Level 2: The aftermath of exhaust emissions is too troublesome, causing users to feel exhausted

Diesel engines have the advantage of being fuel-efficient, but when it comes to exhaust treatment, it can be a headache for engineers and a concern for car owners. The "three major components" of gasoline engine exhaust - hydrocarbons, nitrogen oxides (NOx), and carbon monoxide - can magically transform into harmless water, carbon dioxide, and nitrogen gas when they come into contact with the famous "three-way catalyst" as a mediator.

Diesel engines are much more complex! It is prone to producing a large amount of difficult to deal with nitrogen oxides (NOx) due to its high air content and low diesel content (oxygen rich combustion) during daily stop and go low load conditions. When it really works hard (under high load), if it accidentally burns diesel incompletely, it will emit black particulate matter (which we often refer to as PM). To deal with NOx, an additional urea injection system (AdBlue for vehicles) is usually required to "neutralize" urea and NOx in the catalyst. To deal with particulate matter, we need to rely on a "particulate filter" (DPF), which acts like a sieve to trap black smoke particles. If they accumulate too much, they need to be specially regenerated and burned. This is equivalent to installing an additional set of "purification equipment" on the car, which not only increases the purchase cost and occupies valuable interior space, but also requires the owner to remember to regularly add urea and worry about the particle trap not getting clogged. Think about it, choosing new energy was originally for the sake of peace of mind and convenience. However, in order to use diesel range extenders, we have to take care of these two "delicate" devices, constantly thinking about adding urea and cleaning particle traps. Isn't this a typical "trouble"? The user experience is greatly discounted, and car companies naturally take a detour.