There are various methods for fuel consumption testing, which can be categorized into direct and indirect measurements. The Ministry of Industry and Information Technology (MIIT) uses an indirect measurement method, where light-duty vehicles (with a maximum gross mass not exceeding 3.5 tons) simulate driving on a test bench, operating under specific conditions (such as idling, acceleration, constant speed, deceleration, etc.), measuring the emissions of carbon dioxide, carbon monoxide, and hydrocarbons, and then calculating fuel consumption using the carbon balance method.
The MIIT fuel consumption test adopts the European Driving Cycle method, promulgated in 2000, which designates urban driving conditions and suburban driving conditions as 30% and 70%, respectively. A complete test cycle totals 1180 seconds, including four urban driving sub-cycles and one suburban driving cycle. The maximum speed for urban driving conditions is 50 km/h, lasting 780 seconds; the maximum speed for suburban driving conditions is 120 km/h, lasting 400 seconds.
During the test, vehicles operate under various states such as idling, deceleration, gear shifting, acceleration, and constant speed. Under urban driving conditions, the average speed is only 19 km/h, and idling time is relatively long. Under suburban driving conditions, the average speed exceeds 60 km/h, and constant speed driving time is relatively long. Combined fuel consumption is calculated by dividing the total emissions from both urban and suburban cycles by the total distance covered in these two cycles, and then using the emissions to determine the corresponding fuel consumption value.
Due to numerous uncertain influencing factors in real-world road conditions, the test data is for reference only. Generally, real-world fuel consumption is higher than the tested values.
