Diesel's descent in popularityAs a result of the diesel scandal, where Volkswagen was discovered to have fitted defeat devices meant to lower emission levels during fuel economy testing, the popularity of the diesel car suffered significantly. By 2021, diesel's share in the UK's new passenger car market had fallen to less than 8.2 percent. This was in direct contrast to steady gains made by electric and hybrid vehicles, with more drivers now choosing battery-fitted vehicles over diesel combustion engines.
There are many types of diesel, most commonly a fractional distillate of petroleum fuel oil, all of which are constantly being developed and adapted for the industry. As of 2006, almost all of the petroleum-based diesel fuels in Europe and North America are an ultra-low sulfur diesel (ULSD). Meanwhile, biodiesel remains a not so widely used choice.