How to Calculate Fuel Consumption Correctly?

[HarperMarie]

Fuel consumption per 100 kilometers = Volume of fuel consumed (liters) ÷ Distance traveled (kilometers) × 100. For example: If a car consumes A liters of fuel to travel N kilometers, then the fuel consumption per 100 kilometers = A ÷ N × 100. Of course, the fuel consumption per 100 kilometers is not fixed; factors such as different road conditions, load capacity, temperature, and whether the air conditioning is on all affect fuel consumption. Additional information: Constant-speed fuel consumption refers to the fuel consumption per 100 kilometers obtained by certain types of vehicles in constant-speed fuel consumption tests as stipulated by national standards. These types of vehicles include: 1. M1 category, M2 category with a maximum design total mass not exceeding 3.5 tons, and N1 category compressed natural gas vehicles; M1 category and N1 category vehicles with a maximum design total mass not exceeding 3.5 tons, tested according to the "Test Methods for Fuel Consumption of Passenger Cars." 2. M2 category, M3 category, N2 category, and N3 category compressed natural gas vehicles with a maximum design total mass exceeding 3.5 tons; M2 category, M3 category, and N category vehicles with a maximum total mass greater than or equal to 2 tons, tested according to the "Test Methods for Fuel Consumption of Commercial Vehicles."

[VonZane]

Calculating the correct fuel consumption is actually not difficult. I often use this method when driving: find a gas station and fill up the tank until the pump automatically stops, then note down the current mileage. Drive a certain distance, preferably your daily commuting distance, and then fill up the tank again upon return, recording how many liters of fuel were added this time. Divide the distance traveled by the amount of fuel added and multiply by 100 to get the fuel consumption per 100 kilometers. For example, if you added 15 liters after driving 300 kilometers, the fuel consumption would be 5 liters/100km. Taking multiple measurements and averaging them is more accurate because a single data point can be greatly affected by road conditions. Driving at 80 km/h with a tailwind on the highway can save fuel, but traffic jams in the city or aggressive acceleration can cause fuel consumption to skyrocket, sometimes by more than 2 liters. I calculate it once a month to promptly detect any abnormalities in the car, such as increased fuel consumption due to aging spark plugs. Regular maintenance can also save money and be more environmentally friendly. Learning this method allows you to estimate fuel costs before long trips, making it both practical and useful.

[AlejandroLynn]

To calculate fuel consumption, I empirically recommend this standard method: After filling up the tank, reset the odometer or record the initial mileage. Drive 100 to 500 kilometers, then refill the tank. Divide the amount of fuel added by the kilometers driven and multiply by 100 to get liters per 100 km. The key is to take multiple measurements and average them to eliminate interference factors like cold weather or mountainous roads. I prefer measuring during long-distance driving as it yields more accurate results. Using air conditioning in summer increases fuel consumption by 0.5 to 1 liter, while slow starts in winter also consume more fuel. Using a mobile app to assist with recording is more convenient, such as inputting data to automatically calculate averages. Regularly monitoring fuel consumption can also help optimize driving habits, like maintaining a steady speed which saves 5%-10% on fuel.

[MacEllie]

Accurate Fuel Consumption Calculation: Fill the tank until the pump clicks off and note the mileage. After driving for a few days, refill the tank to full and record the amount of fuel added. Divide the mileage difference by the fuel amount and multiply by 100 to get the fuel consumption. For example, if you add 10 liters and drive 200 km, the consumption is 5 liters/100km. New drivers can try this method—don't worry about inaccuracy at first; you'll get the hang of it with practice.