric vehicles (REEVs) [1], and other new energy vehicles including mechanical energy (such as supercapacitors, flywheels, compressed air and other high-efficiency energy storage devices) vehicles, etc. Unconventional vehicle fuels refer to fuels other than gasoline and diesel, such as natural gas (NG), liquefied petroleum gas (LPG), ethanol gasoline (EG), methanol, dimethyl ether, and hydrogen fuel [2][3]. In addition, there are some unpopular solutions, such as Stirling engines and six-stroke internal combustion engines, which increase combustion efficiency, and even nuclear energy.
In the early days of vehicle history, there were many solutions that used energy other than gasoline or diesel, or some that could use gasoline or diesel but not internal combustion engines, but these vehicles were eliminated due to their low cost-effectiveness. The revival of this type of vehicle began in the 1970s. The promotion of new energy vehicles was to meet the needs of environmental protection and the oil crisis, and to reduce or abandon the current mainstream models that burn traditional gasoline or diesel to drive internal combustion engines.
In the People's Republic of China, the government stipulates that new energy vehicles include three categories: pure electric vehicles (EV), plug-in hybrid electric vehicles (PHEV), and fuel cell vehicles (FCEV). These three types of vehicles are subsidized in China (expected to be cancelled after 2020) and have convenient travel (for example, in Beijing, pure electric vehicles are not subject to license plate restrictions, etc.). The People's Republic of China expects that new energy vehicles will become the mainstream sales in 2035[4].
The classification of new energy vehicles is roughly as follows. Electric vehicles, internal combustion engine vehicles with alternative fuels, and hybrid vehicles are the mainstream, but some people are developing other solutions:
Because of its simple structure, it is more suitable for cars in the city, but for long-distance driving, it may be necessary to use microwave power during driving. Larger cars can be operated in the way of trolleybuses.
Electricity
Wireless power supply
Battery, the most famous one is Tesla Model 3
Fuel cell, the most famous one is Toyota Mirai
Solar energy
This type of solution is to continue to use internal combustion engines, but switch to other cheaper and less carbon-emitting fuels. In the late 19th century and early 20th century, it also competed with gasoline vehicles. The advantage of being a new energy vehicle is that it is more suitable for heavy vehicles that electric vehicles are not suitable for.
Ethanol, such as the Ford Model T, which originally had an alcohol-fueled version, but was later discontinued because the people who bought this car had low incomes and would only buy the lower-priced gasoline version.
Methanol
Biodiesel
Hydrogen
Compressed Natural Gas (CNG)
Liquefied Petroleum Gas (LPG)
Liquefied Natural Gas
Wood gas was popular before and after World War II, such as Japan's charcoal bus.
Vehicles that use two or more energy sources mainly refer to vehicles that use electric energy to drive electric motors in addition to internal combustion engines. They mainly include:
Hybrid vehicles, which use electric motors to assist internal combustion engines to increase overall energy conversion efficiency. The most famous one is Toyota Prius;
Plug-in hybrid electric vehicles, which mainly use electric motors that can be plugged into the power grid for charging and use internal combustion engines as backup auxiliary vehicles. The most famous ones are Mitsubishi Outlander PHEV and BYD's DM series.
