What are the differences between China 6 and China 5 emission standards?
2 Answers
The differences between China 5 and China 6 emission standards are as follows: Different emission standards: China 6 emission standards are more than 30% stricter than China 5. Excluding the influence of working conditions and testing, gasoline vehicles' carbon monoxide emissions are reduced by 50%, total hydrocarbons and non-methane hydrocarbons emissions are reduced by 50%, and nitrogen oxide emissions are reduced by 42%. Different implementation times: The China 5 standard was implemented nationwide on January 1, 2017. China 6 has been implemented since July 1, 2019. Different principles: During the China 5 phase, diesel and gasoline vehicles had different emission standards, but China 6 adopts a fuel-neutral principle, meaning the emission limits are the same regardless of the fuel type. Different issuing departments: The China 5 standard was issued by the Ministry of Environmental Protection. The China 6 standard was issued by the Ministry of Environmental Protection and the General Administration of Quality Supervision, Inspection, and Quarantine. Different letter representations: China 5 is represented by 'V', while China 6 is represented by 'VI'. Different monitoring requirements for plug-in hybrid electric vehicles: Compared to China 5, China 6 has improved monitoring requirements for plug-in hybrid electric vehicles, including energy storage systems, thermal management systems, brake regeneration, drive motors, generators, and other regulations. China 5 standard limits are as follows: Gasoline vehicles must not emit more than 1000 milligrams of carbon monoxide per kilometer driven. Gasoline vehicles must not emit more than 68 milligrams of non-methane hydrocarbons per kilometer driven. Gasoline vehicles must not emit more than 60 milligrams of nitrogen oxides per kilometer driven. Gasoline vehicles must not emit more than 4.5 milligrams of PM fine particles per kilometer driven. China 6 has two standards: China 6a and China 6b, as follows: China 6a standard limits: Gasoline vehicles must not emit more than 700 milligrams of carbon monoxide per kilometer driven. Gasoline vehicles must not emit more than 68 milligrams of non-methane hydrocarbons per kilometer driven. Gasoline vehicles must not emit more than 60 milligrams of nitrogen oxides per kilometer driven. Gasoline vehicles must not emit more than 4.5 milligrams of PM fine particles per kilometer driven. China 6b standard limits: Gasoline vehicles must not emit more than 500 milligrams of carbon monoxide per kilometer driven. Gasoline vehicles must not emit more than 35 milligrams of non-methane hydrocarbons per kilometer driven. Gasoline vehicles must not emit more than 35 milligrams of nitrogen oxides per kilometer driven. Gasoline vehicles must not emit more than 3 milligrams of PM fine particles per kilometer driven. Affected by the China 6 emission policy, although China 5 vehicles are not currently restricted in normal use, their resale value will be significantly impacted. For truck owners, if they purchase a truck on loan for cargo transport, the depreciation of the vehicle after repaying the loan is equivalent to the net profit during that period. A higher residual value means more profit for the owner. Therefore, from this perspective, China 6 vehicles, which have a longer service life and more road rights, are more advantageous.
China's Stage 6 emission standards are significantly stricter than Stage 5, imposing higher requirements on vehicle pollution control. Specifically, Stage 5 set the nitrogen oxides (NOx) limit at about 60 milligrams per kilometer, while Stage 6a reduces it to 35 milligrams, and Stage 6b tightens it further to around 20 milligrams. Stage 6 also introduces Real Driving Emissions (RDE) testing, which simulates real-road conditions to check emissions, unlike Stage 5 that only conducted lab tests. Technologically, Stage 6-compliant vehicles must be equipped with better Diesel Particulate Filters (DPF) to handle fine dust, and some diesel models use Selective Catalytic Reduction (SCR) systems to reduce NOx. This leads to increased manufacturing costs, potentially raising new car prices by 10,000 to 20,000 yuan, but in the long run, it's more environmentally friendly, helping reduce smog and health risks. However, Stage 6 vehicles may have slightly higher fuel consumption, and during maintenance, it's important to use low-ash engine oil to avoid DPF clogging. I strongly support this upgrade as it helps make the air cleaner.
