ConfusedAboutEnergy.co.uk

Calculate your real MPG and take part in our Real MPG Survey

It’s hardly surprising that car manufacturer’s official MPG figures do not give an accurate indication of real fuel economy performance. The figures are obtained by technicians gently driving cars on a rolling road in a lovely warm laboratory. We believe there is an alternative. Real drivers collect and share their real MPG figures from driving on real roads in the real British weather!

How reliable are official MPG figures?

Have you ever checked your real MPG with the figures quoted by car manufacturers in their glossy brochures? If you have, then you probably got quite a shock. Real MPG figures can vary quite significantly from the official figures, but why? It’s because the tests used to obtain the figures are not representative of real life driving.

Korean and American Super Minis outstrip the Europeans on fuel Efficiency

The ‘Super Mini’ is one of the most popular types of car in the UK; it includes cars such as the Ford Fiesta, Renault Clio, and Volswagen Polo. So we thought it would be an interesting exercise to compare the fuel economy of cars in this category. It proved to be quite a time consuming and difficult task, but the results were very surprising.

With the current high fuel prices, even a relatively small improvement in your MPG can save you money. Most drivers will be able to make savings by changing their driving habits and techniques.

For the average human body weight of 65kg, (Average female is 60kg average male is 70kg) a 1 km walk at say 6 km/hour burns about 50kcal of energy (kcal or kilo-calories are often confusingly shortened to just Calories). The 50kcal came from digestible foods, or the digestible chemical energy in the foods. 50kcal converts to approximately 0.06 kWh of energy.

Petrol vs Diesel – Which is cheaper to run?

In recent years the popularity of diesel engines has steadily increased to the point where sales of diesel cars now slightly exceed those of petrol cars.

The introduction of turbo diesels and fuel injection technology has significantly improved the performance of diesel engines. In addition, you typically get more MPG from a diesel (and therefore less CO2 emissions) and with rapidly increasing fuel costs and the introduction of a CO2 based taxation system, diesels are also now considered cheaper to run.

Many consider that electric cars produce no CO₂. Well in operation this is true they do not, however when they are charged they take electrical energy from the electrical power grid which has in turn been generated by 80% fossil fuels.  The upshot is that using an electric car will also produce CO₂, but according to the calculations below it is about half that of a car powered by internal combustion and in the UK it could cost 3 times less than petrol!  This is great, but the technology infrastructure for electric cars is still some time off, so don’t run off the car showroom yet!