What Affects Fuel Economy?
Driving style: Aggressive acceleration and braking can reduce MPG by 15-30%. Speed: Fuel consumption increases significantly above 60mph — driving at 70mph uses 9% more fuel than 60mph, and 80mph uses 25% more. Tyre pressure: Under-inflated tyres increase fuel consumption by 3-5%. Weight: Every extra 50kg reduces fuel economy by roughly 1-2%. Air conditioning: Uses 5-10% more fuel. Open windows at low speeds, AC at higher speeds.
How to Improve MPG
Smooth driving: Accelerate gently, anticipate braking, maintain steady speed. Highest gear possible: Higher gears = lower revs = less fuel. Reduce speed: Stick to 60-65mph on motorways. Check tyre pressure monthly: Keep at manufacturer's recommended level. Remove roof boxes/racks when not in use (adds drag). Don't idle: Turn off the engine if stopped for more than a minute. Plan routes: Shorter distance doesn't always mean less fuel — avoid congestion.
Fuel Types
Standard unleaded (E10): Contains 10% ethanol. Suitable for most cars post-2011. Super unleaded (E5): Contains 5% ethanol. 1-2% better fuel economy but costs 10-15p/litre more — rarely worth it unless your car requires it. Premium fuels: Marketing claims aside, premium fuel makes negligible difference in standard cars. Only worth it for high-performance engines that specifically require it.
Realistic MPG
Manufacturer MPG figures are tested in lab conditions. Real-world MPG is typically 10-20% lower. Check real-world figures on Fuelly or HonestJohn before buying.
Related Calculators
Frequently Asked Questions
How can I improve my car's fuel economy?
Drive smoothly (saves 15-30%), maintain tyre pressure (saves 3-5%), stick to 60mph (saves 9% vs 70mph), remove roof boxes, and avoid idling. Combined, these can improve MPG by 20-30%.
Is premium fuel worth the extra cost?
For most standard cars, no. Premium fuel costs 10-15p/litre more but offers negligible improvement. It's only worthwhile if your car specifically requires high-octane fuel (check your manual).