What is Fuel Economy?

By CarMoney August 26, 2021
What is Fuel Economy?

When it comes to getting a new car, fuel economy is probably one of the most important aspects! But what does all the jargon mean? We’ve put together this guide to answer all your fuel related questions from MPG to national averages. Car finance isn’t cheap, so make sure your car isn’t guzzling fuel!

In a nutshell, your car’s economy is how far it can travel on a certain amount of fuel. This can be affected by a number of factors from your style of driving, whether you do more motorway or town driving and what kind of fuel your car uses. 

What is MPG and How is it Calculated?

Miles per gallon (or MPG) refers to how far your car is able to travel for every gallon (or 4.55 litres) of fuel it uses. If you have a car that can manage 45MPG and you put a single gallon of fuel in it, you should be able to drive 45 miles before running out! Although, miles per gallon is not used unanimously around the world. Some countries use l/100km.

You will notice that a car’s MPG fluctuates depending on the situation. To make up for this, the WLTP tests (Worldwide Harmonised Light Vehicle Test) have multiple phases:

  1. Low – Simulates driving in a city
  2. Medium – Simulates driving in a town
  3. High speed – Simulates driving on rural roads
  4. Extra high – Simulates driving on motorways
  5. Combined – As you probably guessed, all of the above are put together!

Manufacturers will usually push the combined MPG when selling a car, as this gives the best overall view of the car’s economy. Additionally, keep in mind that imperial, or British gallons are different from U.S. gallons. Specifically, a gallon in the UK is slightly larger, constituting 4.55 litres as compared to 3.79 litres in the U.S.

How is a Car’s Economy Calculated?

A car gets its MPG statistics from the WLTP tests that are done by an independent body. It tests each parameter of driving and gives an overall average, which is the number you will see on the adverts/in dealerships. It is essentially a series of standardised tests that see how efficient a new car really is. Car models must be WLTP certified before they go on sale in the UK, which also helps car buyers see how fuel economy figures compare between different cars.

This is because the WLTP tests also factor in the effects that optional equipment and higher-spec trim levels can have on a car’s fuel consumption. For example, fuel economy will likely get worse if you fit larger than normal wheels onto your car, as they will be heavier and likely less aerodynamic. Other factors such as weather, tyre tread, style of driving, number of occupants/weight in the car will all also have a drastic effect on your fuel economy. 

What is a Good Number of Miles per Gallon?

It is hard to say with certainty as every car is different, so a different level of fuel efficiency could be considered good in one car and not in another. But if you are looking for real good fuel economy, anything over 45/50MPG is considered very good!

While the WLTP tests have been designed to be just like real-world driving, they are still done in a lab. As a result, you may struggle to match your car’s quoted MPG figures behind the wheel. It is a safe bet to use MPG stats as a comparison for different cars. You shouldn’t take it as a guarantee of the car’s economy. 

How can I Improve my Fuel Economy?

Photo by Suzy Hazelwood from Pexels

If you find yourself burning fuel faster than you would like to be, perhaps take a look at one of the following potential causes:

  1. Engines burn more fuel at high revs, so change up sooner
  2. The tyres you have on are worn/low on air
  3. Avoid hard acceleration and braking if possible
  4. Any aftermarket additions could add to the car’s aerodynamic drag

Underinflated tyres are a big cause of problems, as you sometimes don’t notice right away or sometimes not at all. So it is important to constantly be checking your tyre’s tread and pressure.

Cars with Great MPG Stats:

The top 3 most efficient cars on the market are as follows:

1. Suzuki Celerio: 57.8MPG

2. Suzuki Ignis 1.2 Hybrid: 59.9MPG

3. Toyota Yaris 1.5 Hybrid: 59.93MPG

If none of them look too appealing, then why not have a look at the cars on our website and filter to the more economical models with our search function! Or why not see if you could be accepted with our soft-search car finance calculator? Our expert panel of lenders will give a quick decision and you could be driving in no time at all! 

CarMoney LIMITED is authorised and regulated by the Financial Conduct Authority (FCA) for consumer credit activity and our registration number is 674094. Representative 17.9% APR. Over 18’s only. CarMoney IS A BROKER NOT A LENDER.

REGISTERED ADDRESS: Pioneer House, 2 Renshaw PL, Motherwell, ML1 4UF, Scotland.Company Number: SC467274.

All finance is subject to status and income. Written Quotation on request. CarMoney Limited can introduce you to a limited number of finance providers based on your credit rating and we will receive a commission for such introductions.