How is the 100-kilometer fuel consumption of a car calculated?
2 Answers
The calculation formula for 100-kilometer fuel consumption is: 100-kilometer fuel consumption = fuel refill amount / (kilometers driven after refill * 100). 100-kilometer fuel consumption refers to the fuel consumption of a vehicle traveling 100 kilometers on the road at a certain speed. It is a theoretical indicator of the vehicle. For example, the Xingyue L has different 100-kilometer fuel consumption for different models: Xingyue L-2021 model-2.0TD-DCT-EVO two-wheel drive Luxury, Flagship, Premium, and Intelligent Premium versions (5 models in total) have a fuel tank capacity of 55L. A full tank can run for 808km, and the 100-kilometer fuel consumption is 55/808*100=6.8L. Xingyue L-2021 model-2.0TD high-power automatic four-wheel drive Flagship and Premium versions (2 models in total) have a fuel tank capacity of 62L. A full tank can run for 795km, and the 100-kilometer fuel consumption is 62/795*100=7.8L. The 100-kilometer fuel consumption is a value measured by the manufacturer in an objective environment using a dynamometer installed on the vehicle's chassis, converted into speed parameters, and then calculated under specified speeds to obtain the theoretical experimental 100-kilometer fuel consumption data for the model. The level of a car's fuel consumption is directly related to five major factors: driving habits, the car itself, road conditions, natural wind, and environmental temperature. Specific factors that increase fuel consumption are as follows: Driving habits: Aggressive driving, such as long-term high-idle low-speed driving, sudden acceleration, frequent overtaking, and not releasing the throttle in advance when encountering a red light, will increase fuel consumption. The car itself: Cars with larger displacements consume more fuel than those with smaller displacements because larger displacements generally mean higher power, requiring more gasoline to burn for work. Cars with greater self-weight consume more fuel because greater weight requires more driving torque. For example, SUV models consume more fuel than sedan models. Road conditions: Dirt roads, muddy roads, soft surfaces, mountain roads, etc. Driving on these surfaces increases resistance and fuel consumption. Natural wind: Driving against the wind or on windy days, opening windows at high speeds increases wind resistance, thereby increasing the car's resistance and fuel consumption. Low environmental temperature: When the engine block temperature is low, the gasoline injected during a cold start is not easy to atomize, requiring more gasoline to be injected for combustion, thus increasing fuel consumption. At the same time, the engine computer will control the use of higher RPMs to warm up the car in low temperatures, which also increases fuel consumption.
I've been driving for ten years, and calculating actual fuel consumption is quite simple. Every time I refuel, I fill up until the pump automatically stops, and then reset the trip meter on the dashboard. After driving 300-400 kilometers, I refill the tank and note how many liters were added. For example, if I added 36 liters after driving 450 kilometers, dividing 36 by 4.5 (per 100 kilometers) gives 8 liters per 100 kilometers. This method is much more accurate than the car's onboard computer. It's important to avoid testing during heavy traffic or after aggressive driving on short trips; the best conditions are regular commuting routes. I've noticed that my fuel consumption drops by over 1 liter when I drive on the highway weekly, but it increases when using air conditioning or carrying a full load in the summer.
