Types of pure electric vehicles
Since its development, pure electric vehicles have come in many varieties, and are usually classified according to vehicle purpose, number of onboard power sources, and composition of the drive system. Based on different uses, pure electric vehicles can be divided into three types: electric cars, electric trucks, and electric buses.
1. Electric sedans are currently the most common type of pure electric vehicle. Apart from some concept cars, pure electric sedans have already entered small-batch production and entered the automotive market.
2. There are relatively few electric trucks used for power transportation, but in mines, construction sites and some special locations, there are already some large-tonnage pure electric trucks.
3. Electric buses, and pure electric passenger cars are also relatively rare; pure electric buses are used as public buses and have performed well in some city bus routes as well as at the World Expo and world sports events.
Advantages of pure electric vehicles
1. No pollution and low noise: Electric vehicles do not produce exhaust gases like those produced by internal combustion engine vehicles, and therefore do not generate exhaust pollution. This is very beneficial to environmental protection and air cleanliness, and is almost "zero pollution".
As is well known, pollutants such as CO, HC, NOx, particulate matter, and odors in the exhaust of internal combustion engine vehicles contribute to acid rain, acid fog, and photochemical smog. Electric vehicles do not produce the noise of internal combustion engines, and the noise from electric motors is also lower than that of internal combustion engines. Noise can still be harmful to human hearing, the nervous system, cardiovascular system, digestive system, endocrine system, and immune system.
2. Single electric energy source: Compared with hybrid electric vehicles and fuel cell vehicles, pure electric vehicles use electric motors instead of internal combustion engines, resulting in lower noise and no pollution. The space and weight reduction of the electric motor, fuel, and transmission system can compensate for the battery requirements. Furthermore, because it uses a single electric energy source, the electronic control system is much simpler than that of hybrid electric vehicles, reducing costs and also compensating for part of the battery price.
3. Simple structure and easy maintenance: Electric vehicles have a simpler structure than internal combustion engine vehicles, with fewer moving and transmission parts, resulting in less maintenance work. When using an AC induction motor, the motor requires no maintenance, and more importantly, electric vehicles are easy to operate.
4. High energy conversion efficiency: It can simultaneously recover energy during braking and downhill driving, improving energy utilization efficiency;
Studies on electric vehicles have shown that their energy efficiency surpasses that of gasoline-powered vehicles. Electric vehicles are particularly suitable for urban driving, where cars frequently stop and start at low speeds. Electric vehicles do not consume electricity when stopped; during braking, the electric motor automatically converts into a generator, reusing energy generated during deceleration. Some studies indicate that the energy efficiency of crude oil, after refining and sending it to a power plant to generate electricity, which is then used to power batteries and drive a car, is higher than that of crude oil refined into gasoline and then used to power a gasoline engine. Therefore, this method helps save energy and reduce carbon dioxide emissions.
5. Smoothing the peak-valley difference of the power grid: Charging can be carried out at night using cheap "off-peak electricity" from the power grid, which helps to smooth the peak-valley difference of the power grid.
The application of electric vehicles can effectively reduce dependence on oil resources, allowing limited oil reserves to be used for more important purposes. The electricity used to charge batteries can be converted from energy sources such as coal, natural gas, hydropower, nuclear power, solar energy, wind power, and tidal power. Furthermore, charging batteries at night avoids peak electricity demand, which helps balance the grid load and reduces costs.
