Whether you're considering buying an electric, hybrid or internal combustion engine vehicle, you're probably thinking about fuel efficiency. How many mpg does the car get - and is that good? We've calculated the average miles per gallon (mpg) for petrol and diesel and miles per gallon equivalent (MPGe) for hybrid and electric cars to give you a benchmark for understanding how fuel efficient any given car is.
Average Miles Per Gallon
We gathered data from German website Spritmonitor, which enables users to track and calculate fuel efficiency for their personal cars. The resulting database contains over 20 million fuel ups for over half a million vehicles. From this database, we extracted real-life fuel usage data from the past year for petrol, diesel, hybrid and electric cars.
|Fuel Type||Average MPG or MPGe|
Spritmonitor database entries are stored as litres/100km for petrol and diesel cars and kWh/100km for electric cars. For use in the UK, we converted these values into miles per gallon or a miles per gallon equivalent (MPGe) for electric cars. To calculate a MPGe for electric, we calculated how many miles a car can drive on average for £5 worth of electricity (£5 is the approximate cost of a gallon of petrol). We assumed a cost of £1.1/litre for petrol and £0.167/kWh for electricity.
MPGe for Renault Zoe, Nissan Leaf, BMW i3 and Tesla S
The BMW i3 is the most efficient electric car in the UK, achieving 126 MPGe. We also calculated the MPGe for the other all-electric cars specifically available in the UK: Nissan Leaf, Renault Zoe and Tesla S. (We did not include Tesla X due to lack of data points.) You can see the results of our analysis below.
Electric Car MPG