A month ago, I decided to set myself a challenge to determine how much I could improve fuel mileage by driving more sensibly, and therefore how much money I could save by increasing my mpg.
You’ll be pleased to learn in this article that I follow my own advice. At moneystepper, we suggest anyone with a net worth less than £1m drives a second hand car. This is due to the amount of value that a new car loses as soon as it is driven off the forecourt.
I drive a 2004 Citroen C2 – lovely little car she is!
Because it’s now 10 years old, its mpg isn’t great. However, this doesn’t matter for my experiment. I wanted to determine how much difference I could make to my average mpg by driving sensibly.
My starting point
Now, I’m not a crazy driver my any stretch of the imagination. I usually accelerate fairly slowly, give myself a lot of time to break and don’t go far over the speed limit wherever I am.
My reading on the car over the past several thousand miles showed that my average mpg was 38.7 miles per gallon. This was from a mix of inner city driving, country roads and motorways.
The plan to improve fuel mileage
As per a previous article on moneystepper – How to Improve Your Fuel Efficiency – I already knew how I could improve fuel mileage by driving sensibly. The advice here can be broken down into the following areas:
- Drive in the highest gear possible.
- Avoid high speeds. The optimal speed for fuel efficiency is 55mph. Driving at 85mph uses 25% more fuel than driving at 70mph.
- Don’t accelerate too quickly.
- Avoid heavy breaking.
- Maintain the correct tyre pressure.
- Don’t leave your vehicle idle.
- Remove unnecessary weight from your car.
Therefore, for one month, I decided to live religiously by all of these rules.
Increasing my mpg – the result
After one full month of driving, and over 1,214 miles driven (a few trips over the length of the country for weddings and visiting family brought this number above our usual monthly average), I managed to increase my mpg from the historical average of 38.7 mpg to a much improved 48.2 mpg. This means that I managed to improve fuel mileage by 9.5mpg.
Over the course of the month, 1,214 miles driven at the original 38.7 mpg would have required 31.4 gallons of petrol. This is equal to 142.7 litres of petrol. The latest data from petrolprices.com indicate that the average price of petrol in the UK in October 2014 was 126.7p. Therefore, this petrol under my original driving techniques would have cost me £180.81.
Instead, by driving sensibly, I was able to improve fuel mileage and therefore my petrol use was reduced to 25.2 gallons (114.6 litres) which only cost me £145.19.
Therefore, over the course of one month, I was able to increase my mpg to such an extent that I reduced my petrol spend by £35.61. Annually, that would amount to £427.32.
And the savings wouldn’t end there. Accelerating less quickly would have been better for my engine, less heavy braking would have been better for my brakes, etc etc. Therefore, this more sensible approach to driving would have also led to significant savings in the maintenance of the car.
My only other consideration is whether driving this way detrimentally impacted my life in any way. Well, firstly, I would argue that it is safer and hence my probability of having an accident fell.
The only downside I can think of is time. On the motorway, I tended to drive at around 60 mph during this experiment. One trip we took, according to google maps, was 217 miles one way. At an average of 60mph, this would have taken us 3.6 hours. At an average of 80mph, this could have been reduced to 2.7 hours. Therefore, we could have saved ourselves around 55 minutes by driving more quickly.
However, in that 55 minutes I effectively earned £6.37 (this trip as a proportion of my monthly mileage applied to the monthly savings), it was safer and I didn’t break the law!
Driving sensibly can significantly improve fuel mileage and this can lead to some significant savings. Whilst it may take a little longer to get from A to B, just think about the following benefits:
- You are effectively earning money by driving more sensibly
- You are less likely to be involved in a fatal accident
- Your longer term maintenance costs on your car will also fall
As a final word, I must also highlight that the “maximise your average mpg” game on your electronic display is rather fun!! Safe (and sensible) driving everyone!
Money Beagle says
Gas prices have fallen quite a bit here in the USA. It’s always interesting to see driving habits and how they change for the better when prices go up, but seem to get worse when prices drop. I try to keep a reasonable speed, avoid fast starts and abrupt stops, and other habits regardless of the price. If you only do these things when prices spike, then you’re wasting money otherwise.
Great point. People generally seem more interested in these things when petrol prices are high, but the savings can still be significant even when gas prices are lower.
Joseph Hogue says
Great tips. I think people overlook the safety benefit. Since I started driving the speed limit on the highway instead of the customary 10 mph over that most do, I have not even been close to an accident or had to stomp on the brake abruptly.
A lot of these fall under what some call ‘hyper-miling’
Thanks Joesph. I completely agree – the safety benefits are very often overlooked or at least underestimated.
There is a greater chance of crashing at 80mph than at 70mph, but more importantly, there is a proportionally higher chance of a crash leading to a fatality at 80mph rather than a crash at 70mph.
A 10 year old car already got over 35 mpg? Yowza. I always forget how much better most European cars are compared to American ones.
We just got a 2012 Honda Civic. We mainly drive in-city, which means stop and go. We average around 32-35 mpg. That’s with the Eco mode on. But I’ll definitely try to remember to drive slower and, more importantly, I need to try to accelerate more slowly. (Sounds contradictory!)
This because the measurement for mpg is actually different between US and Europe – crazy huh!
1mpg in the US is around 1.2mpg in Europe. Therefore, 35mpg in Europe would only be around 25mpg in US. This might explain the differences in the fuel mileage!
David Carlson says
Tire pressure is a big one. A few months ago I noticed that my tank was getting low a lot faster than usual. I checked the tires and sure enough one of them was SUPER low. It literally was nearly cutting my mpg in half. Kind of unreal how much of an impact it can have.
Yeah, to get better fuel mileage it is important to drive more sensibly, but car maintenance is also a huge contributing factor!
Paul @ The Frugal Toad says
Planning your route can also lead to better fuel mileage. For instance I often skip one route in favor of taking the access road because there is much less traffic and I can avoid the stop and go traffic.
Good call. One of the major “hypermiling” rules is to plan our your route where there is less traffic, or fewer traffic lights, in order to avoid repetitive braking and accelerating. I didn’t really do that in this experiment, but I bet it would have helped improve my fuel mileage even further.
Joe @ Budget Breakaway says
Nice test! Have always wanted to try this for myself, looks like you have some interesting results! Inspired me to go and pump my tyres up tonight ha!
Join the gang Joe – we’ll start a hypermiling club!! 🙂
I hope that the extra air helps you squeeze a little better fuel mileage out of your car!