Two people can drive the same car on the same road and still use noticeably different amounts of fuel. One leaves the petrol station wondering where all the fuel went, while the other seems to get much more from every litre. The difference isn’t always the car.
How you drive has a real effect on fuel consumption. Rapid acceleration, unnecessary braking, excessive idling and driving at high speeds can all make an engine work harder. And in a city such as Nairobi, where traffic can keep you moving between acceleration and braking for long periods, those habits can add up.
This doesn’t mean you need to drive painfully slowly to save fuel. It is more about driving smoothly and avoiding unnecessary work for the engine.
Hard Acceleration Uses More Fuel
One of the easiest ways to increase fuel consumption is to repeatedly accelerate aggressively. When you press the accelerator hard, the engine has to produce more power, which generally means using more fuel. If you then brake a short distance later because of traffic, much of that energy has effectively been wasted.
This is particularly common in stop-and-go traffic. You accelerate quickly, reach the next vehicle or traffic light, brake, stop and then accelerate again.
A smoother approach is to accelerate progressively and look further ahead. If you can anticipate that traffic is slowing down, easing off the accelerator earlier may allow you to reduce speed without immediately resorting to heavy braking. You won’t eliminate fuel consumption, but you can reduce unnecessary acceleration and braking.
Speed Matters More Than Many Drivers Realise
There is a reason fuel economy figures are often measured under controlled driving conditions. As speed increases, aerodynamic resistance also increases. The engine generally has to work harder to keep the vehicle moving, particularly at higher highway speeds.
This means that driving at 120 km/h can consume considerably more fuel than driving at a moderate cruising speed, even when both journeys cover exactly the same distance.
The difference varies between vehicles because factors such as engine size, gearing, aerodynamics and vehicle weight all matter.
So if you’re trying to stretch a tank of fuel on a long Kenyan highway journey, maintaining a steady, reasonable speed is generally more efficient than repeatedly accelerating to high speeds and then slowing down.
Constant Braking and Accelerating Is Expensive
You cannot control traffic, but you can control how you respond to it. Following too closely often creates unnecessary braking. You slow down when the vehicle ahead slows down, accelerate when it moves, and then brake again when traffic changes.
Looking further ahead gives you more time to respond gradually. This is one reason smooth driving tends to be more fuel-efficient than aggressive driving. You are not constantly converting fuel into motion and then immediately converting that motion into heat through braking.
Nairobi traffic makes this particularly relevant. When congestion is unavoidable, fuel consumption will naturally rise. But unnecessarily aggressive driving can make an already inefficient journey even worse.
Idling Also Uses Fuel
Your car may be stationary, but the engine is still running. Sitting with the engine idling for long periods therefore consumes fuel without moving the vehicle anywhere.
There are legitimate reasons to idle, such as traffic conditions or certain operating requirements. But leaving the engine running unnecessarily while parked or waiting can gradually add to your fuel bill. This is especially worth considering if you regularly spend time waiting in your car.
Air Conditioning Has an Effect Too
Air conditioning requires energy, and that energy ultimately comes from the engine in conventional petrol and diesel vehicles.
The effect varies depending on the vehicle, outside temperature, cooling demand and how the system is being used.
In Kenya, where temperatures can be high, completely avoiding air conditioning isn’t always practical. The sensible approach is to use it when needed rather than treating it as something that must never be switched on.
Also remember that driving with the windows wide open at higher speeds can increase aerodynamic drag, so turning off the air conditioning and opening all the windows isn’t automatically the most efficient solution in every situation.
Short Trips Can Be Surprisingly Inefficient
Driving style isn’t the only factor under your control. Repeatedly taking very short journeys can result in poor fuel economy because the engine and other systems may not spend much time operating under fully warmed-up conditions. You also tend to encounter more starting, stopping and idling relative to the distance travelled.
This is one reason someone who mainly drives short trips around town may see worse fuel economy than another driver covering longer, smoother journeys in the same car. It doesn’t necessarily mean anything is wrong with the vehicle.
Tyres and Maintenance Still Matter
You can drive perfectly smoothly and still get poor fuel economy if the car itself isn’t in good condition. Incorrect tyre pressure can increase rolling resistance. Poor wheel alignment can cause unnecessary tyre drag and uneven wear.
A dirty or restricted air filter on vehicles where it affects airflow, mechanical problems and overdue maintenance can also contribute to higher consumption. This is why fuel economy should not be blamed entirely on the driver.
If your fuel consumption has suddenly become much worse, rather than gradually changing because of your driving habits, the car itself deserves attention.
So How Much Can Driving Style Actually Change?
There isn’t one percentage that applies to every driver or every car. The difference depends on the vehicle, road, traffic, weather, driving speed and how dramatically the driver’s habits change.
But the principle is clear: aggressive acceleration, high speeds, unnecessary idling and repeated hard braking can increase fuel consumption, while smoother acceleration, anticipation of traffic and steady cruising can help reduce it.
The biggest gains usually come from changing repeated habits rather than searching for one magic fuel-saving trick. And there is another benefit. Smooth driving generally puts less stress on components such as the brakes and tyres as well.
There yu have it, your driving style doesn’t magically turn a fuel-hungry car into an economical one, but it can make a meaningful difference to how much fuel that car uses. If you’re constantly accelerating hard, braking heavily, driving at unnecessarily high speeds and leaving the engine idling, you’re likely spending more at the pump than you need to.
The good news is that unlike the price of fuel or the engine fitted to your car, your driving style is something you can change immediately.
You don’t have to drive like you’re trying to win a fuel-economy competition. Just accelerate smoothly, look ahead, avoid unnecessary speed and give the car a chance to keep moving rather than repeatedly making it speed up and slow down. Sometimes, saving fuel starts with simply changing the way you drive.