Fuel Consumption per 100 km

1. Definition and Unit

Fuel consumption per 100 km refers to the volume of fuel consumed by a vehicle to cover a distance of 100 kilometres, measured in litres per 100 kilometres (L/100 km). This metric is the standard industry benchmark for evaluating vehicle fuel economy; a lower reading indicates superior fuel efficiency. For new energy vehicles (NEVs) or hybrid models, fuel consumption per 100 km typically denotes fuel consumption under charge-sustaining conditions (at minimum state of charge).

2. Test Standards and Discrepancies in Figures

Fuel consumption ratings per 100 km vary considerably across different test cycles, primarily due to differing driving profiles and average vehicle speeds.

Test Standard	Average Speed	Characteristics	Typical Tendency
WLTC (Worldwide Harmonised Light Vehicles Test Cycle)	46.5 km/h	Comprises four distinct driving phases (low, medium, high, and extra-high speed) across an 1,800-second cycle; currently the official homologation standard for new vehicles in China	Close to real-world figures
CLTC (China Light-Duty Vehicle Test Cycle)	28.96 km/h	Modelled on actual traffic conditions in China, featuring low, medium, and high-speed phases with a maximum speed of 114 km/h	More favourable for pure electric range; combined fuel consumption ratings are often lower than WLTC
NEDC (New European Driving Cycle)	33.6 km/h	Consists of four urban cycles and one extra-urban cycle; now largely phased out of new car homologation in China	Figures are typically on the optimistic (lower) side

3. Discrepancies with Real-World Fuel Consumption

A variance of 10% to 30% is commonly observed between official laboratory-tested fuel consumption figures and actual real-world driving results, primarily due to the following factors:

Controlled lab settings vs real-world road conditions: Laboratory tests are conducted in wind-free, temperature-controlled environments on flat surfaces, entirely free of traffic lights, congestion, or road gradients.
Driving habits: Aggressive acceleration and harsh braking significantly drive up fuel consumption, whereas smooth, progressive driving yields figures much closer to lab ratings.
Vehicle condition and setup: Test cars are brand-new and run on factory-specified tyre pressures; in daily use, tyre wear, heavier payload, and air-conditioning usage all increase fuel consumption.
Use of auxiliary equipment: Energy-consuming features such as the air-con and heated seats are routinely turned off during homologation tests, but draw extra power and fuel during real-world driving.

4. Practical Tips to Lower Fuel Consumption per 100 km

Maintain an optimal cruising speed: Keep to an economical cruising speed of 60–90 km/h and avoid excessive speeding.
Shed unnecessary weight: Clear out unwanted items and heavy cargo from the boot to reduce kerb weight.
Keep tyres properly inflated: Regularly check and top up tyre pressures to recommended factory levels to avoid higher rolling resistance from under-inflated tyres.
Minimise engine idling: Switch off the engine during extended stops or prolonged waiting periods.
Adopt a smoother driving style: Avoid abrupt throttle inputs, aggressive overtaking, and sudden, hard braking.
Stick to regular service schedules: Replace air filters, spark plugs, and engine oil on time to keep the engine running at peak efficiency.

5. Industry Trends

WLTC and CLTC have superseded NEDC as mainstream homologation cycles, narrowing the gap between official lab ratings and real-world fuel consumption; however, as test parameters remain standardised, discrepancies are inevitable, and buyers should cross-reference figures across multiple operating conditions.
Tightening corporate average fuel consumption standards continue to compel carmakers to lower fleet-wide fuel consumption through hybridisation, lightweight engineering, and next-generation, high-thermal-efficiency engines.
Fuel economy labels for electrified vehicles increasingly incorporate equivalent fuel or electricity consumption conversion values, offering car buyers a clear, standardised benchmark for comparing running costs across petrol, hybrid, and fully electric powertrains.