Why do fuel vehicles save fuel while electric vehicles consume electricity on highways?

In recent years, new energy vehicles have developed rapidly and have gradually been recognized by the world. Electric vehicles are one of the representatives of new energy vehicles. Many electric vehicle brands such as Tesla, Weilai, and Xiaopeng Motors have emerged. Have you ever thought about why ordinary fuel vehicles save fuel when driving on highways, while electric vehicles consume a lot of electricity when driving on highways? Let's talk about this issue next.

Compared with electric vehicles, the efficiency of the powertrain of fuel vehicles varies greatly with the engine speed. Simply put, the output efficiency of fuel vehicle engines is very low under low-speed conditions, but with the advent of the Atkinson cycle and the Atkinson plus Alto cycle dual-cycle system, as well as the application of turbocharging and direct injection technology, the power output efficiency of the engine under low-speed conditions has been improved.

However, the efficiency of fuel car engines will be greatly improved under high speed conditions. Generally speaking, when the fuel car engine is running at high speed, the power output efficiency can be increased by 30%-45%. The substantial increase in power is far greater than the impact of wind resistance when the vehicle is driving at high speed. In addition, when the car is driving at a high speed and at a constant speed, the number of braking times is relatively small, the power attenuation is relatively reduced, and the power output always maintains efficient output for a long time. Therefore, the fuel consumption of fuel cars when running at high speed is much lower than when running at low speed.

After understanding the changes in the working efficiency of fuel vehicles, let us popularize the changes in the working efficiency of electric vehicles.

First, the working efficiency of electric vehicles is not affected by the speed of the vehicle motor.

The power of electric vehicles comes from the power battery of electric vehicles, so the working efficiency of electric vehicle drive motors is not affected by vehicle speed and motor speed. Generally, the output efficiency of electric vehicle drive motors will be maintained in the range of 80%-90%. The speed of the drive motor changes accordingly with the power supply of the power battery, so the working efficiency of electric vehicles is not affected by the speed of the vehicle motor.

Second, the power transmission process of electric vehicles does not need to go through the gearbox

Unlike fuel vehicles, electric vehicles do not need to pass through a gearbox to transmit power. Therefore, when electric vehicles are driving at low speeds, the power demand is relatively low, and the electric vehicle motor is relatively energy-efficient. However, when electric vehicles are driving at high speeds, the drive motor has a relatively high demand for power because there is no gearbox to assist. Therefore, when electric vehicles are driving at high speeds, the drive motor needs a lot of electricity to maintain the high-speed driving of the car. Therefore, electric vehicles save electricity when driving at low speeds, but consume electricity when driving at high speeds.

Third, the kinetic energy recovery device of electric vehicles can only assist low-speed driving conditions.

When electric vehicles are running at low speeds, especially during frequent deceleration, the reduction in kinetic energy will be converted into battery power and stored in the power battery. When electric vehicles are running at high speeds, the vehicle basically maintains a high-speed and uniform speed, and the kinetic energy recovery device will not work, so this is one of the reasons why electric vehicles consume more electricity when running at high speeds and save electricity when running at low speeds.

Summary: The power output forms of fuel vehicles and electric vehicles are different. When fuel vehicles are driving at low speeds, the power output efficiency is relatively low, but when driving at high speeds, the power output efficiency can be increased by 30%-45%. Therefore, fuel vehicles consume more fuel at low speeds and save fuel at high speeds. Since the power output efficiency of electric vehicles is not limited by the rotational speed and vehicle speed, and they are equipped with kinetic energy recovery devices and lack the assistance of gearboxes, electric vehicles save fuel at low speeds but consume more fuel at high speeds.