Is 15 litres per 100km good?
In most cases, 15 L/100km is on the high side for a modern petrol car, but the answer depends on what you’re driving and how you drive. For a large SUV or an older vehicle, it can be normal; for a small city car, it’s usually considered inefficient. This article explains what the figure means, when it’s reasonable, and how you can improve it.
What 15 L/100km means
Fuel economy is measured as litres of fuel consumed per 100 kilometres driven. A reading of 15 L/100km means the vehicle uses 15 litres of gasoline to travel 100 kilometres. Lower numbers indicate better efficiency. For context, many modern small cars average around 5–7 L/100km in mixed driving, hybrids often fall in the 3–6 L/100km range, and large petrol SUVs can reach 12–20 L/100km depending on engine size, weight and driving conditions. In terms of emissions, 15 litres per 100 kilometres roughly translates to about 34–35 kilograms of CO2 emitted per 100 km, assuming standard gasoline. Real-world results vary with driving style, terrain, climate control use and vehicle condition.
Is it good? Context matters
Whether 15 L/100km is good depends on the vehicle class and typical usage. Here are common scenarios to consider.
- Small, lightweight petrol cars: 15 L/100km is high compared with typical real-world results (often closer to 5–7 L/100km).
- Mid-size sedans with average engines: 7–9 L/100km is common; 15 L/100km would usually indicate city driving, heavy traffic, or maintenance issues.
- Large SUVs and pickups: 12–20 L/100km is not unusual, especially with frequent stops, hilly terrain, or payloads; 15 L/100km may be typical in real-world use.
- Diesel-powered vehicles: Many diesel engines achieve better efficiency than petrol equivalents, but 15 L/100km can still be high for lighter diesels and expected in heavy-duty use.
- Hybrid and plug-in hybrid models: Often 3–6 L/100km in mixed driving; 15 L/100km would be unusually high unless the vehicle is operating primarily in electric mode or under extreme conditions.
In short, the same number can reflect very different realities. A 15 L/100km reading on a compact city car signals inefficiency, while the same figure on a large SUV in urban congestion may be more understandable.
Real-world vs official ratings
Official fuel economy figures published by manufacturers assume standardized tests and ideal conditions. Real-world results typically run higher or lower depending on your driving style, climate, road grade and accessory use. If your 15 L/100km shows up consistently in everyday driving, it’s worth assessing both vehicle condition and driving habits to determine if improvement is possible.
How to improve fuel economy
If you want to reduce your litres per 100 kilometres, consider these practical steps that apply to most petrol-powered cars.
- Keep tyres inflated to the manufacturer’s recommended pressure and check alignment regularly; under-inflated tyres increase rolling resistance and fuel use.
- Schedule regular maintenance: use the right grade of oil, replace air filters, spark plugs, and dirty fuel injectors as needed to keep the engine running efficiently.
- Drive smoothly: accelerate gradually, anticipate traffic, and use the highest appropriate gear; avoid unnecessary revving and aggressive braking.
- Limit energy waste: minimize unnecessary roof rack use, reduce payload, and use air conditioning judiciously—especially at lower speeds where it can add significant drag and power draw.
- Plan trips to reduce total distance and avoid idle time; combine errands into a single journey when possible.
- Consider a drivetrain upgrade if feasible—smaller, lighter vehicles or modern, more efficient engines (or hybrid options) can yield substantial improvements over time.
Small, consistent changes can yield noticeable fuel savings, particularly if you apply several tips together over time.
Summary
Is 15 L/100km good? The answer is not one-size-fits-all. For a compact modern petrol car, it’s generally high and worth investigating. For large SUVs, older vehicles, or heavy traffic conditions, it may be more common. The key is to compare against your vehicle’s typical performance, official ratings, and real-world driving conditions, then look for targeted improvements in maintenance, driving habits, and weight or aerodynamic improvements where feasible. If you’re shopping for a new car and prioritizing fuel economy, aim for smaller, lighter models or hybrids to achieve lower numbers in everyday use.
Summary of takeaways
- 15 L/100km means about 6.7 km per liter and roughly 345 g/km of CO2 for gasoline-powered cars, on a per-kilometer basis.
- Its desirability is highly context-dependent: common for large vehicles, usually high for small, efficient cars.
- Practical improvements come from maintenance, smarter driving, and reducing unnecessary load or drag.
