Understanding Fuel Efficiency: A Guide To Car Fuel Consumption

Fuel consumption in cars is the amount of fuel used to drive a certain distance. It is measured in gallons per mile (GPM), or litres per 100 kilometres. A lower number indicates more efficient fuel consumption.

Fuel consumption is notated as gallons per mile (GPM) rather than miles per gallon

The window sticker on new US cars displays the vehicle's fuel consumption in US gallons per 100 miles, in addition to the traditional mpg number. A lower number means more efficient, while a higher number means less efficient.

The energy in fuel is required to overcome various losses (wind resistance, tire drag, and others) encountered while propelling the vehicle, and in providing power to vehicle systems such as ignition or air conditioning. Various strategies can be employed to reduce losses at each of the conversions between the chemical energy in the fuel and the kinetic energy of the vehicle.

Different methods are used to approximate the actual performance of the vehicle. The average fuel economy for new 2020 model year cars, light trucks and SUVs in the United States was 25.4 miles per US gallon (9.3 L/100 km). 2019 model year cars (ex. EVs) classified as "midsize" by the US EPA ranged from 12 to 56 mpgUS (20 to 4.2 L/100 km).

Liters per 100 kilometers may be used alongside miles per imperial gallon in the UK. The average consumption across the fleet is not immediately affected by the new vehicle fuel economy: for example, Australia's car fleet average in 2004 was 11.5 L/100 km (20.5 mpgUS), compared with the average new car consumption in the same year of 9.3 L/100 km (25.3 mpgUS).

Fuel economy is a significant factor in air pollution

Fuel consumption is a significant factor in air pollution and many countries impose requirements for fuel economy. The energy in fuel is required to overcome various losses (wind resistance, tire drag, and others) encountered while propelling the vehicle, and in providing power to vehicle systems such as ignition or air conditioning. The average fuel economy for new 2020 model year cars, light trucks and SUVs in the United States was 25.4 miles per US gallon (9.3 L/100 km). The window sticker on new US cars displays the vehicle's fuel consumption in US gallons per 100 miles, in addition to the traditional mpg number. A lower number means more efficient, while a higher number means less efficient. The MIT School of Engineering notes that using MPG to illustrate fuel economy can make small improvements seem outsized. For example, boosting a car's gas mileage from 40 to 60 MPG makes a much smaller impact than boosting an SUV's gas mileage from 10 to 15 MPG, even though the first scenario seems more advantageous at first glance.

Fuel economy is required to overcome losses while propelling the vehicle

The energy in fuel is required to overcome various losses (such as wind resistance, tire drag, and others) encountered while propelling the vehicle, and in providing power to vehicle systems such as ignition or air conditioning.

Wind resistance is the force that opposes the motion of the vehicle. It increases with the square of the vehicle's speed and the square of the vehicle's frontal area. Tire drag is the force that opposes the motion of the vehicle due to the interaction between the tires and the road. It increases with the vehicle's speed and the tires' rolling resistance.

Various strategies can be employed to reduce losses at each of the conversions between the chemical energy in the fuel and the kinetic energy of the vehicle. These strategies include:

• Improving the aerodynamics of the vehicle to reduce wind resistance
• Using tires with lower rolling resistance
• Improving the efficiency of the vehicle's engine
• Using a more efficient fuel

Fuel economy is the amount of fuel used by a vehicle to travel a certain distance. It is typically measured in liters per 100 kilometers or miles per gallon. A lower fuel economy means more fuel is used, while a higher fuel economy means less fuel is used.

Many countries impose requirements for fuel economy due to the significant impact of fuel consumption on air pollution and the importation of motor fuel.

Fuel economy is used to approximate the actual performance of the vehicle

Fuel economy is a metric used to approximate the actual performance of a vehicle. It is notated as gallons per mile (GPM) rather than miles per gallon, so it indicates how many gallons of gas you will use when you drive 100 miles. GPM is the most important metric to review for the purpose of efficiency improvements. The MIT School of Engineering notes that using MPG to illustrate fuel economy can make small improvements seem outsized. For example, boosting a car's gas mileage from 40 to 60 MPG makes a much smaller impact than boosting an SUV's gas mileage from 10 to 15 MPG, even though the first scenario seems more advantageous at first glance.

The energy in fuel is required to overcome various losses (wind resistance, tire drag, and others) encountered while propelling the vehicle, and in providing power to vehicle systems such as ignition or air conditioning. Various strategies can be employed to reduce losses at each of the conversions between the chemical energy in the fuel and the kinetic energy of the vehicle.

Different methods are used to approximate the actual performance of the vehicle. The window sticker on new US cars displays the vehicle's fuel consumption in US gallons per 100 miles, in addition to the traditional mpg number. A lower number means more efficient, while a higher number means less efficient.

Liters per 100 kilometers may be used alongside miles per imperial gallon in the UK. The average fuel economy for new 2020 model year cars, light trucks and SUVs in the United States was 25.4 miles per US gallon (9.3 L/100 km). 2019 model year cars (ex. EVs) classified as "midsize" by the US EPA ranged from 12 to 56 mpgUS (20 to 4.2 L/100 km). The average consumption across the fleet is not immediately affected by the new vehicle fuel economy. For example, Australia's car fleet average in 2004 was 11.5 L/100 km (20.5 mpgUS), compared with the average new car consumption in the same year of 9.3 L/100 km (25.3 mpgUS).

Fuel economy is used to reduce losses at each of the conversions between the chemical energy in the fuel

The average fuel economy for new 2020 model year cars, light trucks and SUVs in the United States was 25.4 miles per US gallon (9.3 L/100 km). 2019 model year cars (ex. EVs) classified as "midsize" by the US EPA ranged from 12 to 56 mpgUS (20 to 4.2 L/100 km).

Liters per 100 kilometers may be used alongside miles per imperial gallon in the UK. The window sticker on new US cars displays the vehicle's fuel consumption in US gallons per 100 miles, in addition to the traditional mpg number. A lower number means more efficient, while a higher number means less efficient.

Fuel consumption is notated as gallons per mile (GPM) rather than miles per gallon, so it indicates how many gallons of gas you will use when you drive 100 miles. These sources note that GPM is the most important metric to review for the purpose of efficiency improvements. The MIT School of Engineering notes that using MPG to illustrate fuel economy can make small improvements seem outsized. For example, boosting a car's gas mileage from 40 to 60 MPG makes a much smaller impact than boosting an SUV's gas mileage from 10 to 15 MPG, even though the first scenario seems more advantageous at first glance.

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